sv1-sv2 routing

.env.example

@@ -15,10 +15,21 @@ BITCOIN_RPC_TIMEOUT=10000
 # BITCOIN_ZMQ_HOST="tcp://192.168.1.100:3000"
 
 API_PORT=3334
+
+# Plain TCP Stratum ports accept both SV1 JSON-RPC and SV2 Noise/binary traffic.
 STRATUM_PORTS=3333,3332,3331,3330
 
+# Optional additional SV2-only mining ports. Usually unnecessary when STRATUM_PORTS are exposed.
+#STRATUM_V2_PORTS=
+#SV2_START_DIFFICULTY=100000
+#SV2_TARGET_SHARES_PER_MINUTE=2
+#SV2_DIFFICULTY_CHECK_INTERVAL_MS=60000
+#SV2_AUTHORITY_PRIVKEY=
+
 STRATUM_SECURE=true
 SECURE_STRATUM_PORTS=4333,4332,4331,4330
+STRATUM_MAX_CONNECTIONS_PER_LISTENER=10000
+STRATUM_TLS_HANDSHAKE_TIMEOUT_MS=10000
 
 #optional telegram bot
 #TELEGRAM_BOT_TOKEN=

.npmrc

@@ -0,0 +1 @@
+omit=optional

Dockerfile

@@ -2,7 +2,7 @@
 # Docker build environment #
 ############################
 
-FROM node:18.16.1-bookworm-slim AS build
+FROM node:24.16.0-bookworm-slim AS build
 
 # Upgrade all packages and install dependencies
 RUN apt-get update \
@@ -24,7 +24,7 @@ RUN npm i && npm run build
 # Docker final environment #
 ############################
 
-FROM node:18.16.1-bookworm-slim
+FROM node:24.16.0-bookworm-slim
 
 # Expose ports for Stratum and Bitcoin RPC
 EXPOSE 3333 3334 8332

README.md

@@ -45,6 +45,20 @@ Install pm2 (https://pm2.keymetrics.io/)
 $ pm2 start dist/main.js
 ```
 
+When running the worker app in PM2 cluster mode, start the PM2 daemon with OS-level
+connection scheduling. The environment variable must be present when the PM2 daemon
+starts, not only in the worker configuration.
+
+```bash
+$ NODE_CLUSTER_SCHED_POLICY=none pm2 start ecosystem.config.js
+```
+
+Cluster-mode connection dropping requires Node.js `22.12.0` or newer.
+
+`STRATUM_MAX_CONNECTIONS_PER_LISTENER` is enforced per worker and Stratum port.
+Size it using the busiest port: `worker count * limit`. For example, 28 workers
+with the default limit of `10000` allow up to `280000` connections on one port.
+
 ## Docker
 
 Build container:

package.json

@@ -5,6 +5,9 @@
   "author": "",
   "private": true,
   "license": "UNLICENSED",
+  "engines": {
+    "node": ">=22.12.0"
+  },
   "scripts": {
     "build": "nest build",
     "format": "prettier --write \"src/**/*.ts\" \"test/**/*.ts\"",
@@ -21,62 +24,62 @@
     "test:e2e": "jest --config ./test/jest-e2e.json"
   },
   "dependencies": {
-    "@nestjs/axios": "^3.0.0",
-    "@nestjs/cache-manager": "^2.0.1",
-    "@nestjs/common": "^9.0.0",
-    "@nestjs/config": "^2.3.2",
-    "@nestjs/core": "^9.0.0",
-    "@nestjs/platform-fastify": "^9.4.2",
-    "@nestjs/schedule": "^3.0.1",
-    "@nestjs/typeorm": "^10.0.0",
-    "axios": "^1.4.0",
-    "big.js": "^6.2.1",
-    "bitcoin-address-validation": "^2.2.1",
-    "bitcoinjs-lib": "^6.1.3",
-    "bitcoinjs-message": "^2.2.0",
+    "@nestjs/axios": "^4.0.1",
+    "@nestjs/cache-manager": "^3.1.2",
+    "@nestjs/common": "^11.1.19",
+    "@nestjs/config": "^4.0.4",
+    "@nestjs/core": "^11.1.19",
+    "@nestjs/platform-fastify": "^11.1.19",
+    "@nestjs/schedule": "^6.1.3",
+    "@nestjs/typeorm": "^11.0.1",
+    "@scure/btc-signer": "^2.2.0",
+    "axios": "^1.16.0",
+    "better-sqlite3": "^12.9.0",
+    "bitcoin-address-validation": "^2.2.3",
+    "bitcoinjs-lib": "^6.1.7",
     "bs58": "^5.0.0",
-    "cache-manager": "^5.2.3",
+    "cache-manager": "^7.2.8",
     "class-transformer": "^0.5.1",
-    "class-validator": "^0.14.0",
-    "discord.js": "^14.11.0",
+    "class-validator": "^0.14.4",
+    "discord.js": "^14.26.4",
     "merkle-lib": "^2.0.10",
-    "node-telegram-bot-api": "^0.61.0",
-    "pg": "^8.11.3",
+    "pg": "^8.20.0",
     "pg-pubsub": "^0.8.1",
-    "reflect-metadata": "^0.1.13",
-    "rpc-bitcoin": "^2.0.0",
-    "rxjs": "^7.2.0",
-    "sqlite3": "^5.1.6",
-    "tiny-secp256k1": "^2.2.3",
-    "typeorm": "^0.3.17",
+    "reflect-metadata": "^0.2.2",
+    "rxjs": "^7.8.2",
+    "tiny-secp256k1": "^2.2.4",
+    "typeorm": "^0.3.28",
     "zeromq": "6.0.0-beta.19"
   },
   "devDependencies": {
-    "@nestjs/cli": "^9.0.0",
-    "@nestjs/schematics": "^9.0.0",
-    "@nestjs/testing": "^9.0.0",
-    "@types/big.js": "^6.1.6",
+    "@nestjs/cli": "^11.0.21",
+    "@nestjs/schematics": "^11.1.0",
+    "@nestjs/testing": "^11.1.19",
     "@types/cron": "^2.0.1",
-    "@types/express": "^4.17.13",
-    "@types/jest": "29.5.1",
-    "@types/node": "^18.16.12",
-    "@types/node-telegram-bot-api": "^0.61.6",
-    "@types/supertest": "^2.0.11",
+    "@types/express": "^4.17.25",
+    "@types/jest": "^29.5.14",
+    "@types/node": "^18.19.130",
+    "@types/supertest": "^7.2.0",
     "@typescript-eslint/eslint-plugin": "^5.0.0",
     "@typescript-eslint/parser": "^5.0.0",
     "eslint": "^8.0.1",
-    "eslint-config-prettier": "^8.3.0",
-    "eslint-plugin-prettier": "^4.0.0",
-    "jest": "29.5.0",
-    "patch-package": "8.0.0",
-    "prettier": "^2.3.2",
+    "eslint-config-prettier": "^10.1.8",
+    "eslint-plugin-prettier": "^5.5.5",
+    "jest": "^29.7.0",
+    "patch-package": "^8.0.1",
+    "prettier": "^3.8.3",
     "source-map-support": "^0.5.20",
-    "supertest": "^6.1.3",
-    "ts-jest": "29.1.0",
-    "ts-loader": "^9.2.3",
-    "ts-node": "^10.0.0",
+    "supertest": "^7.2.2",
+    "ts-jest": "^29.4.9",
+    "ts-loader": "^9.5.7",
+    "ts-node": "^10.9.2",
     "tsconfig-paths": "4.2.0",
-    "typescript": "^5.0.0"
+    "typescript": "^5.9.3"
+  },
+  "overrides": {
+    "@fastify/middie": "^9.3.2",
+    "fastify": "^5.8.5",
+    "path-to-regexp": "^8.4.2"
   },
   "jest": {
     "moduleFileExtensions": [
@@ -87,8 +90,18 @@
     "rootDir": "src",
     "testRegex": ".*\\.spec\\.ts$",
     "transform": {
-      "^.+\\.(t|j)s$": "ts-jest"
+      "^.+\\.(t|j)s$": [
+        "ts-jest",
+        {
+          "tsconfig": {
+            "allowJs": true
+          }
+        }
+      ]
     },
+    "transformIgnorePatterns": [
+      "node_modules/(?!(@scure|@noble|micro-packed))"
+    ],
     "collectCoverageFrom": [
       "**/*.(t|j)s"
     ],

patches/rpc-bitcoin+2.0.0.patch

@@ -1,26 +0,0 @@
-diff --git a/node_modules/rpc-bitcoin/build/src/rpc.d.ts b/node_modules/rpc-bitcoin/build/src/rpc.d.ts
-index d25d732..ce4eb22 100644
---- a/node_modules/rpc-bitcoin/build/src/rpc.d.ts
-+++ b/node_modules/rpc-bitcoin/build/src/rpc.d.ts
-@@ -6,7 +6,7 @@ export declare type RPCIniOptions = RESTIniOptions & {
-   fullResponse?: boolean;
- };
- export declare type JSONRPC = {
--  jsonrpc?: string | number;
-+  jsonrpc?: string;
-   id?: string | number;
-   method: string;
-   params?: object;
-diff --git a/node_modules/rpc-bitcoin/build/src/rpc.js b/node_modules/rpc-bitcoin/build/src/rpc.js
-index 7fec7aa..3bee5fc 100644
---- a/node_modules/rpc-bitcoin/build/src/rpc.js
-+++ b/node_modules/rpc-bitcoin/build/src/rpc.js
-@@ -12,7 +12,7 @@ class RPCClient extends rest_1.RESTClient {
-   }
-   async rpc(method, params = {}, wallet) {
-     const uri = typeof wallet === "undefined" ? "/" : "wallet/" + wallet;
--    const body = { method, params, jsonrpc: 1.0, id: "rpc-bitcoin" };
-+    const body = { method, params, jsonrpc: "1.0", id: "rpc-bitcoin" };
-     try {
-       const response = await this.batch(body, uri);
-       return this.fullResponse ? response : response.result;

src/ORM/address-settings/address-settings.service.ts

@@ -31,6 +31,24 @@ export class AddressSettingsService {
         return await this.addressSettingsRepository.update({ address }, { bestDifficulty, bestDifficultyUserAgent });
     }
 
+    public async updateBestDifficultyIfHigher(address: string, bestDifficulty: number, bestDifficultyUserAgent: string) {
+        await this.addressSettingsRepository
+            .createQueryBuilder()
+            .insert()
+            .into(AddressSettingsEntity)
+            .values({ address })
+            .orIgnore()
+            .execute();
+
+        return await this.addressSettingsRepository
+            .createQueryBuilder()
+            .update(AddressSettingsEntity)
+            .set({ bestDifficulty, bestDifficultyUserAgent })
+            .where('address = :address', { address })
+            .andWhere('"bestDifficulty" < :bestDifficulty', { bestDifficulty })
+            .execute();
+    }
+
     public async createNew(address: string) {
         return await this.addressSettingsRepository.save({ address });
     }
@@ -46,10 +64,14 @@ export class AddressSettingsService {
     // }
 
     public async resetBestDifficultyAndShares() {
-        return await this.addressSettingsRepository.update({}, {
-            shares: 0,
-            bestDifficulty: 0
-        });
+        return await this.addressSettingsRepository
+            .createQueryBuilder()
+            .update(AddressSettingsEntity)
+            .set({
+                shares: 0,
+                bestDifficulty: 0
+            })
+            .execute();
     }
 
     public async getHighScores() {

src/ORM/blocks/blocks.entity.ts

@@ -1,11 +1,12 @@
-import { Column, Entity, PrimaryGeneratedColumn } from 'typeorm';
+import { Column, Entity } from 'typeorm';
 
+import { PrimaryGeneratedBigIntColumn } from '../utils/PrimaryGeneratedBigIntColumn';
 import { TrackedEntity } from '../utils/TrackedEntity.entity';
 
 @Entity()
 export class BlocksEntity extends TrackedEntity {
 
-    @PrimaryGeneratedColumn({type: 'bigint'})
+    @PrimaryGeneratedBigIntColumn()
     id: number;
 
     @Column()
@@ -23,4 +24,4 @@ export class BlocksEntity extends TrackedEntity {
     @Column()
     blockData: string;
 
-}
+}

src/ORM/client-statistics/client-statistics.entity.ts

@@ -1,6 +1,7 @@
-import { Column, Entity, Index, ManyToOne, PrimaryGeneratedColumn } from 'typeorm';
+import { Column, Entity, Index, ManyToOne } from 'typeorm';
 
 import { ClientEntity } from '../client/client.entity';
+import { PrimaryGeneratedBigIntColumn } from '../utils/PrimaryGeneratedBigIntColumn';
 import { TrackedEntity } from '../utils/TrackedEntity.entity';
 
 @Entity()
@@ -8,7 +9,7 @@ import { TrackedEntity } from '../utils/TrackedEntity.entity';
 @Index(["clientId", "time"])
 export class ClientStatisticsEntity extends TrackedEntity {
 
-    @PrimaryGeneratedColumn({type: 'bigint'})
+    @PrimaryGeneratedBigIntColumn()
     id: number;
 
     @Column({ length: 62, type: 'varchar' })
@@ -44,4 +45,4 @@ export class ClientStatisticsEntity extends TrackedEntity {
     public clientId: string;
 
 
-}
+}

src/ORM/client-statistics/client-statistics.service.ts

@@ -259,6 +259,6 @@ export class ClientStatisticsService {
     }
 
     public async deleteAll() {
-        return await this.clientStatisticsRepository.delete({})
+        return await this.clientStatisticsRepository.clear()
     }
-}
+}

src/ORM/client/client.entity.ts

@@ -30,7 +30,7 @@ export class ClientEntity extends TrackedEntity {
     userAgent: string;
 
 
-    @Column({ type: 'timestamp' })
+    @Column()
     startTime: Date;
 
     @Column({ type: 'decimal', default: 0 })
@@ -46,4 +46,3 @@ export class ClientEntity extends TrackedEntity {
     statistics: ClientStatisticsEntity[]
 
 }
-

src/ORM/client/client.service.ts

@@ -140,6 +140,17 @@ export class ClientService {
     public async updateBestDifficulty(id: string, bestDifficulty: number) {
         return await this.clientRepository.update({ id }, { bestDifficulty });
     }
+
+    public async updateBestDifficultyIfHigher(id: string, bestDifficulty: number) {
+        return await this.clientRepository
+            .createQueryBuilder()
+            .update(ClientEntity)
+            .set({ bestDifficulty })
+            .where('id = :id', { id })
+            .andWhere('"bestDifficulty" < :bestDifficulty', { bestDifficulty })
+            .execute();
+    }
+
     public async connectedClientCount(): Promise<number> {
         return await this.clientRepository.count();
     }
@@ -173,7 +184,10 @@ export class ClientService {
     }
 
     public async deleteAll() {
-        return await this.clientRepository.softDelete({})
+        return await this.clientRepository
+            .createQueryBuilder()
+            .softDelete()
+            .execute();
     }
 
     // public async getUserAgents() {
@@ -188,4 +202,4 @@ export class ClientService {
     //     return result;
     // }
 
-}
+}

src/ORM/home-graph/home-graph.entity.ts

@@ -1,9 +1,11 @@
-import { Column, Entity, PrimaryGeneratedColumn } from 'typeorm';
+import { Column, Entity } from 'typeorm';
+
+import { PrimaryGeneratedBigIntColumn } from '../utils/PrimaryGeneratedBigIntColumn';
 
 @Entity()
 export class HomeGraphEntity {
 
-    @PrimaryGeneratedColumn({type: 'bigint'})
+    @PrimaryGeneratedBigIntColumn()
     id: number;
 
     @Column({ type: 'bigint' })
@@ -11,4 +13,4 @@ export class HomeGraphEntity {
 
     @Column({ type: 'bigint' })
     data: number;
-}
+}

src/ORM/telegram-subscriptions/telegram-subscriptions.entity.ts

@@ -1,11 +1,12 @@
-import { Column, Entity, Index, PrimaryGeneratedColumn } from 'typeorm';
+import { Column, Entity, Index } from 'typeorm';
 
+import { PrimaryGeneratedBigIntColumn } from '../utils/PrimaryGeneratedBigIntColumn';
 import { TrackedEntity } from '../utils/TrackedEntity.entity';
 
 @Entity()
 export class TelegramSubscriptionsEntity extends TrackedEntity {
 
-    @PrimaryGeneratedColumn({type: 'bigint'})
+    @PrimaryGeneratedBigIntColumn()
     id: number;
 
     @Index()
@@ -16,4 +17,4 @@ export class TelegramSubscriptionsEntity extends TrackedEntity {
     telegramChatId: number;
 
 
-}
+}

src/ORM/utils/PrimaryGeneratedBigIntColumn.ts

@@ -0,0 +1,5 @@
+import { PrimaryGeneratedColumn } from 'typeorm';
+
+export const PrimaryGeneratedBigIntColumn = () => PrimaryGeneratedColumn({
+    type: process.env.NODE_ENV === 'test' ? 'integer' : 'bigint'
+});

src/ORM/utils/TrackedEntity.entity.ts

@@ -1,12 +1,12 @@
 import { CreateDateColumn, DeleteDateColumn, UpdateDateColumn } from 'typeorm';
 
 export abstract class TrackedEntity {
-    @DeleteDateColumn({ nullable: true, type: 'timestamp' })
+    @DeleteDateColumn({ nullable: true })
     public deletedAt?: Date;
 
-    @CreateDateColumn({ type: 'timestamp' })
+    @CreateDateColumn()
     public createdAt?: Date
 
-    @UpdateDateColumn({ type: 'timestamp' })
+    @UpdateDateColumn()
     public updatedAt?: Date
-}
+}

src/app.controller.ts

@@ -11,6 +11,7 @@ import { ClientService } from './ORM/client/client.service';
 import { HomeGraphService } from './ORM/home-graph/home-graph.service';
 import { BitcoinRpcService } from './services/bitcoin-rpc.service';
 import { UserAgentReportView } from './ORM/_views/user-agent-report/user-agent-report.view';
+import { StratumV2Service } from './services/stratum-v2.service';
 
 @Controller()
 export class AppController {
@@ -25,7 +26,8 @@ export class AppController {
     private readonly bitcoinRpcService: BitcoinRpcService,
     private readonly homeGraphService: HomeGraphService,
     private readonly addressSettingsService: AddressSettingsService,
-    private readonly userAgentReportService: UserAgentReportService
+    private readonly userAgentReportService: UserAgentReportService,
+    private readonly stratumV2Service: StratumV2Service
   ) { }
 
   @Get('info')
@@ -42,6 +44,7 @@ export class AppController {
 
     const blockData = await this.blocksService.getFoundBlocks();
     const highScores = await this.addressSettingsService.getHighScores();
+    const poolAuthority = await this.stratumV2Service.getPoolAuthorityPublicKey();
 
     const other: {
       count: number,
@@ -72,6 +75,10 @@ export class AppController {
       blockData,
       userAgents,
       highScores,
+      sv2: {
+        poolAuthorityPublicKey: poolAuthority.publicKey,
+        authorityKeyConfigured: poolAuthority.configured
+      },
       uptime: this.uptime
     };
 

src/app.module.ts

@@ -34,6 +34,7 @@ import { DiscordService } from './services/discord.service';
 import { NotificationService } from './services/notification.service';
 import { StratumV1JobsService } from './services/stratum-v1-jobs.service';
 import { StratumV1Service } from './services/stratum-v1.service';
+import { StratumV2Service } from './services/stratum-v2.service';
 import { TelegramService } from './services/telegram.service';
 
 
@@ -100,6 +101,7 @@ const ORMModules = [
         NotificationService,
         BitcoinAddressValidator,
         StratumV1JobsService,
+        StratumV2Service,
         BTCPayService,
         BraiinsService
     ],

src/controllers/address/address.controller.ts

@@ -1,5 +1,4 @@
 import { Controller, Patch } from '@nestjs/common';
-import * as bitcoinMessage from 'bitcoinjs-message';
 
 
 @Controller('address')
@@ -7,16 +6,6 @@ export class AddressController {
 
     @Patch('settings')
     async settings() {
-
-        const publicKey = '...'; // Public key corresponding to the private key used for signing
-        const message = '...'; // The message that was signed
-        const signature = '...'; // The signature of the message
-
-        const isValid: boolean = bitcoinMessage.verify(message, publicKey, signature);
-        if (isValid) {
-            console.log('Signature is valid!');
-        } else {
-            console.log('Signature is not valid!');
-        }
+        return;
     }
 }

src/controllers/client/client.controller.spec.ts

@@ -13,8 +13,8 @@ describe('ClientController', () => {
     const module: TestingModule = await Test.createTestingModule({
       imports: [
         TypeOrmModule.forRoot({
-          type: 'sqlite',
-          database: './DB/public-pool.test.sqlite',
+          type: 'better-sqlite3',
+          database: ':memory:',
           synchronize: true,
           autoLoadEntities: true,
           cache: true,

src/models/MiningJob.spec.ts

@@ -0,0 +1,128 @@
+import * as bitcoinjs from 'bitcoinjs-lib';
+import { BehaviorSubject, firstValueFrom } from 'rxjs';
+
+import { MockRecording1 } from '../../test/models/MockRecording1';
+import { StratumV1JobsService } from '../services/stratum-v1-jobs.service';
+import { MiningJob } from './MiningJob';
+
+describe('MiningJob', () => {
+    let jobTemplate;
+    let job: MiningJob;
+
+    beforeEach(async () => {
+        jest.useFakeTimers();
+        jest.setSystemTime(new Date(parseInt(MockRecording1.TIME, 16) * 1000));
+
+        const blockTemplate$ = new BehaviorSubject(MockRecording1.BLOCK_TEMPLATE);
+        const bitcoinRpcService = {
+            newBlockTemplate$: blockTemplate$.asObservable(),
+            miningInfo: { blocks: MockRecording1.BLOCK_TEMPLATE.height }
+        };
+        jest.spyOn(console, 'log').mockImplementation(() => undefined);
+
+        const jobsService = new StratumV1JobsService(bitcoinRpcService as any);
+        jobTemplate = await firstValueFrom(jobsService.newMiningJob$);
+        job = new MiningJob(
+            bitcoinjs.networks.testnet,
+            '1',
+            [{ address: 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4', percent: 100 }],
+            jobTemplate
+        );
+    });
+
+    afterEach(() => {
+        jest.restoreAllMocks();
+        jest.useRealTimers();
+    });
+
+    it('should split coinbase around 12 bytes of extranonce space', () => {
+        const notify = JSON.parse(job.response(jobTemplate));
+        const coinbasePart1 = notify.params[2];
+        const coinbasePart2 = notify.params[3];
+        const extraNonce1 = '57a6f098';
+        const extraNonce2 = 'c708000000000000';
+        const coinbase = bitcoinjs.Transaction.fromHex(`${coinbasePart1}${extraNonce1}${extraNonce2}${coinbasePart2}`);
+
+        expect(Buffer.byteLength(extraNonce1 + extraNonce2, 'hex')).toBe(12);
+        expect(coinbase.ins[0].script.toString('hex')).toContain(`${extraNonce1}${extraNonce2}`);
+        expect(coinbase.ins[0].script.toString('hex').endsWith(`${extraNonce1}${extraNonce2}`)).toBe(true);
+    });
+
+    it('should expose coinbase prefix and suffix buffers for SV2 extended jobs', () => {
+        const notify = JSON.parse(job.response(jobTemplate));
+        const extraNonce1 = '57a6f098';
+        const extraNonce2 = 'c708000000000000';
+        const fromNotify = Buffer.from(`${notify.params[2]}${extraNonce1}${extraNonce2}${notify.params[3]}`, 'hex');
+        const fromBuffers = Buffer.concat([
+            job.getCoinbasePrefixBuffer(),
+            Buffer.from(`${extraNonce1}${extraNonce2}`, 'hex'),
+            job.getCoinbaseSuffixBuffer(),
+        ]);
+
+        expect(fromBuffers).toEqual(fromNotify);
+        expect(bitcoinjs.Transaction.fromBuffer(fromBuffers).ins[0].script.toString('hex'))
+            .toContain(`${extraNonce1}${extraNonce2}`);
+    });
+
+    it('should update block nonce, timestamp, version mask, and coinbase script', () => {
+        const extraNonce1 = '57a6f098';
+        const extraNonce2 = 'c708000000000000';
+        const timestamp = parseInt(MockRecording1.TIME, 16);
+        const originalMerkleRoot = Buffer.from(jobTemplate.block.merkleRoot);
+
+        const updatedBlock = job.copyAndUpdateBlock(
+            jobTemplate,
+            parseInt('00002000', 16),
+            parseInt('ed460d91', 16),
+            extraNonce1,
+            extraNonce2,
+            timestamp
+        );
+
+        expect(updatedBlock.nonce).toBe(parseInt('ed460d91', 16));
+        expect(updatedBlock.timestamp).toBe(timestamp);
+        expect(updatedBlock.version).toBe(jobTemplate.block.version ^ parseInt('00002000', 16));
+        expect(updatedBlock.transactions[0].ins[0].script.toString('hex').endsWith(`${extraNonce1}${extraNonce2}`)).toBe(true);
+        expect(updatedBlock.merkleRoot.equals(originalMerkleRoot)).toBe(false);
+    });
+
+    it('should leave block version unchanged without a version mask', () => {
+        const updatedBlock = job.copyAndUpdateBlock(
+            jobTemplate,
+            0,
+            parseInt('ed460d91', 16),
+            '57a6f098',
+            'c708000000000000',
+            parseInt(MockRecording1.TIME, 16)
+        );
+
+        expect(updatedBlock.version).toBe(jobTemplate.block.version);
+    });
+
+    it('should build the same header as the full block update path', () => {
+        const versionMask = parseInt('00002000', 16);
+        const nonce = parseInt('ed460d91', 16);
+        const extraNonce1 = '57a6f098';
+        const extraNonce2 = 'c708000000000000';
+        const timestamp = parseInt(MockRecording1.TIME, 16);
+
+        const updatedBlock = job.copyAndUpdateBlock(
+            jobTemplate,
+            versionMask,
+            nonce,
+            extraNonce1,
+            extraNonce2,
+            timestamp
+        );
+        const fastHeader = job.buildHeaderBuffer(
+            jobTemplate,
+            versionMask,
+            nonce,
+            extraNonce1,
+            extraNonce2,
+            timestamp
+        );
+
+        expect(fastHeader.equals(updatedBlock.toBuffer(true))).toBe(true);
+    });
+});

src/models/MiningJob.ts

@@ -4,6 +4,7 @@ import * as bitcoinjs from 'bitcoinjs-lib';
 import { IJobTemplate } from '../services/stratum-v1-jobs.service';
 import { eResponseMethod } from './enums/eResponseMethod';
 import { IMiningNotify } from './stratum-messages/IMiningNotify';
+import { TOTAL_EXTRANONCE_SIZE_BYTES } from './stratum.constants';
 
 
 interface AddressObject {
@@ -15,6 +16,9 @@ export class MiningJob {
     private coinbaseTransaction: bitcoinjs.Transaction;
     private coinbasePart1: string;
     private coinbasePart2: string;
+    private coinbasePart1Buffer: Buffer;
+    private coinbasePart2Buffer: Buffer;
+    private merkleBranchBuffers: Buffer[];
 
     public jobTemplateId: string;
     public networkDifficulty: number;
@@ -29,6 +33,7 @@ export class MiningJob {
 
         this.creation = new Date().getTime();
         this.jobTemplateId = jobTemplate.blockData.id;
+        this.merkleBranchBuffers = jobTemplate.merkle_branch.map(branch => Buffer.from(branch, 'hex'));
 
         this.coinbaseTransaction = this.createCoinbaseTransaction(payoutInformation, jobTemplate.blockData.coinbasevalue);
 
@@ -50,7 +55,7 @@ export class MiningJob {
         const blockHeightLengthByte = Buffer.from([blockHeightEncoded.length]);
 
         // generate padding and take length of encode blockHeight into account
-        const padding = Buffer.alloc(8 + (3 - blockHeightEncoded.length), 0)
+        const padding = Buffer.alloc(TOTAL_EXTRANONCE_SIZE_BYTES + (3 - blockHeightEncoded.length), 0)
 
         // build the script
         this.coinbaseTransaction.ins[0].script = Buffer.concat([blockHeightLengthByte, blockHeightEncoded, extra, padding])
@@ -65,12 +70,51 @@ export class MiningJob {
 
         const partOneIndex = serializedCoinbaseTx.indexOf(inputScript) + inputScript.length;
 
-        this.coinbasePart1 = serializedCoinbaseTx.slice(0, partOneIndex - 16);
+        this.coinbasePart1 = serializedCoinbaseTx.slice(0, partOneIndex - (TOTAL_EXTRANONCE_SIZE_BYTES * 2));
         this.coinbasePart2 = serializedCoinbaseTx.slice(partOneIndex);
+        this.coinbasePart1Buffer = Buffer.from(this.coinbasePart1, 'hex');
+        this.coinbasePart2Buffer = Buffer.from(this.coinbasePart2, 'hex');
 
 
     }
 
+    public cloneCoinbaseTransaction(): bitcoinjs.Transaction {
+        return bitcoinjs.Transaction.fromBuffer(this.coinbaseTransaction.toBuffer());
+    }
+
+    public getCoinbasePrefixBuffer(): Buffer {
+        return Buffer.from(this.coinbasePart1Buffer);
+    }
+
+    public getCoinbaseSuffixBuffer(): Buffer {
+        return Buffer.from(this.coinbasePart2Buffer);
+    }
+
+    public buildHeaderBuffer(jobTemplate: IJobTemplate, versionMask: number, nonce: number, extraNonce: string, extraNonce2: string, timestamp: number): Buffer {
+        const coinbaseBuffer = Buffer.concat([
+            this.coinbasePart1Buffer,
+            Buffer.from(`${extraNonce}${extraNonce2}`, 'hex'),
+            this.coinbasePart2Buffer,
+        ]);
+        const coinbaseHash = bitcoinjs.crypto.hash256(coinbaseBuffer);
+        const merkleRoot = this.calculateMerkleRootHash(coinbaseHash, this.merkleBranchBuffers);
+
+        let version = jobTemplate.block.version;
+        if (versionMask !== undefined && versionMask != 0) {
+            version = version ^ versionMask;
+        }
+
+        const header = Buffer.alloc(80);
+        header.writeInt32LE(version, 0);
+        jobTemplate.block.prevHash.copy(header, 4);
+        merkleRoot.copy(header, 36);
+        header.writeUInt32LE(timestamp, 68);
+        header.writeUInt32LE(jobTemplate.block.bits, 72);
+        header.writeUInt32LE(nonce, 76);
+
+        return header;
+    }
+
     public copyAndUpdateBlock(jobTemplate: IJobTemplate, versionMask: number, nonce: number, extraNonce: string, extraNonce2: string, timestamp: number): bitcoinjs.Block {
 
         const testBlock = Object.assign(new bitcoinjs.Block(), jobTemplate.block);
@@ -78,7 +122,7 @@ export class MiningJob {
             return Object.assign(new bitcoinjs.Transaction(), tx);
         });
 
-        testBlock.transactions[0] = this.coinbaseTransaction;
+        testBlock.transactions[0] = this.cloneCoinbaseTransaction();
 
         testBlock.nonce = nonce;
 
@@ -90,10 +134,10 @@ export class MiningJob {
         // set the nonces
         const nonceScript = testBlock.transactions[0].ins[0].script.toString('hex');
 
-        testBlock.transactions[0].ins[0].script = Buffer.from(`${nonceScript.substring(0, nonceScript.length - 16)}${extraNonce}${extraNonce2}`, 'hex');
+        testBlock.transactions[0].ins[0].script = Buffer.from(`${nonceScript.substring(0, nonceScript.length - (TOTAL_EXTRANONCE_SIZE_BYTES * 2))}${extraNonce}${extraNonce2}`, 'hex');
 
         //recompute the root since we updated the coinbase script with the nonces
-        testBlock.merkleRoot = this.calculateMerkleRootHash(testBlock.transactions[0].getHash(false), jobTemplate.merkle_branch);
+        testBlock.merkleRoot = this.calculateMerkleRootHash(testBlock.transactions[0].getHash(false), this.merkleBranchBuffers);
 
 
         testBlock.timestamp = timestamp;
@@ -102,14 +146,14 @@ export class MiningJob {
     }
 
 
-    private calculateMerkleRootHash(newRoot: Buffer, merkleBranches: string[]): Buffer {
+    private calculateMerkleRootHash(newRoot: Buffer, merkleBranches: Buffer[]): Buffer {
 
         const bothMerkles = Buffer.alloc(64);
 
         bothMerkles.set(newRoot);
 
         for (let i = 0; i < merkleBranches.length; i++) {
-            bothMerkles.set(Buffer.from(merkleBranches[i], 'hex'), 32);
+            bothMerkles.set(merkleBranches[i], 32);
             newRoot = bitcoinjs.crypto.hash256(bothMerkles);
             bothMerkles.set(newRoot);
         }

src/models/StratumV1Client.spec.ts

@@ -8,6 +8,7 @@ import { DataSource } from 'typeorm';
 import { MockRecording1 } from '../../test/models/MockRecording1';
 import { AddressSettingsModule } from '../ORM/address-settings/address-settings.module';
 import { AddressSettingsService } from '../ORM/address-settings/address-settings.service';
+import { BlocksEntity } from '../ORM/blocks/blocks.entity';
 import { BlocksService } from '../ORM/blocks/blocks.service';
 import { ClientStatisticsEntity } from '../ORM/client-statistics/client-statistics.entity';
 import { ClientStatisticsModule } from '../ORM/client-statistics/client-statistics.module';
@@ -18,8 +19,10 @@ import { ClientService } from '../ORM/client/client.service';
 import { BitcoinRpcService as MockBitcoinRpcService } from '../services/bitcoin-rpc.service';
 import { NotificationService } from '../services/notification.service';
 import { StratumV1JobsService } from '../services/stratum-v1-jobs.service';
-import { IMiningInfo } from './bitcoin-rpc/IMiningInfo';
+import { IBlockTemplate } from './bitcoin-rpc/IBlockTemplate';
+import { MiningJob } from './MiningJob';
 import { StratumV1Client } from './StratumV1Client';
+import { MiningSubmitMessage } from './stratum-messages/MiningSubmitMessage';
 
 
 
@@ -50,8 +53,12 @@ describe('StratumV1Client', () => {
     let client: StratumV1Client;
 
     let socketEmitter: (...args: any[]) => void;
+    const emitMessage = (message: string) => socketEmitter(Buffer.from(`${message}\n`));
+    let consoleLogSpy: jest.SpyInstance;
+    let consoleErrorSpy: jest.SpyInstance;
+    let consoleWarnSpy: jest.SpyInstance;
 
-    let newBlockEmitter: BehaviorSubject<IMiningInfo> = new BehaviorSubject(null);
+    let newBlockEmitter: BehaviorSubject<IBlockTemplate> = new BehaviorSubject(MockRecording1.BLOCK_TEMPLATE);
 
     let moduleRef: TestingModule;
 
@@ -59,12 +66,13 @@ describe('StratumV1Client', () => {
         moduleRef = await Test.createTestingModule({
             imports: [
                 TypeOrmModule.forRoot({
-                    type: 'sqlite',
-                    database: './DB/public-pool.test.sqlite',
+                    type: 'better-sqlite3',
+                    database: ':memory:',
                     synchronize: true,
                     autoLoadEntities: true,
                     cache: true,
-                    logging: false
+                    logging: false,
+                    entities: [ClientEntity, ClientStatisticsEntity, BlocksEntity]
                 }),
                 ClientModule,
                 ClientStatisticsModule,
@@ -94,23 +102,41 @@ describe('StratumV1Client', () => {
 
     beforeEach(async () => {
 
-        console.log('NEW TEST')
+        jest.useFakeTimers({ advanceTimers: true })
+        jest.setSystemTime(new Date(parseInt(MockRecording1.TIME, 16) * 1000));
+        consoleLogSpy = jest.spyOn(console, 'log').mockImplementation(() => undefined);
+        consoleErrorSpy = jest.spyOn(console, 'error').mockImplementation(() => undefined);
+        consoleWarnSpy = jest.spyOn(console, 'warn').mockImplementation(() => undefined);
 
         clientService = moduleRef.get<ClientService>(ClientService);
 
         const dataSource = moduleRef.get<DataSource>(DataSource);
 
-        dataSource.getRepository(ClientEntity).delete({});
-        dataSource.getRepository(ClientStatisticsEntity).delete({});
+        await dataSource.getRepository(ClientStatisticsEntity).clear();
+        await dataSource.getRepository(ClientEntity).clear();
+        await dataSource.getRepository(BlocksEntity).clear();
 
 
         clientStatisticsService = moduleRef.get<ClientStatisticsService>(ClientStatisticsService);
 
         configService = moduleRef.get<ConfigService>(ConfigService);
+        (configService.get as jest.Mock).mockImplementation((key: string) => {
+            switch (key) {
+                case 'DEV_FEE_ADDRESS':
+                    return 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4';
+                case 'NETWORK':
+                    return 'testnet';
+            }
+            return null;
+        });
+        (StratumV1Client as any).blockedUserAgentLogState.clear();
+        (StratumV1Client as any).validationErrorLogState.clear();
 
-        bitcoinRpcService = new MockBitcoinRpcService(null);
-        jest.spyOn(bitcoinRpcService, 'getBlockTemplate').mockReturnValue(Promise.resolve(MockRecording1.BLOCK_TEMPLATE));
-        bitcoinRpcService.newBlock$ = newBlockEmitter.asObservable();
+        bitcoinRpcService = {
+            newBlockTemplate$: newBlockEmitter.asObservable(),
+            miningInfo: { blocks: MockRecording1.BLOCK_TEMPLATE.height },
+            SUBMIT_BLOCK: jest.fn().mockResolvedValue(null)
+        } as any;
 
 
         stratumV1JobsService = new StratumV1JobsService(bitcoinRpcService);
@@ -126,8 +152,15 @@ describe('StratumV1Client', () => {
         });
 
         socket.end = jest.fn();
+        jest.spyOn(socket, 'destroy').mockImplementation(() => socket);
 
         const addressSettings = moduleRef.get<AddressSettingsService>(AddressSettingsService);
+        notificationService = {
+            notifySubscribersBlockFound: jest.fn().mockResolvedValue(undefined)
+        } as any;
+        blocksService = {
+            save: jest.fn().mockResolvedValue(undefined)
+        } as any;
 
 
         client = new StratumV1Client(
@@ -143,12 +176,15 @@ describe('StratumV1Client', () => {
         );
 
         client.extraNonceAndSessionId = MockRecording1.EXTRA_NONCE;
+        jest.spyOn(client as any, 'getRandomHexString').mockReturnValue(MockRecording1.EXTRA_NONCE);
 
-        jest.useFakeTimers({ advanceTimers: true })
     });
 
     afterEach(async () => {
         client.destroy();
+        consoleLogSpy.mockRestore();
+        consoleErrorSpy.mockRestore();
+        consoleWarnSpy.mockRestore();
         jest.useRealTimers();
     })
 
@@ -158,7 +194,7 @@ describe('StratumV1Client', () => {
     });
 
     it('should close socket on invalid JSON', () => {
-        socketEmitter(Buffer.from('INVALID'));
+        emitMessage('INVALID');
         jest.spyOn(socket, 'destroy');
         expect(socket.on).toHaveBeenCalled();
     });
@@ -167,21 +203,88 @@ describe('StratumV1Client', () => {
         jest.spyOn(socket, 'write').mockImplementation((data) => true);
 
         expect(socket.on).toHaveBeenCalled();
-        socketEmitter(Buffer.from(MockRecording1.MINING_SUBSCRIBE));
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
 
         await new Promise((r) => setTimeout(r, 1));
 
-        expect(socket.write).toHaveBeenCalledWith(`{"id":1,"error":null,"result":[[["mining.notify","${client.extraNonceAndSessionId}"]],"${client.extraNonceAndSessionId}",4]}\n`, expect.any(Function));
+        expect(socket.write).toHaveBeenCalledWith(`{"id":1,"error":null,"result":[[["mining.notify","${client.extraNonceAndSessionId}"]],"${client.extraNonceAndSessionId}",8]}\n`, expect.any(Function));
 
     });
 
+    it('should block non-compliant user agents on subscribe without allocating a session', async () => {
+        (configService.get as jest.Mock).mockImplementation((key: string) => {
+            switch (key) {
+                case 'NON_COMPLIANT_USER_AGENTS':
+                    return 'NMMiner';
+                case 'DEV_FEE_ADDRESS':
+                    return 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4';
+                case 'NETWORK':
+                    return 'testnet';
+            }
+            return null;
+        });
+        jest.spyOn(socket, 'write').mockImplementation((data) => true);
+
+        emitMessage(`{"id":1,"method":"mining.subscribe","params":["NMMiner/1.0"]}`);
+        await new Promise((r) => setTimeout(r, 1));
+
+        expect(socket.destroy).toHaveBeenCalled();
+        expect(socket.write).not.toHaveBeenCalled();
+        expect((client as any).statistics).toBeUndefined();
+        expect(consoleLogSpy).toHaveBeenCalledWith('Blocked non-compliant connection from userAgent: NMMiner');
+    });
+
+    it('should throttle repeated non-compliant user agent logs', async () => {
+        (configService.get as jest.Mock).mockImplementation((key: string) => {
+            switch (key) {
+                case 'NON_COMPLIANT_USER_AGENTS':
+                    return 'NMMiner';
+                case 'DEV_FEE_ADDRESS':
+                    return 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4';
+                case 'NETWORK':
+                    return 'testnet';
+            }
+            return null;
+        });
+        jest.spyOn(socket, 'write').mockImplementation((data) => true);
+
+        emitMessage(`{"id":1,"method":"mining.subscribe","params":["NMMiner/1.0"]}`);
+        await new Promise((r) => setTimeout(r, 1));
+
+        const secondSocket = new Socket();
+        jest.spyOn(secondSocket, 'on').mockImplementation((event: string, listener: (...args: any[]) => void) => {
+            socketEmitter = listener;
+            return secondSocket;
+        });
+        secondSocket.end = jest.fn();
+        jest.spyOn(secondSocket, 'destroy').mockImplementation(() => secondSocket);
+        const secondClient = new StratumV1Client(
+            secondSocket,
+            stratumV1JobsService,
+            bitcoinRpcService,
+            clientService,
+            clientStatisticsService,
+            notificationService,
+            blocksService,
+            configService,
+            moduleRef.get<AddressSettingsService>(AddressSettingsService)
+        );
+
+        socketEmitter(Buffer.from(`{"id":1,"method":"mining.subscribe","params":["NMMiner/1.0"]}\n`));
+        await new Promise((r) => setTimeout(r, 1));
+
+        expect(secondSocket.destroy).toHaveBeenCalled();
+        expect(consoleLogSpy.mock.calls.filter(call => call[0]?.startsWith('Blocked non-compliant connection'))).toHaveLength(1);
+        await secondClient.destroy();
+    });
+
 
     it('should respond to mining.configure', async () => {
 
         jest.spyOn(socket, 'write').mockImplementation((data) => true);
 
         expect(socket.on).toHaveBeenCalled();
-        socketEmitter(Buffer.from(MockRecording1.MINING_CONFIGURE));
+        emitMessage(MockRecording1.MINING_CONFIGURE);
         await new Promise((r) => setTimeout(r, 1));
         expect(socket.write).toHaveBeenCalledWith(`{"id":2,"error":null,"result":{"version-rolling":true,"version-rolling.mask":"1fffe000"}}\n`, expect.any(Function));
     });
@@ -191,7 +294,7 @@ describe('StratumV1Client', () => {
         jest.spyOn(socket, 'write').mockImplementation((data) => true);
 
         expect(socket.on).toHaveBeenCalled();
-        socketEmitter(Buffer.from(MockRecording1.MINING_AUTHORIZE));
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
         await new Promise((r) => setTimeout(r, 1));
         expect(socket.write).toHaveBeenCalledWith('{"id":3,"error":null,"result":true}\n', expect.any(Function));
     });
@@ -200,7 +303,7 @@ describe('StratumV1Client', () => {
         jest.spyOn(socket, 'write').mockImplementation((data) => true);
 
         expect(socket.on).toHaveBeenCalled();
-        socketEmitter(Buffer.from(MockRecording1.MINING_SUGGEST_DIFFICULTY));
+        emitMessage(MockRecording1.MINING_SUGGEST_DIFFICULTY);
         await new Promise((r) => setTimeout(r, 1));
         expect(socket.write).toHaveBeenCalledWith(`{"id":null,"method":"mining.set_difficulty","params":[512]}\n`, expect.any(Function));
     });
@@ -208,20 +311,22 @@ describe('StratumV1Client', () => {
     it('should set difficulty', async () => {
         jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
 
-        console.log('should set difficulty')
-        socketEmitter(Buffer.from(MockRecording1.MINING_SUBSCRIBE));
-        socketEmitter(Buffer.from(MockRecording1.MINING_AUTHORIZE));
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
         await new Promise((r) => setTimeout(r, 100));
 
-        expect((client as any).write).toHaveBeenCalledWith(`{"id":null,"method":"mining.set_difficulty","params":[16384]}\n`);
+        expect((client as any).write).toHaveBeenCalledWith(`{"id":null,"method":"mining.set_difficulty","params":[100000]}\n`);
 
     });
 
     it('should save client', async () => {
         jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
 
-        socketEmitter(Buffer.from(MockRecording1.MINING_SUBSCRIBE));
-        socketEmitter(Buffer.from(MockRecording1.MINING_AUTHORIZE));
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+        emitMessage(MockRecording1.MINING_SUBMIT);
         await new Promise((r) => setTimeout(r, 100));
 
         const clientCount = await clientService.connectedClientCount();
@@ -244,9 +349,9 @@ describe('StratumV1Client', () => {
         jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
 
 
-        socketEmitter(Buffer.from(MockRecording1.MINING_SUBSCRIBE));
-        socketEmitter(Buffer.from(MockRecording1.MINING_SUGGEST_DIFFICULTY));
-        socketEmitter(Buffer.from(MockRecording1.MINING_AUTHORIZE));
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
 
 
 
@@ -255,10 +360,10 @@ describe('StratumV1Client', () => {
 
 
 
-        expect((client as any).write).lastCalledWith(`{"id":null,"method":"mining.notify","params":["1","171592f223740e92d223f6e68bff25279af7ac4f2246451e0000000200000000","02000000010000000000000000000000000000000000000000000000000000000000000000ffffffff1903c943255c7075626c69632d706f6f6c5c","ffffffff037a90000000000000160014e6f22ca44dc800e9d049621a3b9a42c509f1c4bc3b0f250000000000160014e6f22ca44dc800e9d049621a3b9a42c509f1c4bc0000000000000000266a24aa21a9edbd3d1d916aa0b57326a2d88ebe1b68a1d7c48585f26d8335fe6a94b62755f64c00000000",["175335649d5e8746982969ec88f52e85ac9917106fba5468e699c8879ab974a1","d5644ab3e708c54cd68dc5aedc92b8d3037449687f92ec41ed6e37673d969d4a","5c9ec187517edc0698556cca5ce27e54c96acb014770599ed9df4d4937fbf2b0"],"20000000","192495f8","${MockRecording1.TIME}",false]}\n`);
+        expect((client as any).write).lastCalledWith(`{"id":null,"method":"mining.notify","params":["1","171592f223740e92d223f6e68bff25279af7ac4f2246451e0000000200000000","02000000010000000000000000000000000000000000000000000000000000000000000000ffffffff1b03c943255075626c69632d506f6f6c","ffffffff02b59f250000000000160014e6f22ca44dc800e9d049621a3b9a42c509f1c4bc0000000000000000266a24aa21a9edbd3d1d916aa0b57326a2d88ebe1b68a1d7c48585f26d8335fe6a94b62755f64c00000000",["175335649d5e8746982969ec88f52e85ac9917106fba5468e699c8879ab974a1","d5644ab3e708c54cd68dc5aedc92b8d3037449687f92ec41ed6e37673d969d4a","5c9ec187517edc0698556cca5ce27e54c96acb014770599ed9df4d4937fbf2b0"],"20000000","192495f8","${MockRecording1.TIME}",true]}\n`);
 
 
-        socketEmitter(Buffer.from(MockRecording1.MINING_SUBMIT));
+        emitMessage(MockRecording1.MINING_SUBMIT);
 
         jest.useRealTimers();
         await new Promise((r) => setTimeout(r, 1000));
@@ -268,6 +373,238 @@ describe('StratumV1Client', () => {
 
     });
 
+    it('should use the header-only fast path for non-block submissions', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+        const buildHeaderSpy = jest.spyOn(MiningJob.prototype, 'buildHeaderBuffer');
+        const fullBlockSpy = jest.spyOn(MiningJob.prototype, 'copyAndUpdateBlock');
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        jest.useRealTimers();
+        await new Promise((r) => setTimeout(r, 1000));
+
+        expect(buildHeaderSpy).toHaveBeenCalled();
+        expect(fullBlockSpy).not.toHaveBeenCalled();
+    });
+
+    it('should write accepted response before share accounting finishes', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        let finishAccounting: () => void;
+        const accountingPromise = new Promise<void>((resolve) => {
+            finishAccounting = resolve;
+        });
+        jest.spyOn((client as any).statistics, 'addShares').mockReturnValue(accountingPromise);
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        await Promise.resolve();
+        await Promise.resolve();
+        await Promise.resolve();
+
+        expect((client as any).write).toHaveBeenCalledWith(`{"id":5,"error":null,"result":true}\n`);
+
+        finishAccounting();
+        jest.useRealTimers();
+        await new Promise((r) => setTimeout(r, 100));
+    });
+
+    it('should update address best difficulty through the atomic path', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+        jest.spyOn(client as any, 'calculateDifficulty').mockReturnValue({
+            submissionDifficulty: 1024,
+            submissionHash: 'share'
+        });
+        const addressSettings = moduleRef.get<AddressSettingsService>(AddressSettingsService);
+        const getSettingsSpy = jest.spyOn(addressSettings, 'getSettings');
+        const updateIfHigherSpy = jest.spyOn(addressSettings as any, 'updateBestDifficultyIfHigher').mockResolvedValue({ affected: 1 });
+        const clientUpdateIfHigherSpy = jest.spyOn(clientService as any, 'updateBestDifficultyIfHigher').mockResolvedValue({ affected: 1 });
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        jest.useRealTimers();
+        await new Promise((r) => setTimeout(r, 1000));
+
+        expect(updateIfHigherSpy).toHaveBeenCalledWith(
+            'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4',
+            1024,
+            expect.any(String)
+        );
+        expect(clientUpdateIfHigherSpy).toHaveBeenCalledWith(expect.any(String), 1024);
+        expect(getSettingsSpy).not.toHaveBeenCalled();
+    });
+
+    it('should reject duplicate submissions', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        await new Promise((r) => setTimeout(r, 100));
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        await new Promise((r) => setTimeout(r, 100));
+
+        expect((client as any).write).lastCalledWith(`{"id":5,"result":null,"error":[22,"Duplicate share",""]}\n`);
+    });
+
+    it('should reject submissions for unknown jobs', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+        const hashSpy = jest.spyOn(MiningSubmitMessage.prototype, 'hash');
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(`{"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "ff", "c708000000000000", "64b3f3ec", "ed460d91", "00002000"]}`);
+        await new Promise((r) => setTimeout(r, 100));
+
+        expect((client as any).write).lastCalledWith(`{"id":5,"result":null,"error":[21,"Job not found",""]}\n`);
+        expect(await clientService.connectedClientCount()).toBe(0);
+        expect(hashSpy).not.toHaveBeenCalled();
+    });
+
+    it('should reject submissions when the job template has expired', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+        stratumV1JobsService.blocks = {};
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        await new Promise((r) => setTimeout(r, 100));
+
+        expect((client as any).write).lastCalledWith(`{"id":5,"result":null,"error":[21,"Job Template not found",""]}\n`);
+    });
+
+    it('should reject low difficulty shares', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(MockRecording1.MINING_SUGGEST_DIFFICULTY);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        await new Promise((r) => setTimeout(r, 100));
+
+        expect((client as any).write).lastCalledWith(`{"id":5,"result":null,"error":[23,"Difficulty too low",""]}\n`);
+        expect(await clientService.connectedClientCount()).toBe(0);
+    });
+
+    it('should reject submissions with short extranonce2 values', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(`{"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "c7080000", "64b3f3ec", "ed460d91", "00002000"]}`);
+        await new Promise((r) => setTimeout(r, 100));
+
+        expect((client as any).write).lastCalledWith(expect.stringContaining(`"error":[20,"Mining Submit validation error"`));
+        expect(socket.destroy).toHaveBeenCalled();
+        expect(consoleWarnSpy).toHaveBeenCalledWith(expect.stringContaining('Mining Submit validation error: extraNonce2:isLength'));
+    });
+
+    it('should throttle repeated mining submit validation logs', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(`{"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "c7080000", "64b3f3ec", "ed460d91", "00002000"]}`);
+        await new Promise((r) => setTimeout(r, 100));
+
+        const secondSocket = new Socket();
+        jest.spyOn(secondSocket, 'on').mockImplementation((event: string, listener: (...args: any[]) => void) => {
+            socketEmitter = listener;
+            return secondSocket;
+        });
+        secondSocket.end = jest.fn();
+        jest.spyOn(secondSocket, 'destroy').mockImplementation(() => secondSocket);
+        const secondClient = new StratumV1Client(
+            secondSocket,
+            stratumV1JobsService,
+            bitcoinRpcService,
+            clientService,
+            clientStatisticsService,
+            notificationService,
+            blocksService,
+            configService,
+            moduleRef.get<AddressSettingsService>(AddressSettingsService)
+        );
+        jest.spyOn(secondClient as any, 'write').mockImplementation((data) => Promise.resolve(true));
+        jest.spyOn(secondClient as any, 'getRandomHexString').mockReturnValue(MockRecording1.EXTRA_NONCE);
+
+        socketEmitter(Buffer.from(`${MockRecording1.MINING_SUBSCRIBE}\n`));
+        socketEmitter(Buffer.from(`${MockRecording1.MINING_AUTHORIZE}\n`));
+        await new Promise((r) => setTimeout(r, 100));
+        socketEmitter(Buffer.from(`{"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "c7080000", "64b3f3ec", "ed460d91", "00002000"]}\n`));
+        await new Promise((r) => setTimeout(r, 100));
+
+        expect(consoleWarnSpy.mock.calls.filter(call => call[0]?.startsWith('Mining Submit validation error'))).toHaveLength(1);
+        await secondClient.destroy();
+    });
+
+    it('should close socket when a submit arrives before stratum is initialized', async () => {
+        const endSpy = jest.spyOn(socket, 'end');
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        await new Promise((r) => setTimeout(r, 100));
+
+        expect(endSpy).toHaveBeenCalled();
+    });
+
+    it('should submit and persist found blocks', async () => {
+        jest.spyOn(client as any, 'write').mockImplementation((data) => Promise.resolve(true));
+        jest.spyOn(client as any, 'calculateDifficulty').mockReturnValue({
+            submissionDifficulty: Number.MAX_SAFE_INTEGER,
+            submissionHash: 'block-share'
+        });
+        const addressSettings = moduleRef.get<AddressSettingsService>(AddressSettingsService);
+        jest.spyOn(addressSettings, 'resetBestDifficultyAndShares').mockResolvedValue(undefined);
+
+        emitMessage(MockRecording1.MINING_SUBSCRIBE);
+        emitMessage(`{"id": 4, "method": "mining.suggest_difficulty", "params": [0]}`);
+        emitMessage(MockRecording1.MINING_AUTHORIZE);
+        await new Promise((r) => setTimeout(r, 100));
+
+        emitMessage(MockRecording1.MINING_SUBMIT);
+        jest.useRealTimers();
+        await new Promise((r) => setTimeout(r, 1000));
+
+        expect(bitcoinRpcService.SUBMIT_BLOCK).toHaveBeenCalledWith(expect.any(String));
+        expect(blocksService.save).toHaveBeenCalledWith(expect.objectContaining({
+            height: MockRecording1.BLOCK_TEMPLATE.height,
+            minerAddress: 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4',
+            worker: 'bitaxe3',
+            sessionId: MockRecording1.EXTRA_NONCE,
+            blockData: expect.any(String)
+        }));
+        expect(notificationService.notifySubscribersBlockFound).toHaveBeenCalled();
+        expect(addressSettings.resetBestDifficultyAndShares).toHaveBeenCalled();
+        expect((client as any).write).lastCalledWith(`{"id":5,"error":null,"result":true}\n`);
+    });
 
 
-});
+
+});

src/models/StratumV1Client.ts

@@ -1,8 +1,7 @@
 import { ConfigService } from '@nestjs/config';
-import Big from 'big.js';
 import * as bitcoinjs from 'bitcoinjs-lib';
 import { plainToInstance } from 'class-transformer';
-import { validate, ValidatorOptions } from 'class-validator';
+import { validate, ValidationError, ValidatorOptions } from 'class-validator';
 import * as crypto from 'crypto';
 import { Socket } from 'net';
 import { firstValueFrom, Subscription } from 'rxjs';
@@ -25,18 +24,24 @@ import { ConfigurationMessage } from './stratum-messages/ConfigurationMessage';
 import { MiningSubmitMessage } from './stratum-messages/MiningSubmitMessage';
 import { StratumErrorMessage } from './stratum-messages/StratumErrorMessage';
 import { SubscriptionMessage } from './stratum-messages/SubscriptionMessage';
+import { EXTRANONCE1_SIZE_BYTES } from './stratum.constants';
 import { SuggestDifficulty } from './stratum-messages/SuggestDifficultyMessage';
 import { StratumV1ClientStatistics } from './StratumV1ClientStatistics';
 
+const TRUE_DIFF_ONE = 2.695953529101131e67;
+const BLOCKED_USER_AGENT_LOG_INTERVAL_MS = 60 * 1000;
+const VALIDATION_ERROR_LOG_INTERVAL_MS = 60 * 1000;
 
 export class StratumV1Client {
+    private static blockedUserAgentLogState = new Map<string, { nextLogAt: number, suppressed: number }>();
+    private static validationErrorLogState = new Map<string, { nextLogAt: number, suppressed: number, sample: string }>();
 
     public clientSubscription: SubscriptionMessage;
     private clientConfiguration: ConfigurationMessage;
     private clientAuthorization: AuthorizationMessage;
     private clientSuggestedDifficulty: SuggestDifficulty;
     private stratumSubscription: Subscription;
-    private backgroundWork: NodeJS.Timer[] = [];
+    private backgroundWork: NodeJS.Timeout[] = [];
 
     private statistics: StratumV1ClientStatistics;
     private stratumInitialized = false;
@@ -52,6 +57,8 @@ export class StratumV1Client {
     //public hashRate: number = 0;
 
     private buffer: string = '';
+    private connectionClosed = false;
+    private lastSentMiningJobTimestamp: number = null;
 
     private miningSubmissionHashes = new Set<string>()
 
@@ -72,16 +79,19 @@ export class StratumV1Client {
             let lines = this.buffer.split('\n');
             this.buffer = lines.pop() || ''; // Save the last part of the data (incomplete line) to the buffer
 
-            lines
-                .filter(m => m.length > 0)
-                .forEach(async (m) => {
+            (async () => {
+                for (const m of lines.filter(l => l.length > 0)) {
+                    if (this.connectionClosed || this.socket.destroyed || this.socket.writableEnded) {
+                        break;
+                    }
                     try {
                         await this.handleMessage(m);
                     } catch (e) {
                         await this.socket.end();
                         console.error(e);
                     }
-                });
+                }
+            })();
         });
 
 
@@ -103,10 +113,8 @@ export class StratumV1Client {
     }
 
     private getRandomHexString() {
-        const randomBytes = crypto.randomBytes(4); // 4 bytes = 32 bits
-        const randomNumber = randomBytes.readUInt32BE(0); // Convert bytes to a 32-bit unsigned integer
-        const hexString = randomNumber.toString(16).padStart(8, '0'); // Convert to hex and pad with zeros
-        return hexString;
+        const randomBytes = crypto.randomBytes(EXTRANONCE1_SIZE_BYTES);
+        return randomBytes.toString('hex');
     }
 
 
@@ -140,6 +148,11 @@ export class StratumV1Client {
                 const errors = await validate(subscriptionMessage, validatorOptions);
 
                 if (errors.length === 0) {
+                    if (this.isBlockedUserAgent(subscriptionMessage.userAgent)) {
+                        this.logBlockedUserAgent(subscriptionMessage.userAgent);
+                        this.closeSocket();
+                        return;
+                    }
 
                     if (this.sessionStart == null) {
                         this.sessionStart = new Date();
@@ -318,17 +331,18 @@ export class StratumV1Client {
 
 
                 } else {
-                    console.log('Mining Submit validation error');
+                    this.logValidationError('Mining Submit validation error', errors);
                     const err = new StratumErrorMessage(
                         miningSubmitMessage.id,
                         eStratumErrorCode.OtherUnknown,
                         'Mining Submit validation error',
                         errors).response();
-                    console.error(err);
                     const success = await this.write(err);
                     if (!success) {
                         return;
                     }
+                    this.closeSocket();
+                    return;
                 }
                 break;
             }
@@ -353,9 +367,9 @@ export class StratumV1Client {
     private async initStratum() {
         this.stratumInitialized = true;
 
-        if (this.validateHeaderCompliance(this.clientSubscription.userAgent)) {
-            console.log(`Non compliant connection from userAgent: ${this.clientSubscription.userAgent}`);
-            await this.socket.end();
+        if (this.isBlockedUserAgent(this.clientSubscription.userAgent)) {
+            this.logBlockedUserAgent(this.clientSubscription.userAgent);
+            this.closeSocket();
             return;
         }
 
@@ -454,6 +468,7 @@ export class StratumV1Client {
         if (!success) {
             return;
         }
+        this.lastSentMiningJobTimestamp = jobTemplate.block.timestamp;
 
 
         //console.log(`Sent new job to ${this.clientAuthorization.worker}.${this.extraNonceAndSessionId}. (clearJobs: ${jobTemplate.blockData.clearJobs}, fee?: ${!this.noFee})`)
@@ -461,46 +476,28 @@ export class StratumV1Client {
     }
 
 
-    private async handleMiningSubmission(submission: MiningSubmitMessage) {
+    private async ensureClientEntity() {
+        if (this.clientEntity != null) {
+            return;
+        }
 
-        if (this.clientEntity == null) {
-            if (this.creatingEntity == null) {
-                this.creatingEntity = new Promise(async (resolve, reject) => {
-                    try {
-                        this.clientEntity = await this.clientService.insert({
-                            sessionId: this.extraNonceAndSessionId,
-                            address: this.clientAuthorization.address,
-                            clientName: this.clientAuthorization.worker,
-                            userAgent: this.clientSubscription.userAgent,
-                            startTime: new Date(),
-                            bestDifficulty: 0
-                        });
-                    } catch (e) {
-                        reject(e);
-                    }
-                    resolve();
+        if (this.creatingEntity == null) {
+            this.creatingEntity = (async () => {
+                this.clientEntity = await this.clientService.insert({
+                    sessionId: this.extraNonceAndSessionId,
+                    address: this.clientAuthorization.address,
+                    clientName: this.clientAuthorization.worker,
+                    userAgent: this.clientSubscription.userAgent,
+                    startTime: new Date(),
+                    bestDifficulty: 0
                 });
-                await this.creatingEntity;
-
-            } else {
-                await this.creatingEntity;
-            }
+            })();
         }
 
-        const submissionHash = submission.hash();
-        if(this.miningSubmissionHashes.has(submissionHash)){
-            const err = new StratumErrorMessage(
-                submission.id,
-                eStratumErrorCode.DuplicateShare,
-                'Duplicate share').response();
-            const success = await this.write(err);
-            if (!success) {
-                return false;
-            }
-            return false;
-        }else{
-            this.miningSubmissionHashes.add(submissionHash);
-        }
+        await this.creatingEntity;
+    }
+
+    private async handleMiningSubmission(submission: MiningSubmitMessage) {
 
         const job = this.stratumV1JobsService.getJobById(submission.jobId);
 
@@ -532,26 +529,61 @@ export class StratumV1Client {
             }
             return false;
         }
-        
 
-        const updatedJobBlock = job.copyAndUpdateBlock(
+        const submissionHash = [
+            submission.jobId,
+            submission.extraNonce2,
+            submission.ntime,
+            submission.nonce,
+            submission.versionMask ?? ''
+        ].join(':');
+        if (this.miningSubmissionHashes.has(submissionHash)) {
+            const err = new StratumErrorMessage(
+                submission.id,
+                eStratumErrorCode.DuplicateShare,
+                'Duplicate share').response();
+            const success = await this.write(err);
+            if (!success) {
+                return false;
+            }
+            return false;
+        } else {
+            this.miningSubmissionHashes.add(submissionHash);
+        }
+
+        const versionMask = parseInt(submission.versionMask, 16);
+        const nonce = parseInt(submission.nonce, 16);
+        const timestamp = parseInt(submission.ntime, 16);
+
+        const header = job.buildHeaderBuffer(
             jobTemplate,
-            parseInt(submission.versionMask, 16),
-            parseInt(submission.nonce, 16),
+            versionMask,
+            nonce,
             this.extraNonceAndSessionId,
             submission.extraNonce2,
-            parseInt(submission.ntime, 16)
+            timestamp
         );
-        const header = updatedJobBlock.toBuffer(true);
         const { submissionDifficulty } = this.calculateDifficulty(header);
 
         //console.log(`DIFF: ${submissionDifficulty} of ${this.sessionDifficulty} from ${this.clientAuthorization.worker + '.' + this.extraNonceAndSessionId}`);
 
 
         if (submissionDifficulty >= this.sessionDifficulty) {
+            const success = await this.write(JSON.stringify(submission.response()) + '\n');
+            if (!success) {
+                return false;
+            }
 
             if (submissionDifficulty >= jobTemplate.blockData.networkDifficulty) {
                 console.log('!!! BLOCK FOUND !!!');
+                const updatedJobBlock = job.copyAndUpdateBlock(
+                    jobTemplate,
+                    versionMask,
+                    nonce,
+                    this.extraNonceAndSessionId,
+                    submission.extraNonce2,
+                    timestamp
+                );
                 const blockHex = updatedJobBlock.toHex(false);
                 const result = await this.bitcoinRpcService.SUBMIT_BLOCK(blockHex);
                 await this.blocksService.save({
@@ -568,12 +600,13 @@ export class StratumV1Client {
                     await this.addressSettingsService.resetBestDifficultyAndShares();
                 }
             }
+            await this.ensureClientEntity();
             try {
                 await this.statistics.addShares(this.clientEntity, this.sessionDifficulty);
                 const now = new Date();
                 // only update every minute
                 //if (this.clientEntity.updatedAt == null || now.getTime() - this.clientEntity.updatedAt.getTime() > 1000 * 60) {
-                await this.clientService.heartbeatBulkAsync(this.clientEntity.id, this.statistics.hashRate, now);
+                this.clientService.heartbeatBulkAsync(this.clientEntity.id, this.statistics.hashRate, now);
                 this.clientEntity.updatedAt = now;
                 //}
 
@@ -582,11 +615,9 @@ export class StratumV1Client {
             }
 
             if (submissionDifficulty > this.clientEntity.bestDifficulty) {
-                await this.clientService.updateBestDifficulty(this.clientEntity.id, submissionDifficulty);
+                await this.clientService.updateBestDifficultyIfHigher(this.clientEntity.id, submissionDifficulty);
                 this.clientEntity.bestDifficulty = submissionDifficulty;
-                if (submissionDifficulty > (await this.addressSettingsService.getSettings(this.clientAuthorization.address, true)).bestDifficulty) {
-                    await this.addressSettingsService.updateBestDifficulty(this.clientAuthorization.address, submissionDifficulty, this.clientEntity.userAgent);
-                }
+                await this.addressSettingsService.updateBestDifficultyIfHigher(this.clientAuthorization.address, submissionDifficulty, this.clientEntity.userAgent);
             }
 
 
@@ -606,7 +637,7 @@ export class StratumV1Client {
         }
 
         //await this.checkDifficulty();
-        return true;
+        return false;
 
     }
 
@@ -630,9 +661,21 @@ export class StratumV1Client {
             await this.socket.write(data);
 
             const jobTemplate = await firstValueFrom(this.stratumV1JobsService.newMiningJob$);
-            // we need to clear the jobs so that the difficulty set takes effect. Otherwise the different miner implementations can cause issues
-            jobTemplate.blockData.clearJobs = true;
-            await this.sendNewMiningJob(jobTemplate);
+            const nextTimestamp = Math.max(
+                jobTemplate.block.timestamp,
+                Math.floor(Date.now() / 1000),
+                (this.lastSentMiningJobTimestamp ?? 0) + 1
+            );
+            // We need to clear jobs so the difficulty takes effect, but avoid mutating or
+            // re-sending the shared cached template with byte-identical work.
+            const refreshedJobTemplate: IJobTemplate = {
+                ...jobTemplate,
+                block: Object.assign(new bitcoinjs.Block(), jobTemplate.block, {
+                    timestamp: nextTimestamp
+                }),
+                blockData: { ...jobTemplate.blockData, clearJobs: true }
+            };
+            await this.sendNewMiningJob(refreshedJobTemplate);
 
         }
     }
@@ -641,34 +684,105 @@ export class StratumV1Client {
 
         const hashResult = bitcoinjs.crypto.hash256(header);
 
-        let s64 = this.le256todouble(hashResult);
-
-        const truediffone = Big('26959535291011309493156476344723991336010898738574164086137773096960');
-        const difficulty = truediffone.div(s64.toString());
-        return { submissionDifficulty: difficulty.toNumber(), submissionHash: hashResult.toString('hex') };
+        const target = this.le256todouble(hashResult);
+        const submissionDifficulty = target === 0 ? Number.POSITIVE_INFINITY : TRUE_DIFF_ONE / target;
+        return { submissionDifficulty, submissionHash: hashResult.toString('hex') };
     }
 
 
-    private le256todouble(target: Buffer): bigint {
+    private le256todouble(target: Buffer): number {
 
-        const number = target.reduceRight((acc, byte) => {
-            // Shift the number 8 bits to the left and OR with the current byte
-            return (acc << BigInt(8)) | BigInt(byte);
-        }, BigInt(0));
+        let number = 0;
+        for (let i = target.length - 1; i >= 0; i--) {
+            number = number * 256 + target[i];
+        }
 
         return number;
     }
 
-    private validateHeaderCompliance(userAgent: string): boolean {
-        const headerCompliance = this.configService.get<string>('COMPLIANT_HEADERS');
-        if (!headerCompliance || headerCompliance.trim() === '') {
+    private isBlockedUserAgent(userAgent: string): boolean {
+        const blockedUserAgents = this.configService.get<string>('NON_COMPLIANT_USER_AGENTS')
+            || this.configService.get<string>('BLOCKED_USER_AGENTS')
+            || this.configService.get<string>('COMPLIANT_HEADERS');
+        if (!blockedUserAgents || blockedUserAgents.trim() === '') {
             return false;
         }
 
-        const complianceList = headerCompliance.split(',').map(ua => ua.trim().toLowerCase());
+        const blockedList = blockedUserAgents.split(',').map(ua => ua.trim().toLowerCase());
         const userAgentLower = userAgent.toLowerCase();
 
-        return complianceList.some(compliant => compliant.length > 0 && userAgentLower.includes(compliant));
+        return blockedList.some(blocked => blocked.length > 0 && userAgentLower.includes(blocked));
+    }
+
+    private logBlockedUserAgent(userAgent: string) {
+        const now = Date.now();
+        const logState = StratumV1Client.blockedUserAgentLogState.get(userAgent);
+
+        if (logState != null && now < logState.nextLogAt) {
+            logState.suppressed += 1;
+            return;
+        }
+
+        const suppressed = logState?.suppressed ?? 0;
+        const suffix = suppressed > 0 ? ` (${suppressed} similar connections suppressed)` : '';
+        console.log(`Blocked non-compliant connection from userAgent: ${userAgent}${suffix}`);
+        StratumV1Client.blockedUserAgentLogState.set(userAgent, {
+            nextLogAt: now + BLOCKED_USER_AGENT_LOG_INTERVAL_MS,
+            suppressed: 0
+        });
+    }
+
+    private logValidationError(label: string, errors: ValidationError[]) {
+        const now = Date.now();
+        const signature = this.getValidationErrorSignature(errors);
+        const sample = this.getValidationErrorSample(errors);
+        const key = `${label}:${signature}`;
+        const logState = StratumV1Client.validationErrorLogState.get(key);
+
+        if (logState != null && now < logState.nextLogAt) {
+            logState.suppressed += 1;
+            return;
+        }
+
+        const suppressed = logState?.suppressed ?? 0;
+        const suffix = suppressed > 0 ? ` (${suppressed} similar validation errors suppressed)` : '';
+        console.warn(`${label}: ${signature}${sample}${suffix}`);
+        StratumV1Client.validationErrorLogState.set(key, {
+            nextLogAt: now + VALIDATION_ERROR_LOG_INTERVAL_MS,
+            suppressed: 0,
+            sample
+        });
+    }
+
+    private getValidationErrorSignature(errors: ValidationError[]): string {
+        if (errors.length === 0) {
+            return 'unknown';
+        }
+
+        return errors.map(error => {
+            const constraints = Object.keys(error.constraints ?? {}).sort().join('|') || 'invalid';
+            return `${error.property}:${constraints}`;
+        }).join(';');
+    }
+
+    private getValidationErrorSample(errors: ValidationError[]): string {
+        const values = errors
+            .map(error => error.value)
+            .filter(value => value != null)
+            .map(value => String(value).replace(/[\r\n]/g, '').slice(0, 64));
+
+        if (values.length === 0) {
+            return '';
+        }
+
+        return ` sample=${values.join(',')}`;
+    }
+
+    private closeSocket() {
+        this.connectionClosed = true;
+        if (!this.socket.destroyed) {
+            this.socket.destroy();
+        }
     }
 
     private async write(message: string): Promise<boolean> {

src/models/StratumV1ClientStatistics.spec.ts

@@ -0,0 +1,107 @@
+import { StratumV1ClientStatistics } from './StratumV1ClientStatistics';
+
+describe('StratumV1ClientStatistics', () => {
+    const client = {
+        id: 'client-id',
+        address: 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4',
+        clientName: 'bitaxe3',
+        sessionId: '57a6f098'
+    } as any;
+
+    let clientStatisticsService: {
+        insert: jest.Mock,
+        updateBulkAsync: jest.Mock
+    };
+    let statistics: StratumV1ClientStatistics;
+
+    beforeEach(() => {
+        jest.useFakeTimers();
+        jest.setSystemTime(new Date('2026-05-06T12:00:00Z'));
+        clientStatisticsService = {
+            insert: jest.fn().mockResolvedValue(undefined),
+            updateBulkAsync: jest.fn().mockResolvedValue(undefined)
+        };
+        statistics = new StratumV1ClientStatistics(clientStatisticsService as any);
+    });
+
+    afterEach(() => {
+        jest.useRealTimers();
+    });
+
+    it('should insert the first share bucket', async () => {
+        await statistics.addShares(client, 64);
+
+        expect(clientStatisticsService.insert).toHaveBeenCalledWith({
+            time: new Date('2026-05-06T12:00:00Z').getTime(),
+            clientId: client.id,
+            shares: 64,
+            acceptedCount: 1,
+            address: client.address,
+            clientName: client.clientName,
+            sessionId: client.sessionId
+        });
+    });
+
+    it('should update the current share bucket for additional shares', async () => {
+        await statistics.addShares(client, 64);
+        await statistics.addShares(client, 32);
+
+        expect(clientStatisticsService.updateBulkAsync).toHaveBeenCalledWith({
+            time: new Date('2026-05-06T12:00:00Z').getTime(),
+            clientId: client.id,
+            shares: 96,
+            acceptedCount: 2
+        });
+    });
+
+    it('should create a new share bucket when the time slot changes', async () => {
+        await statistics.addShares(client, 64);
+        jest.setSystemTime(new Date('2026-05-06T12:10:00Z'));
+
+        await statistics.addShares(client, 32);
+
+        expect(clientStatisticsService.updateBulkAsync).toHaveBeenCalledWith({
+            time: new Date('2026-05-06T12:00:00Z').getTime(),
+            clientId: client.id,
+            shares: 64,
+            acceptedCount: 1
+        });
+        expect(clientStatisticsService.insert).toHaveBeenLastCalledWith({
+            time: new Date('2026-05-06T12:10:00Z').getTime(),
+            clientId: client.id,
+            shares: 32,
+            acceptedCount: 1,
+            address: client.address,
+            clientName: client.clientName,
+            sessionId: client.sessionId
+        });
+    });
+
+    it('should not suggest a difficulty change before enough time or shares have passed', () => {
+        expect(statistics.getSuggestedDifficulty(64)).toBeNull();
+    });
+
+    it('should lower difficulty when a miner has not submitted shares for several minutes', () => {
+        jest.setSystemTime(new Date('2026-05-06T12:06:00Z'));
+
+        expect(statistics.getSuggestedDifficulty(64)).toBe(8);
+    });
+
+    it('should increase difficulty for rapid submissions', async () => {
+        for (let i = 0; i < 5; i++) {
+            jest.setSystemTime(new Date(Date.parse('2026-05-06T12:00:00Z') + (i * 1000)));
+            await statistics.addShares(client, 64);
+        }
+
+        expect(statistics.getSuggestedDifficulty(64)).toBe(2048);
+    });
+
+    it('should decrease difficulty for slow submissions', async () => {
+        for (let i = 0; i < 5; i++) {
+            jest.setSystemTime(new Date(Date.parse('2026-05-06T12:00:00Z') + (i * 150000)));
+            await statistics.addShares(client, 64);
+        }
+
+        expect(statistics.getSuggestedDifficulty(128)).toBe(16);
+    });
+});

src/models/StratumV2Client.spec.ts

@@ -0,0 +1,206 @@
+import { ConfigService } from '@nestjs/config';
+import { Socket } from 'net';
+import { BehaviorSubject, firstValueFrom } from 'rxjs';
+
+import { MockRecording1 } from '../../test/models/MockRecording1';
+import { ClientEntity } from '../ORM/client/client.entity';
+import { StratumV1JobsService } from '../services/stratum-v1-jobs.service';
+import { BufferReader } from './sv2/sv2-binary-codec';
+import { SV2_CHANNEL_MSG_FLAG, Sv2MsgType } from './sv2/sv2-constants';
+import {
+    deserializeOpenExtendedMiningChannelSuccess,
+    deserializeNewExtendedMiningJob,
+    serializeOpenExtendedMiningChannel,
+    serializeSubmitSharesExtended,
+} from './sv2/sv2-extended-messages';
+import { deserializeSetNewPrevHash, deserializeSubmitSharesError } from './sv2/sv2-messages';
+import { StratumV2Client } from './StratumV2Client';
+
+describe('StratumV2Client extended channels', () => {
+    let consoleLogSpy: jest.SpyInstance;
+    let consoleWarnSpy: jest.SpyInstance;
+    let consoleErrorSpy: jest.SpyInstance;
+
+    beforeEach(() => {
+        jest.useFakeTimers();
+        jest.setSystemTime(new Date(parseInt(MockRecording1.TIME, 16) * 1000));
+        consoleLogSpy = jest.spyOn(console, 'log').mockImplementation(() => undefined);
+        consoleWarnSpy = jest.spyOn(console, 'warn').mockImplementation(() => undefined);
+        consoleErrorSpy = jest.spyOn(console, 'error').mockImplementation(() => undefined);
+    });
+
+    afterEach(() => {
+        consoleLogSpy.mockRestore();
+        consoleWarnSpy.mockRestore();
+        consoleErrorSpy.mockRestore();
+        jest.useRealTimers();
+    });
+
+    it('opens an extended channel and sends initial extended work', async () => {
+        const { client, sentFrames } = await createClient();
+        const maxTarget = Buffer.alloc(32, 0xff);
+
+        await (client as any).handleOpenExtendedMiningChannel(serializeOpenExtendedMiningChannel({
+            requestId: 7,
+            userIdentity: 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.worker',
+            nominalHashRate: 0,
+            maxTarget,
+            minExtranonceSize: 8,
+        }));
+
+        const successFrame = sentFrames.find(frame => frame.msgType === Sv2MsgType.OPEN_EXTENDED_MINING_CHANNEL_SUCCESS);
+        const jobFrames = sentFrames.filter(frame => frame.msgType === Sv2MsgType.NEW_EXTENDED_MINING_JOB);
+        const jobFrame = jobFrames[jobFrames.length - 1];
+        const prevHashFrames = sentFrames.filter(frame => frame.msgType === Sv2MsgType.SET_NEW_PREV_HASH);
+        const prevHashFrame = prevHashFrames[prevHashFrames.length - 1];
+
+        expect(successFrame?.extensionType).toBe(0);
+        const success = deserializeOpenExtendedMiningChannelSuccess(new BufferReader(successFrame.payload));
+        expect(success.requestId).toBe(7);
+        expect(success.channelId).toBe(1);
+        expect(success.extranonceSize).toBe(8);
+        expect(success.extranoncePrefix).toEqual(Buffer.from('00000001', 'hex'));
+
+        expect(jobFrame?.extensionType).toBe(SV2_CHANNEL_MSG_FLAG);
+        const job = deserializeNewExtendedMiningJob(new BufferReader(jobFrame.payload));
+        expect(job.channelId).toBe(1);
+        expect(job.minNtime).toBeNull();
+        expect(job.coinbasePrefix.length).toBeGreaterThan(0);
+        expect(job.coinbaseSuffix.length).toBeGreaterThan(0);
+        expect(job.merklePath.length).toBeGreaterThan(0);
+
+        expect(prevHashFrame?.extensionType).toBe(SV2_CHANNEL_MSG_FLAG);
+        const prevHash = deserializeSetNewPrevHash(new BufferReader(prevHashFrame.payload));
+        expect(prevHash.channelId).toBe(1);
+        expect(prevHash.jobId).toBe(job.jobId);
+    });
+
+    it('rejects extended shares with the wrong negotiated extranonce size', async () => {
+        const { client, sentFrames } = await createClient();
+        await (client as any).handleOpenExtendedMiningChannel(serializeOpenExtendedMiningChannel({
+            requestId: 1,
+            userIdentity: 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.worker',
+            nominalHashRate: 0,
+            maxTarget: Buffer.alloc(32, 0xff),
+            minExtranonceSize: 8,
+        }));
+        const jobFrames = sentFrames.filter(frame => frame.msgType === Sv2MsgType.NEW_EXTENDED_MINING_JOB);
+        const jobFrame = jobFrames[jobFrames.length - 1];
+        const job = deserializeNewExtendedMiningJob(new BufferReader(jobFrame.payload));
+        sentFrames.length = 0;
+
+        await (client as any).handleSubmitSharesExtended(serializeSubmitSharesExtended({
+            channelId: 1,
+            sequenceNumber: 42,
+            jobId: job.jobId,
+            nonce: 0,
+            ntime: parseInt(MockRecording1.TIME, 16),
+            version: job.version,
+            extranonce: Buffer.alloc(7),
+        }));
+
+        const errorFrame = sentFrames.find(frame => frame.msgType === Sv2MsgType.SUBMIT_SHARES_ERROR);
+        expect(errorFrame?.extensionType).toBe(SV2_CHANNEL_MSG_FLAG);
+        const error = deserializeSubmitSharesError(new BufferReader(errorFrame.payload));
+        expect(error.channelId).toBe(1);
+        expect(error.sequenceNumber).toBe(42);
+        expect(error.errorCode).toBe('invalid-extranonce-size');
+    });
+
+    async function createClient(): Promise<{ client: StratumV2Client; sentFrames: any[] }> {
+        const blockTemplate$ = new BehaviorSubject(MockRecording1.BLOCK_TEMPLATE);
+        const bitcoinRpcService = {
+            newBlockTemplate$: blockTemplate$.asObservable(),
+            miningInfo: { blocks: MockRecording1.BLOCK_TEMPLATE.height },
+            SUBMIT_BLOCK: jest.fn().mockResolvedValue(null),
+        };
+        const stratumV1JobsService = new StratumV1JobsService(bitcoinRpcService as any);
+        await firstValueFrom(stratumV1JobsService.newMiningJob$);
+
+        const mockSocket: any = {
+            destroyed: false,
+            writableEnded: false,
+            on: jest.fn().mockReturnThis(),
+            write: jest.fn((data, callback) => {
+                callback?.();
+                return true;
+            }),
+            destroy: jest.fn(function destroy() {
+                mockSocket.destroyed = true;
+                return mockSocket;
+            }),
+        };
+        const socket = mockSocket as Socket;
+
+        const clientEntity = {
+            id: 1,
+            sessionId: 'sv2-session',
+            address: 'tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4',
+            clientName: 'worker',
+            userAgent: 'test/sv2',
+            bestDifficulty: 0,
+        } as unknown as ClientEntity;
+
+        let nextChannelId = 1;
+        const sentFrames: any[] = [];
+        const client = new StratumV2Client(
+            socket,
+            Buffer.alloc(0),
+            {
+                getNoiseConfig: () => ({
+                    staticKeypair: {
+                        privateKey: Buffer.alloc(32, 1),
+                        publicKey: Buffer.alloc(64, 2),
+                    },
+                    certificateMessage: {
+                        version: 0,
+                        validFrom: 0,
+                        notValidAfter: 1,
+                        signature: Buffer.alloc(64),
+                    },
+                }),
+                getNextChannelId: () => nextChannelId++,
+                generateExtranoncePrefix: () => Buffer.from('00000002', 'hex'),
+                allocateExtendedExtranoncePrefix: jest.fn(() => Buffer.from('00000001', 'hex')),
+                releaseExtendedExtranoncePrefix: jest.fn(),
+                getExtendedMinerExtranonceSize: () => 8,
+            } as any,
+            stratumV1JobsService,
+            bitcoinRpcService as any,
+            {
+                insert: jest.fn().mockResolvedValue(clientEntity),
+                delete: jest.fn().mockResolvedValue(undefined),
+                heartbeatBulkAsync: jest.fn(),
+                updateBestDifficultyIfHigher: jest.fn().mockResolvedValue(undefined),
+            } as any,
+            {
+                insert: jest.fn().mockResolvedValue(undefined),
+                updateBulkAsync: jest.fn(),
+            } as any,
+            { notifySubscribersBlockFound: jest.fn().mockResolvedValue(undefined) } as any,
+            { save: jest.fn().mockResolvedValue(undefined) } as any,
+            {
+                get: jest.fn((key: string) => {
+                    switch (key) {
+                        case 'NETWORK':
+                            return 'testnet';
+                        case 'SV2_START_DIFFICULTY':
+                            return '1';
+                        default:
+                            return null;
+                    }
+                }),
+            } as unknown as ConfigService,
+            {
+                resetBestDifficultyAndShares: jest.fn().mockResolvedValue(undefined),
+                updateBestDifficultyIfHigher: jest.fn().mockResolvedValue(undefined),
+            } as any,
+        );
+        (client as any).sendFrame = jest.fn((msgType: number, payload: Buffer, extensionType = 0) => {
+            sentFrames.push({ msgType, payload, extensionType });
+            return Promise.resolve();
+        });
+
+        return { client, sentFrames };
+    }
+});

src/models/stratum-messages/AuthorizationMessage.spec.ts

@@ -0,0 +1,40 @@
+import { plainToInstance } from 'class-transformer';
+
+import { AuthorizationMessage } from './AuthorizationMessage';
+
+describe('AuthorizationMessage', () => {
+    it('should parse address, worker, and starting difficulty', () => {
+        const message = plainToInstance(
+            AuthorizationMessage,
+            JSON.parse('{"id":3,"method":"mining.authorize","params":["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.worker1","x,d=2048"]}')
+        );
+
+        expect(message.address).toBe('tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4');
+        expect(message.worker).toBe('worker1');
+        expect(message.password).toBe('x,d=2048');
+        expect(message.startingDiff).toBe(2048);
+    });
+
+    it('should default worker name when one is not provided', () => {
+        const message = plainToInstance(
+            AuthorizationMessage,
+            JSON.parse('{"id":3,"method":"mining.authorize","params":["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4","x"]}')
+        );
+
+        expect(message.worker).toBe('worker');
+        expect(message.startingDiff).toBeNull();
+    });
+
+    it('should build successful authorization responses', () => {
+        const message = plainToInstance(
+            AuthorizationMessage,
+            JSON.parse('{"id":3,"method":"mining.authorize","params":["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.worker1","x"]}')
+        );
+
+        expect(message.response()).toEqual({
+            id: 3,
+            error: null,
+            result: true
+        });
+    });
+});

src/models/stratum-messages/MiningSubmitMessage.spec.ts

@@ -1,4 +1,5 @@
 import { plainToInstance } from 'class-transformer';
+import { validate } from 'class-validator';
 
 import { MiningSubmitMessage } from './MiningSubmitMessage';
 
@@ -13,7 +14,7 @@ describe('MiningSubmitMessage', () => {
 
     describe('test message parsing', () => {
 
-        const MINING_SUBMIT_MESSAGE = ' {"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "99020000", "64b1f10f", "2402812d", "00006000"]}'
+        const MINING_SUBMIT_MESSAGE = ' {"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "9902000000000000", "64b1f10f", "2402812d", "00006000"]}'
 
         const message = plainToInstance(
             MiningSubmitMessage,
@@ -24,11 +25,39 @@ describe('MiningSubmitMessage', () => {
             expect(message.id).toEqual(5);
             expect(message.userId).toEqual('tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3');
             expect(message.jobId).toEqual('1');
-            expect(message.extraNonce2).toEqual('99020000');
+            expect(message.extraNonce2).toEqual('9902000000000000');
             expect(message.ntime).toEqual('64b1f10f');
             expect(message.nonce).toEqual('2402812d');
             expect(message.versionMask).toEqual('00006000');
         });
+
+        it('should validate 8-byte extranonce2 submissions', async () => {
+            const errors = await validate(message);
+
+            expect(errors).toEqual([]);
+        });
+
+        it('should reject short extranonce2 submissions', async () => {
+            const shortMessage = plainToInstance(
+                MiningSubmitMessage,
+                JSON.parse(' {"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "99020000", "64b1f10f", "2402812d", "00006000"]}'),
+            );
+
+            const errors = await validate(shortMessage);
+
+            expect(errors.some(error => error.property === 'extraNonce2')).toBe(true);
+        });
+
+        it('should reject long extranonce2 submissions', async () => {
+            const longMessage = plainToInstance(
+                MiningSubmitMessage,
+                JSON.parse(' {"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "990200000000000000", "64b1f10f", "2402812d", "00006000"]}'),
+            );
+
+            const errors = await validate(longMessage);
+
+            expect(errors.some(error => error.property === 'extraNonce2')).toBe(true);
+        });
     });
 
 

src/models/stratum-messages/MiningSubmitMessage.ts

@@ -1,7 +1,8 @@
 import { Expose, Transform } from 'class-transformer';
-import { ArrayMaxSize, ArrayMinSize, IsArray, IsString } from 'class-validator';
+import { ArrayMaxSize, ArrayMinSize, IsArray, IsString, Length } from 'class-validator';
 
 import { eRequestMethod } from '../enums/eRequestMethod';
+import { EXTRANONCE2_SIZE_BYTES } from '../stratum.constants';
 import { StratumBaseMessage } from './StratumBaseMessage';
 import * as bitcoinjs from 'bitcoinjs-lib';
 
@@ -27,6 +28,7 @@ export class MiningSubmitMessage extends StratumBaseMessage {
     public jobId: string;
     @Expose()
     @IsString()
+    @Length(EXTRANONCE2_SIZE_BYTES * 2, EXTRANONCE2_SIZE_BYTES * 2)
     @Transform(({ value, key, obj, type }) => {
         return obj.params[2];
     })
@@ -75,4 +77,4 @@ export class MiningSubmitMessage extends StratumBaseMessage {
 
 
 
-}
+}

src/models/stratum-messages/SubscriptionMessage.spec.ts

@@ -0,0 +1,45 @@
+import { plainToInstance } from 'class-transformer';
+
+import { SubscriptionMessage } from './SubscriptionMessage';
+
+describe('SubscriptionMessage', () => {
+    it('should parse and refine known user agents', () => {
+        const bosminer = plainToInstance(
+            SubscriptionMessage,
+            JSON.parse('{"id":1,"method":"mining.subscribe","params":["bosminer/23.08"]}')
+        );
+        const cpuminer = plainToInstance(
+            SubscriptionMessage,
+            JSON.parse('{"id":1,"method":"mining.subscribe","params":["cpuminer-opt/1.0"]}')
+        );
+
+        expect(bosminer.userAgent).toBe('Braiins OS');
+        expect(cpuminer.userAgent).toBe('cpuminer');
+    });
+
+    it('should default missing user agents to unknown', () => {
+        const message = plainToInstance(
+            SubscriptionMessage,
+            JSON.parse('{"id":1,"method":"mining.subscribe","params":[]}')
+        );
+
+        expect(message.userAgent).toBe('unknown');
+    });
+
+    it('should respond with extranonce2 size of 8 bytes', () => {
+        const message = plainToInstance(
+            SubscriptionMessage,
+            JSON.parse('{"id":1,"method":"mining.subscribe","params":["bitaxe v2.2"]}')
+        );
+
+        expect(message.response('57a6f098')).toEqual({
+            id: 1,
+            error: null,
+            result: [
+                [['mining.notify', '57a6f098']],
+                '57a6f098',
+                8
+            ]
+        });
+    });
+});

src/models/stratum-messages/SubscriptionMessage.ts

@@ -2,6 +2,7 @@ import { Expose, Transform } from 'class-transformer';
 import { IsArray, IsString, MaxLength } from 'class-validator';
 
 import { eRequestMethod } from '../enums/eRequestMethod';
+import { EXTRANONCE2_SIZE_BYTES } from '../stratum.constants';
 import { StratumBaseMessage } from './StratumBaseMessage';
 
 export class SubscriptionMessage extends StratumBaseMessage {
@@ -32,7 +33,7 @@ export class SubscriptionMessage extends StratumBaseMessage {
                     ['mining.notify', clientId]
                 ],
                 clientId, //Extranonce1 -  Hex-encoded, per-connection unique string which will be used for coinbase serialization later. Keep it safe!
-                4 //Extranonce2_size - Represents expected length of extranonce2 which will be generated by the miner.
+                EXTRANONCE2_SIZE_BYTES //Extranonce2_size - Represents expected length of extranonce2 which will be generated by the miner.
             ]
         }
 
@@ -50,4 +51,4 @@ export class SubscriptionMessage extends StratumBaseMessage {
         }
         return userAgent;
     }
-}
+}

src/models/stratum.constants.ts

@@ -0,0 +1,3 @@
+export const EXTRANONCE1_SIZE_BYTES = 4;
+export const EXTRANONCE2_SIZE_BYTES = 8;
+export const TOTAL_EXTRANONCE_SIZE_BYTES = EXTRANONCE1_SIZE_BYTES + EXTRANONCE2_SIZE_BYTES;

src/models/sv2/sv2-authority-key.spec.ts

@@ -0,0 +1,19 @@
+import { encodeSv2AuthorityPublicKey } from './sv2-authority-key';
+
+describe('SV2 authority key encoding', () => {
+  it('matches the protocol security test vector', () => {
+    const rawPublicKey = Buffer.from([
+      118, 99, 112, 0, 151, 156, 28, 17,
+      175, 12, 48, 11, 205, 140, 127, 228,
+      134, 16, 252, 233, 185, 193, 30, 61,
+      174, 227, 90, 224, 176, 138, 116, 85,
+    ]);
+
+    expect(encodeSv2AuthorityPublicKey(rawPublicKey))
+      .toBe('9bXiEd8boQVhq7WddEcERUL5tyyJVFYdU8th3HfbNXK3Yw6GRXh');
+  });
+
+  it('rejects non-x-only public keys', () => {
+    expect(() => encodeSv2AuthorityPublicKey(Buffer.alloc(33))).toThrow(RangeError);
+  });
+});

src/models/sv2/sv2-authority-key.ts

@@ -0,0 +1,19 @@
+import * as bs58 from 'bs58';
+import * as crypto from 'crypto';
+
+const AUTHORITY_KEY_VERSION_PREFIX = Buffer.from([1, 0]);
+
+export function encodeSv2AuthorityPublicKey(publicKey: Buffer): string {
+  if (publicKey.length !== 32) {
+    throw new RangeError(`SV2 authority public key must be 32 bytes, got ${publicKey.length}`);
+  }
+
+  const versionedKey = Buffer.concat([AUTHORITY_KEY_VERSION_PREFIX, publicKey]);
+  const checksum = crypto
+    .createHash('sha256')
+    .update(crypto.createHash('sha256').update(versionedKey).digest())
+    .digest()
+    .subarray(0, 4);
+
+  return bs58.encode(Buffer.concat([versionedKey, checksum]));
+}

src/models/sv2/sv2-binary-codec.spec.ts

@@ -0,0 +1,249 @@
+import { BufferReader, BufferWriter } from './sv2-binary-codec';
+
+describe('SV2 Binary Codec', () => {
+  // ── Round-trip Tests ────────────────────────────────────────────────
+
+  describe('BufferWriter + BufferReader round-trips', () => {
+    it('should round-trip Bool', () => {
+      const w = new BufferWriter();
+      w.writeBool(true);
+      w.writeBool(false);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readBool()).toBe(true);
+      expect(r.readBool()).toBe(false);
+    });
+
+    it('should round-trip U8', () => {
+      const w = new BufferWriter();
+      w.writeU8(0);
+      w.writeU8(255);
+      w.writeU8(42);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readU8()).toBe(0);
+      expect(r.readU8()).toBe(255);
+      expect(r.readU8()).toBe(42);
+    });
+
+    it('should round-trip U16', () => {
+      const w = new BufferWriter();
+      w.writeU16(0);
+      w.writeU16(65535);
+      w.writeU16(1234);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readU16()).toBe(0);
+      expect(r.readU16()).toBe(65535);
+      expect(r.readU16()).toBe(1234);
+    });
+
+    it('should round-trip U24', () => {
+      const w = new BufferWriter();
+      w.writeU24(0);
+      w.writeU24(0xffffff);
+      w.writeU24(123456);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readU24()).toBe(0);
+      expect(r.readU24()).toBe(0xffffff);
+      expect(r.readU24()).toBe(123456);
+    });
+
+    it('should round-trip U32', () => {
+      const w = new BufferWriter();
+      w.writeU32(0);
+      w.writeU32(0xffffffff);
+      w.writeU32(305419896);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readU32()).toBe(0);
+      expect(r.readU32()).toBe(0xffffffff);
+      expect(r.readU32()).toBe(305419896);
+    });
+
+    it('should round-trip U64', () => {
+      const w = new BufferWriter();
+      w.writeU64(0n);
+      w.writeU64(0xffffffffffffffffn);
+      w.writeU64(123456789012345678n);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readU64()).toBe(0n);
+      expect(r.readU64()).toBe(0xffffffffffffffffn);
+      expect(r.readU64()).toBe(123456789012345678n);
+    });
+
+    it('should round-trip U256', () => {
+      const val = Buffer.alloc(32);
+      for (let i = 0; i < 32; i++) val[i] = i;
+      const w = new BufferWriter();
+      w.writeU256(val);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readU256()).toEqual(val);
+    });
+
+    it('should round-trip F32', () => {
+      const w = new BufferWriter();
+      w.writeF32(3.14);
+      w.writeF32(0);
+      w.writeF32(-1.5);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readF32()).toBeCloseTo(3.14, 2);
+      expect(r.readF32()).toBe(0);
+      expect(r.readF32()).toBe(-1.5);
+    });
+
+    it('should round-trip Str0_255', () => {
+      const w = new BufferWriter();
+      w.writeStr0_255('');
+      w.writeStr0_255('hello');
+      w.writeStr0_255('mining/pool/1.0');
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readStr0_255()).toBe('');
+      expect(r.readStr0_255()).toBe('hello');
+      expect(r.readStr0_255()).toBe('mining/pool/1.0');
+    });
+
+    it('should round-trip B0_32', () => {
+      const val = Buffer.from([1, 2, 3, 4]);
+      const w = new BufferWriter();
+      w.writeB0_32(Buffer.alloc(0));
+      w.writeB0_32(val);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readB0_32()).toEqual(Buffer.alloc(0));
+      expect(r.readB0_32()).toEqual(val);
+    });
+
+    it('should round-trip B0_255', () => {
+      const val = Buffer.alloc(100, 0xab);
+      const w = new BufferWriter();
+      w.writeB0_255(val);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readB0_255()).toEqual(val);
+    });
+
+    it('should round-trip B0_64K', () => {
+      const val = Buffer.alloc(1000, 0xcd);
+      const w = new BufferWriter();
+      w.writeB0_64K(val);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readB0_64K()).toEqual(val);
+    });
+
+    it('should round-trip Seq0_255', () => {
+      const items = [10, 20, 30];
+      const w = new BufferWriter();
+      w.writeSeq0_255(items, (wr, v) => wr.writeU32(v));
+      const r = new BufferReader(w.toBuffer());
+      const result = r.readSeq0_255((rd) => rd.readU32());
+      expect(result).toEqual(items);
+    });
+
+    it('should round-trip Seq0_64K', () => {
+      const items = ['alpha', 'beta'];
+      const w = new BufferWriter();
+      w.writeSeq0_64K(items, (wr, v) => wr.writeStr0_255(v));
+      const r = new BufferReader(w.toBuffer());
+      const result = r.readSeq0_64K((rd) => rd.readStr0_255());
+      expect(result).toEqual(items);
+    });
+  });
+
+  // ── Little-endian Verification ──────────────────────────────────────
+
+  describe('little-endian encoding', () => {
+    it('U16 should be little-endian', () => {
+      const w = new BufferWriter();
+      w.writeU16(0x0102);
+      const buf = w.toBuffer();
+      expect(buf[0]).toBe(0x02); // low byte first
+      expect(buf[1]).toBe(0x01);
+    });
+
+    it('U32 should be little-endian', () => {
+      const w = new BufferWriter();
+      w.writeU32(0x01020304);
+      const buf = w.toBuffer();
+      expect(buf[0]).toBe(0x04);
+      expect(buf[1]).toBe(0x03);
+      expect(buf[2]).toBe(0x02);
+      expect(buf[3]).toBe(0x01);
+    });
+  });
+
+  // ── Bounds Checking ─────────────────────────────────────────────────
+
+  describe('bounds checking', () => {
+    it('BufferReader should throw on underflow', () => {
+      const r = new BufferReader(Buffer.alloc(1));
+      r.readU8(); // consumes the one byte
+      expect(() => r.readU8()).toThrow(RangeError);
+    });
+
+    it('BufferReader should throw when reading U32 from 2-byte buffer', () => {
+      const r = new BufferReader(Buffer.alloc(2));
+      expect(() => r.readU32()).toThrow(RangeError);
+    });
+
+    it('B0_32 should reject payloads > 32 bytes', () => {
+      const w = new BufferWriter();
+      expect(() => w.writeB0_32(Buffer.alloc(33))).toThrow(RangeError);
+    });
+
+    it('B0_32 reader should reject length > 32', () => {
+      // Craft a buffer with length prefix = 33
+      const buf = Buffer.alloc(34);
+      buf[0] = 33;
+      const r = new BufferReader(buf);
+      expect(() => r.readB0_32()).toThrow(RangeError);
+    });
+
+    it('U256 writer should reject non-32-byte buffers', () => {
+      const w = new BufferWriter();
+      expect(() => w.writeU256(Buffer.alloc(31))).toThrow(RangeError);
+    });
+
+    it('Str0_255 should reject strings > 255 bytes', () => {
+      const w = new BufferWriter();
+      expect(() => w.writeStr0_255('a'.repeat(256))).toThrow(RangeError);
+    });
+
+    it('remaining should track consumed bytes', () => {
+      const r = new BufferReader(Buffer.alloc(10));
+      expect(r.remaining).toBe(10);
+      r.readU32();
+      expect(r.remaining).toBe(6);
+      expect(r.position).toBe(4);
+    });
+  });
+
+  // ── Edge Cases ──────────────────────────────────────────────────────
+
+  describe('edge cases', () => {
+    it('empty buffer reader has 0 remaining', () => {
+      const r = new BufferReader(Buffer.alloc(0));
+      expect(r.remaining).toBe(0);
+    });
+
+    it('empty Seq0_255 round-trips', () => {
+      const w = new BufferWriter();
+      w.writeSeq0_255([], (wr, v) => wr.writeU8(v as number));
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readSeq0_255((rd) => rd.readU8())).toEqual([]);
+    });
+
+    it('maximum B0_32 (32 bytes) round-trips', () => {
+      const val = Buffer.alloc(32, 0xff);
+      const w = new BufferWriter();
+      w.writeB0_32(val);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readB0_32()).toEqual(val);
+    });
+
+    it('writeU32 handles signed int32 from bitcoinjs block.version', () => {
+      // bitcoinjs-lib stores block.version as signed Int32 (readInt32).
+      // Version rolling or BIP9 signaling can set bit 31, producing
+      // a negative JS number. writeU32 must handle this via >>> 0.
+      const signedVersion = -1554660091; // 0xA355C505 unsigned
+      const w = new BufferWriter();
+      w.writeU32(signedVersion);
+      const r = new BufferReader(w.toBuffer());
+      expect(r.readU32()).toBe(0xA355C505);
+    });
+  });
+});

src/models/sv2/sv2-binary-codec.ts

@@ -0,0 +1,301 @@
+// ── SV2 Binary Codec ────────────────────────────────────────────────
+// Sequential Buffer reader / accumulator-pattern writer for all SV2
+// data types.  All multi-byte integers are little-endian per spec.
+
+// ── BufferReader ────────────────────────────────────────────────────
+
+export class BufferReader {
+  private offset = 0;
+
+  constructor(private readonly buf: Buffer) {}
+
+  get remaining(): number {
+    return this.buf.length - this.offset;
+  }
+
+  get position(): number {
+    return this.offset;
+  }
+
+  private ensure(n: number): void {
+    if (this.offset + n > this.buf.length) {
+      throw new RangeError(
+        `BufferReader: need ${n} bytes at offset ${this.offset}, only ${this.remaining} available`,
+      );
+    }
+  }
+
+  readBool(): boolean {
+    this.ensure(1);
+    return this.buf[this.offset++] !== 0;
+  }
+
+  readU8(): number {
+    this.ensure(1);
+    return this.buf[this.offset++];
+  }
+
+  readU16(): number {
+    this.ensure(2);
+    const v = this.buf.readUInt16LE(this.offset);
+    this.offset += 2;
+    return v;
+  }
+
+  readU24(): number {
+    this.ensure(3);
+    const v =
+      this.buf[this.offset] |
+      (this.buf[this.offset + 1] << 8) |
+      (this.buf[this.offset + 2] << 16);
+    this.offset += 3;
+    return v;
+  }
+
+  readU32(): number {
+    this.ensure(4);
+    const v = this.buf.readUInt32LE(this.offset);
+    this.offset += 4;
+    return v;
+  }
+
+  /** Read Sv2Option<u32>: 1-byte flag (0=None, 1=Some) + optional 4-byte u32 LE */
+  readOptionU32(): number | null {
+    this.ensure(1);
+    const flag = this.buf[this.offset++];
+    if (flag === 0) return null;
+    this.ensure(4);
+    const v = this.buf.readUInt32LE(this.offset);
+    this.offset += 4;
+    return v;
+  }
+
+  readU64(): bigint {
+    this.ensure(8);
+    const v = this.buf.readBigUInt64LE(this.offset);
+    this.offset += 8;
+    return v;
+  }
+
+  readU256(): Buffer {
+    this.ensure(32);
+    const v = Buffer.from(this.buf.subarray(this.offset, this.offset + 32));
+    this.offset += 32;
+    return v;
+  }
+
+  readF32(): number {
+    this.ensure(4);
+    const v = this.buf.readFloatLE(this.offset);
+    this.offset += 4;
+    return v;
+  }
+
+  readBytes(n: number): Buffer {
+    this.ensure(n);
+    const v = Buffer.from(this.buf.subarray(this.offset, this.offset + n));
+    this.offset += n;
+    return v;
+  }
+
+  /** STR0_255: 1-byte length prefix + UTF-8 payload */
+  readStr0_255(): string {
+    const len = this.readU8();
+    return this.readBytes(len).toString('utf8');
+  }
+
+  /** B0_32: 1-byte length prefix, max 32 bytes */
+  readB0_32(): Buffer {
+    const len = this.readU8();
+    if (len > 32) throw new RangeError(`B0_32: length ${len} > 32`);
+    return this.readBytes(len);
+  }
+
+  /** B0_255: 1-byte length prefix, max 255 bytes */
+  readB0_255(): Buffer {
+    const len = this.readU8();
+    return this.readBytes(len);
+  }
+
+  /** B0_64K: 2-byte length prefix */
+  readB0_64K(): Buffer {
+    const len = this.readU16();
+    return this.readBytes(len);
+  }
+
+  /** B0_16M: 3-byte length prefix, max 16,777,215 bytes */
+  readB0_16M(): Buffer {
+    const len = this.readU24();
+    return this.readBytes(len);
+  }
+
+  /** SEQ0_255: 1-byte count + repeated elements */
+  readSeq0_255<T>(readFn: (reader: BufferReader) => T): T[] {
+    const count = this.readU8();
+    const result: T[] = [];
+    for (let i = 0; i < count; i++) {
+      result.push(readFn(this));
+    }
+    return result;
+  }
+
+  /** SEQ0_64K: 2-byte count + repeated elements */
+  readSeq0_64K<T>(readFn: (reader: BufferReader) => T): T[] {
+    const count = this.readU16();
+    const result: T[] = [];
+    for (let i = 0; i < count; i++) {
+      result.push(readFn(this));
+    }
+    return result;
+  }
+}
+
+// ── BufferWriter ────────────────────────────────────────────────────
+
+export class BufferWriter {
+  private buf: Buffer;
+  private offset = 0;
+
+  constructor(initialSize = 256) {
+    this.buf = Buffer.allocUnsafe(initialSize);
+  }
+
+  private ensureCapacity(n: number): void {
+    if (this.offset + n > this.buf.length) {
+      let newSize = this.buf.length * 2;
+      while (newSize < this.offset + n) newSize *= 2;
+      const newBuf = Buffer.allocUnsafe(newSize);
+      this.buf.copy(newBuf, 0, 0, this.offset);
+      this.buf = newBuf;
+    }
+  }
+
+  writeBool(v: boolean): void {
+    this.ensureCapacity(1);
+    this.buf[this.offset++] = v ? 1 : 0;
+  }
+
+  writeU8(v: number): void {
+    this.ensureCapacity(1);
+    this.buf[this.offset++] = v & 0xff;
+  }
+
+  /** Write Sv2Option<u32>: 1-byte flag + optional 4-byte u32 LE */
+  writeOptionU32(v: number | null): void {
+    if (v === null) {
+      this.writeU8(0);
+    } else {
+      this.writeU8(1);
+      this.writeU32(v);
+    }
+  }
+
+  writeU16(v: number): void {
+    this.ensureCapacity(2);
+    this.buf.writeUInt16LE(v, this.offset);
+    this.offset += 2;
+  }
+
+  writeU24(v: number): void {
+    this.ensureCapacity(3);
+    this.buf[this.offset] = v & 0xff;
+    this.buf[this.offset + 1] = (v >> 8) & 0xff;
+    this.buf[this.offset + 2] = (v >> 16) & 0xff;
+    this.offset += 3;
+  }
+
+  writeU32(v: number): void {
+    this.ensureCapacity(4);
+    this.buf.writeUInt32LE(v >>> 0, this.offset);
+    this.offset += 4;
+  }
+
+  writeU64(v: bigint): void {
+    this.ensureCapacity(8);
+    this.buf.writeBigUInt64LE(v, this.offset);
+    this.offset += 8;
+  }
+
+  writeU256(v: Buffer): void {
+    if (v.length !== 32) throw new RangeError('U256 must be 32 bytes');
+    this.ensureCapacity(32);
+    v.copy(this.buf, this.offset);
+    this.offset += 32;
+  }
+
+  writeF32(v: number): void {
+    this.ensureCapacity(4);
+    this.buf.writeFloatLE(v, this.offset);
+    this.offset += 4;
+  }
+
+  writeBytes(v: Buffer): void {
+    this.ensureCapacity(v.length);
+    v.copy(this.buf, this.offset);
+    this.offset += v.length;
+  }
+
+  /** STR0_255: 1-byte length prefix + UTF-8 payload */
+  writeStr0_255(v: string): void {
+    const payload = Buffer.from(v, 'utf8');
+    if (payload.length > 255)
+      throw new RangeError(`STR0_255: length ${payload.length} > 255`);
+    this.writeU8(payload.length);
+    this.writeBytes(payload);
+  }
+
+  /** B0_32: 1-byte length prefix, max 32 bytes */
+  writeB0_32(v: Buffer): void {
+    if (v.length > 32) throw new RangeError(`B0_32: length ${v.length} > 32`);
+    this.writeU8(v.length);
+    this.writeBytes(v);
+  }
+
+  /** B0_255: 1-byte length prefix, max 255 bytes */
+  writeB0_255(v: Buffer): void {
+    if (v.length > 255)
+      throw new RangeError(`B0_255: length ${v.length} > 255`);
+    this.writeU8(v.length);
+    this.writeBytes(v);
+  }
+
+  /** B0_64K: 2-byte length prefix */
+  writeB0_64K(v: Buffer): void {
+    if (v.length > 65535)
+      throw new RangeError(`B0_64K: length ${v.length} > 65535`);
+    this.writeU16(v.length);
+    this.writeBytes(v);
+  }
+
+  /** B0_16M: 3-byte length prefix, max 16,777,215 bytes */
+  writeB0_16M(v: Buffer): void {
+    if (v.length > 16777215)
+      throw new RangeError(`B0_16M: length ${v.length} > 16777215`);
+    this.writeU24(v.length);
+    this.writeBytes(v);
+  }
+
+  /** SEQ0_255: 1-byte count + repeated elements */
+  writeSeq0_255<T>(items: T[], writeFn: (writer: BufferWriter, item: T) => void): void {
+    if (items.length > 255)
+      throw new RangeError(`SEQ0_255: count ${items.length} > 255`);
+    this.writeU8(items.length);
+    for (const item of items) {
+      writeFn(this, item);
+    }
+  }
+
+  /** SEQ0_64K: 2-byte count + repeated elements */
+  writeSeq0_64K<T>(items: T[], writeFn: (writer: BufferWriter, item: T) => void): void {
+    if (items.length > 65535)
+      throw new RangeError(`SEQ0_64K: count ${items.length} > 65535`);
+    this.writeU16(items.length);
+    for (const item of items) {
+      writeFn(this, item);
+    }
+  }
+
+  toBuffer(): Buffer {
+    return Buffer.from(this.buf.subarray(0, this.offset));
+  }
+}

src/models/sv2/sv2-constants.ts

@@ -0,0 +1,138 @@
+// ── SV2 Protocol Constants ──────────────────────────────────────────
+
+/** Standard (unencrypted) frame header: 2-byte ext+type + 3-byte length + 1-byte channel bit = 6 */
+export const SV2_HEADER_SIZE = 6;
+
+/** Poly1305 MAC appended to every AEAD ciphertext block */
+export const SV2_MAC_SIZE = 16;
+
+/** Encrypted frame header size: SV2_HEADER_SIZE + SV2_MAC_SIZE = 22 */
+export const SV2_ENCRYPTED_HEADER_SIZE = SV2_HEADER_SIZE + SV2_MAC_SIZE;
+
+/** Max plaintext bytes in a single AEAD chunk (2^16 - 1 - MAC) */
+export const SV2_MAX_PLAINTEXT_CHUNK = 65519;
+
+/** Max ciphertext bytes in a single AEAD chunk (2^16 - 1) */
+export const SV2_MAX_CIPHERTEXT_CHUNK = 65535;
+
+/** EllSwift-encoded public key size (64 bytes) */
+export const SV2_ELLSWIFT_KEY_SIZE = 64;
+
+/** Bit flag in extension_type indicating a channel message */
+export const SV2_CHANNEL_MSG_FLAG = 0x8000;
+
+/** Protocol identifier string used in SetupConnection */
+export const SV2_PROTOCOL_NAME = 'MiningProtocol';
+
+// ── Noise NX Handshake Constants ────────────────────────────────────
+
+/** Noise NX protocol name used to initialize h (ChaCha20-Poly1305) */
+export const SV2_NOISE_PROTOCOL_NAME = 'Noise_NX_Secp256k1+EllSwift_ChaChaPoly_SHA256';
+
+/** Noise NX protocol name for AES-256-GCM cipher */
+export const SV2_NOISE_PROTOCOL_NAME_AESGCM = 'Noise_NX_Secp256k1+EllSwift_AESGCM_SHA256';
+
+/** Noise NX Act 1 size: 64-byte initiator ephemeral EllSwift key */
+export const SV2_NOISE_ACT1_SIZE = 64;
+
+/** Noise NX Act 2 size: 64 (server ephemeral) + 80 (encrypted static) + 90 (encrypted cert) = 234 */
+export const SV2_NOISE_ACT2_SIZE = 234;
+
+/** SIGNATURE_NOISE_MESSAGE payload size (without MAC): version(2) + validFrom(4) + notValidAfter(4) + signature(64) = 74 */
+export const SV2_SIGNATURE_NOISE_MSG_SIZE = 74;
+
+// ── Message Type Enum ───────────────────────────────────────────────
+
+export enum Sv2MsgType {
+  // Common messages
+  SETUP_CONNECTION = 0x00,
+  SETUP_CONNECTION_SUCCESS = 0x01,
+  SETUP_CONNECTION_ERROR = 0x02,
+  CHANNEL_ENDPOINT_CHANGED = 0x03,
+
+  // Mining channel messages
+  OPEN_STANDARD_MINING_CHANNEL = 0x10,
+  OPEN_STANDARD_MINING_CHANNEL_SUCCESS = 0x11,
+  OPEN_STANDARD_MINING_CHANNEL_ERROR = 0x12,
+  CLOSE_CHANNEL = 0x18,
+
+  // Share submission
+  SUBMIT_SHARES_STANDARD = 0x1a,
+  SUBMIT_SHARES_SUCCESS = 0x1c,
+  SUBMIT_SHARES_ERROR = 0x1d,
+
+  // Extended Mining Channels
+  OPEN_EXTENDED_MINING_CHANNEL = 0x13,
+  OPEN_EXTENDED_MINING_CHANNEL_SUCCESS = 0x14,
+  SET_EXTRANONCE_PREFIX = 0x19,
+  SET_GROUP_CHANNEL = 0x25,
+
+  // Share submission (extended)
+  SUBMIT_SHARES_EXTENDED = 0x1b,
+
+  // Job & target
+  NEW_MINING_JOB = 0x15,
+  NEW_EXTENDED_MINING_JOB = 0x1f,
+  SET_NEW_PREV_HASH = 0x20,
+  SET_TARGET = 0x21,
+
+  // Channel management
+  UPDATE_CHANNEL = 0x16,
+  UPDATE_CHANNEL_ERROR = 0x17,
+
+  // Mining Protocol - Custom Job Bridge
+  SET_CUSTOM_MINING_JOB = 0x22,
+  SET_CUSTOM_MINING_JOB_SUCCESS = 0x23,
+  SET_CUSTOM_MINING_JOB_ERROR = 0x24,
+
+  // Reconnect
+  RECONNECT = 0x04,
+
+  // Job Declaration Protocol
+  JDP_ALLOCATE_MINING_JOB_TOKEN = 0x50,
+  JDP_ALLOCATE_MINING_JOB_TOKEN_SUCCESS = 0x51,
+  JDP_PROVIDE_MISSING_TRANSACTIONS = 0x55,
+  JDP_PROVIDE_MISSING_TRANSACTIONS_SUCCESS = 0x56,
+  JDP_DECLARE_MINING_JOB = 0x57,
+  JDP_DECLARE_MINING_JOB_SUCCESS = 0x58,
+  JDP_DECLARE_MINING_JOB_ERROR = 0x59,
+  JDP_PUSH_SOLUTION = 0x60,
+
+  // Template Distribution Protocol
+  TDP_COINBASE_OUTPUT_CONSTRAINTS = 0x70,
+  TDP_NEW_TEMPLATE = 0x71,
+  TDP_SET_NEW_PREV_HASH = 0x72,
+  TDP_REQUEST_TRANSACTION_DATA = 0x73,
+  TDP_REQUEST_TRANSACTION_DATA_SUCCESS = 0x74,
+  TDP_REQUEST_TRANSACTION_DATA_ERROR = 0x75,
+  TDP_SUBMIT_SOLUTION = 0x76,
+}
+
+// ── Protocol Enum ───────────────────────────────────────────────────
+
+export enum Sv2Protocol {
+  MINING = 0,
+  JOB_DECLARATION = 1,
+  TEMPLATE_DISTRIBUTION = 2,
+}
+
+// ── Mining Setup Flags ──────────────────────────────────────────────
+
+export enum Sv2MiningSetupFlags {
+  REQUIRES_STANDARD_JOBS = 1 << 0,
+  REQUIRES_WORK_SELECTION = 1 << 1,
+  REQUIRES_VERSION_ROLLING = 1 << 2,
+}
+
+// ── SetupConnection.Success Flags (Mining Protocol) ─────────────────
+
+export enum Sv2MiningSetupSuccessFlags {
+  REQUIRES_FIXED_VERSION = 1 << 0,
+  REQUIRES_EXTENDED_CHANNELS = 1 << 1,
+}
+
+// ── SetupConnection Flags (Job Declaration Protocol) ────────────────
+
+export enum Sv2JdpSetupFlags {
+  DECLARE_TX_DATA = 1 << 0,
+}

src/models/sv2/sv2-extended-messages.spec.ts

@@ -0,0 +1,188 @@
+import { BufferReader } from './sv2-binary-codec';
+import {
+  Sv2OpenExtendedMiningChannel,
+  serializeOpenExtendedMiningChannel,
+  deserializeOpenExtendedMiningChannel,
+  Sv2OpenExtendedMiningChannelSuccess,
+  serializeOpenExtendedMiningChannelSuccess,
+  deserializeOpenExtendedMiningChannelSuccess,
+  Sv2NewExtendedMiningJob,
+  serializeNewExtendedMiningJob,
+  deserializeNewExtendedMiningJob,
+  Sv2SubmitSharesExtended,
+  serializeSubmitSharesExtended,
+  deserializeSubmitSharesExtended,
+  Sv2SetExtranoncePrefix,
+  serializeSetExtranoncePrefix,
+  deserializeSetExtranoncePrefix,
+  Sv2SetGroupChannel,
+  serializeSetGroupChannel,
+  deserializeSetGroupChannel,
+} from './sv2-extended-messages';
+
+function roundTrip<T>(
+  msg: T,
+  serialize: (m: T) => Buffer,
+  deserialize: (r: BufferReader) => T,
+): T {
+  const buf = serialize(msg);
+  return deserialize(new BufferReader(buf));
+}
+
+describe('SV2 Extended Mining Channel Messages', () => {
+  it('OpenExtendedMiningChannel round-trips', () => {
+    const maxTarget = Buffer.alloc(32, 0x00);
+    maxTarget[0] = 0xff;
+    const msg: Sv2OpenExtendedMiningChannel = {
+      requestId: 1,
+      userIdentity: 'bc1qtest.worker1',
+      nominalHashRate: 500000.0,
+      maxTarget,
+      minExtranonceSize: 8,
+    };
+    const result = roundTrip(msg, serializeOpenExtendedMiningChannel, deserializeOpenExtendedMiningChannel);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.userIdentity).toBe(msg.userIdentity);
+    expect(result.nominalHashRate).toBeCloseTo(msg.nominalHashRate, 0);
+    expect(result.maxTarget).toEqual(msg.maxTarget);
+    expect(result.minExtranonceSize).toBe(msg.minExtranonceSize);
+  });
+
+  it('OpenExtendedMiningChannelSuccess round-trips', () => {
+    const target = Buffer.alloc(32);
+    target[0] = 0xff;
+    const msg: Sv2OpenExtendedMiningChannelSuccess = {
+      requestId: 1,
+      channelId: 42,
+      target,
+      extranonceSize: 8,
+      extranoncePrefix: Buffer.from([0x00, 0x00, 0x00, 0x01]),
+      groupChannelId: 0,
+    };
+    const result = roundTrip(
+      msg,
+      serializeOpenExtendedMiningChannelSuccess,
+      deserializeOpenExtendedMiningChannelSuccess,
+    );
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.channelId).toBe(msg.channelId);
+    expect(result.target).toEqual(msg.target);
+    expect(result.extranonceSize).toBe(msg.extranonceSize);
+    expect(result.extranoncePrefix).toEqual(msg.extranoncePrefix);
+    expect(result.groupChannelId).toBe(msg.groupChannelId);
+  });
+
+  it('NewExtendedMiningJob round-trips with minNtime (mine immediately)', () => {
+    const hash1 = Buffer.alloc(32, 0xaa);
+    const hash2 = Buffer.alloc(32, 0xbb);
+    const msg: Sv2NewExtendedMiningJob = {
+      channelId: 1,
+      jobId: 100,
+      minNtime: 1700000000,
+      version: 0x20000000,
+      versionRollingAllowed: true,
+      merklePath: [hash1, hash2],
+      coinbasePrefix: Buffer.from('deadbeef', 'hex'),
+      coinbaseSuffix: Buffer.from('cafebabe', 'hex'),
+    };
+    const result = roundTrip(msg, serializeNewExtendedMiningJob, deserializeNewExtendedMiningJob);
+    expect(result.channelId).toBe(msg.channelId);
+    expect(result.jobId).toBe(msg.jobId);
+    expect(result.minNtime).toBe(msg.minNtime);
+    expect(result.version).toBe(msg.version);
+    expect(result.versionRollingAllowed).toBe(msg.versionRollingAllowed);
+    expect(result.merklePath).toHaveLength(2);
+    expect(result.merklePath[0]).toEqual(hash1);
+    expect(result.merklePath[1]).toEqual(hash2);
+    expect(result.coinbasePrefix).toEqual(msg.coinbasePrefix);
+    expect(result.coinbaseSuffix).toEqual(msg.coinbaseSuffix);
+  });
+
+  it('NewExtendedMiningJob with null minNtime (future job)', () => {
+    const msg: Sv2NewExtendedMiningJob = {
+      channelId: 1,
+      jobId: 1,
+      minNtime: null,
+      version: 0x20000000,
+      versionRollingAllowed: false,
+      merklePath: [],
+      coinbasePrefix: Buffer.alloc(0),
+      coinbaseSuffix: Buffer.alloc(0),
+    };
+    const result = roundTrip(msg, serializeNewExtendedMiningJob, deserializeNewExtendedMiningJob);
+    expect(result.merklePath).toHaveLength(0);
+    expect(result.minNtime).toBeNull();
+    expect(result.versionRollingAllowed).toBe(false);
+  });
+
+  it('SubmitSharesExtended round-trips', () => {
+    const msg: Sv2SubmitSharesExtended = {
+      channelId: 1,
+      sequenceNumber: 42,
+      jobId: 100,
+      nonce: 0xdeadbeef,
+      ntime: 1700000000,
+      version: 0x20000000,
+      extranonce: Buffer.from([0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07]),
+    };
+    const result = roundTrip(msg, serializeSubmitSharesExtended, deserializeSubmitSharesExtended);
+    expect(result.channelId).toBe(msg.channelId);
+    expect(result.sequenceNumber).toBe(msg.sequenceNumber);
+    expect(result.jobId).toBe(msg.jobId);
+    expect(result.nonce).toBe(msg.nonce);
+    expect(result.ntime).toBe(msg.ntime);
+    expect(result.version).toBe(msg.version);
+    expect(result.extranonce).toEqual(msg.extranonce);
+  });
+
+  it('SubmitSharesExtended with short extranonce', () => {
+    const msg: Sv2SubmitSharesExtended = {
+      channelId: 1,
+      sequenceNumber: 1,
+      jobId: 1,
+      nonce: 0,
+      ntime: 1700000000,
+      version: 0x20000000,
+      extranonce: Buffer.from([0xab]),
+    };
+    const result = roundTrip(msg, serializeSubmitSharesExtended, deserializeSubmitSharesExtended);
+    expect(result.extranonce).toEqual(Buffer.from([0xab]));
+  });
+
+  it('SetExtranoncePrefix round-trips', () => {
+    const msg: Sv2SetExtranoncePrefix = {
+      channelId: 5,
+      extranoncePrefix: Buffer.from([0x00, 0x00, 0x00, 0x02]),
+    };
+    const result = roundTrip(msg, serializeSetExtranoncePrefix, deserializeSetExtranoncePrefix);
+    expect(result.channelId).toBe(msg.channelId);
+    expect(result.extranoncePrefix).toEqual(msg.extranoncePrefix);
+  });
+
+  it('SetGroupChannel round-trips', () => {
+    const msg: Sv2SetGroupChannel = {
+      groupChannelId: 10,
+      channelIds: [42, 43, 44],
+    };
+    const result = roundTrip(msg, serializeSetGroupChannel, deserializeSetGroupChannel);
+    expect(result).toEqual(msg);
+  });
+
+  it('serialized SubmitSharesExtended has correct byte layout', () => {
+    const msg: Sv2SubmitSharesExtended = {
+      channelId: 1,
+      sequenceNumber: 2,
+      jobId: 3,
+      nonce: 4,
+      ntime: 5,
+      version: 6,
+      extranonce: Buffer.from([0xab, 0xcd]),
+    };
+    const buf = serializeSubmitSharesExtended(msg);
+    // 6 * U32(4) = 24 + B0_32(1+2) = 27
+    expect(buf.length).toBe(27);
+    expect(buf.readUInt32LE(0)).toBe(1);
+    expect(buf.readUInt32LE(4)).toBe(2);
+    expect(buf.readUInt32LE(8)).toBe(3);
+  });
+});

src/models/sv2/sv2-extended-messages.ts

@@ -0,0 +1,184 @@
+// ── SV2 Extended Mining Channel Messages ────────────────────────────
+// Interfaces + serialize/deserialize for extended channel message types.
+
+import { BufferReader, BufferWriter } from './sv2-binary-codec';
+
+// ── OpenExtendedMiningChannel (0x13) ───────────────────────────────
+
+export interface Sv2OpenExtendedMiningChannel {
+  requestId: number;         // U32
+  userIdentity: string;      // STR0_255
+  nominalHashRate: number;   // F32
+  maxTarget: Buffer;         // U256 (32 bytes LE)
+  minExtranonceSize: number; // U16
+}
+
+export function serializeOpenExtendedMiningChannel(msg: Sv2OpenExtendedMiningChannel): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeStr0_255(msg.userIdentity);
+  w.writeF32(msg.nominalHashRate);
+  w.writeU256(msg.maxTarget);
+  w.writeU16(msg.minExtranonceSize);
+  return w.toBuffer();
+}
+
+export function deserializeOpenExtendedMiningChannel(reader: BufferReader): Sv2OpenExtendedMiningChannel {
+  return {
+    requestId: reader.readU32(),
+    userIdentity: reader.readStr0_255(),
+    nominalHashRate: reader.readF32(),
+    maxTarget: reader.readU256(),
+    minExtranonceSize: reader.readU16(),
+  };
+}
+
+// ── OpenExtendedMiningChannel.Success (0x14) ───────────────────────
+
+export interface Sv2OpenExtendedMiningChannelSuccess {
+  requestId: number;       // U32
+  channelId: number;       // U32
+  target: Buffer;          // U256
+  extranonceSize: number;  // U16
+  extranoncePrefix: Buffer; // B0_32
+  groupChannelId: number;  // U32
+}
+
+export function serializeOpenExtendedMiningChannelSuccess(msg: Sv2OpenExtendedMiningChannelSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeU32(msg.channelId);
+  w.writeU256(msg.target);
+  w.writeU16(msg.extranonceSize);
+  w.writeB0_32(msg.extranoncePrefix);
+  w.writeU32(msg.groupChannelId);
+  return w.toBuffer();
+}
+
+export function deserializeOpenExtendedMiningChannelSuccess(reader: BufferReader): Sv2OpenExtendedMiningChannelSuccess {
+  return {
+    requestId: reader.readU32(),
+    channelId: reader.readU32(),
+    target: reader.readU256(),
+    extranonceSize: reader.readU16(),
+    extranoncePrefix: reader.readB0_32(),
+    groupChannelId: reader.readU32(),
+  };
+}
+
+// ── NewExtendedMiningJob (0x1f) ────────────────────────────────────
+
+export interface Sv2NewExtendedMiningJob {
+  channelId: number;            // U32
+  jobId: number;                // U32
+  minNtime: number | null;      // Sv2Option<U32> - null = future job (activated by SetNewPrevHash), Some(ts) = mine immediately
+  version: number;              // U32
+  versionRollingAllowed: boolean; // BOOL
+  merklePath: Buffer[];         // SEQ0_255<U256>
+  coinbasePrefix: Buffer;       // B0_64K
+  coinbaseSuffix: Buffer;       // B0_64K
+}
+
+export function serializeNewExtendedMiningJob(msg: Sv2NewExtendedMiningJob): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.jobId);
+  w.writeOptionU32(msg.minNtime);
+  w.writeU32(msg.version);
+  w.writeBool(msg.versionRollingAllowed);
+  w.writeSeq0_255(msg.merklePath, (writer, hash) => writer.writeU256(hash));
+  w.writeB0_64K(msg.coinbasePrefix);
+  w.writeB0_64K(msg.coinbaseSuffix);
+  return w.toBuffer();
+}
+
+export function deserializeNewExtendedMiningJob(reader: BufferReader): Sv2NewExtendedMiningJob {
+  return {
+    channelId: reader.readU32(),
+    jobId: reader.readU32(),
+    minNtime: reader.readOptionU32(),
+    version: reader.readU32(),
+    versionRollingAllowed: reader.readBool(),
+    merklePath: reader.readSeq0_255((r) => r.readU256()),
+    coinbasePrefix: reader.readB0_64K(),
+    coinbaseSuffix: reader.readB0_64K(),
+  };
+}
+
+// ── SubmitSharesExtended (0x1b) ────────────────────────────────────
+
+export interface Sv2SubmitSharesExtended {
+  channelId: number;     // U32
+  sequenceNumber: number; // U32
+  jobId: number;         // U32
+  nonce: number;         // U32
+  ntime: number;         // U32
+  version: number;       // U32
+  extranonce: Buffer;    // B0_32
+}
+
+export function serializeSubmitSharesExtended(msg: Sv2SubmitSharesExtended): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.sequenceNumber);
+  w.writeU32(msg.jobId);
+  w.writeU32(msg.nonce);
+  w.writeU32(msg.ntime);
+  w.writeU32(msg.version);
+  w.writeB0_32(msg.extranonce);
+  return w.toBuffer();
+}
+
+export function deserializeSubmitSharesExtended(reader: BufferReader): Sv2SubmitSharesExtended {
+  return {
+    channelId: reader.readU32(),
+    sequenceNumber: reader.readU32(),
+    jobId: reader.readU32(),
+    nonce: reader.readU32(),
+    ntime: reader.readU32(),
+    version: reader.readU32(),
+    extranonce: reader.readB0_32(),
+  };
+}
+
+// ── SetExtranoncePrefix (0x19) ─────────────────────────────────────
+
+export interface Sv2SetExtranoncePrefix {
+  channelId: number;       // U32
+  extranoncePrefix: Buffer; // B0_32
+}
+
+export function serializeSetExtranoncePrefix(msg: Sv2SetExtranoncePrefix): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeB0_32(msg.extranoncePrefix);
+  return w.toBuffer();
+}
+
+export function deserializeSetExtranoncePrefix(reader: BufferReader): Sv2SetExtranoncePrefix {
+  return {
+    channelId: reader.readU32(),
+    extranoncePrefix: reader.readB0_32(),
+  };
+}
+
+// ── SetGroupChannel (0x25) ─────────────────────────────────────────
+
+export interface Sv2SetGroupChannel {
+  groupChannelId: number; // U32
+  channelIds: number[];   // SEQ0_64K[U32]
+}
+
+export function serializeSetGroupChannel(msg: Sv2SetGroupChannel): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.groupChannelId);
+  w.writeSeq0_64K(msg.channelIds, (writer, id) => writer.writeU32(id));
+  return w.toBuffer();
+}
+
+export function deserializeSetGroupChannel(reader: BufferReader): Sv2SetGroupChannel {
+  return {
+    groupChannelId: reader.readU32(),
+    channelIds: reader.readSeq0_64K((r) => r.readU32()),
+  };
+}

src/models/sv2/sv2-extranonce-manager.spec.ts

@@ -0,0 +1,114 @@
+import { Sv2ExtranonceManager } from './sv2-extranonce-manager';
+
+
+describe('Sv2ExtranonceManager', () => {
+  it('allocates unique prefixes for different channels', () => {
+    const mgr = new Sv2ExtranonceManager();
+    const p1 = mgr.allocate(1);
+    const p2 = mgr.allocate(2);
+    const p3 = mgr.allocate(3);
+
+    expect(p1).not.toEqual(p2);
+    expect(p2).not.toEqual(p3);
+    expect(p1).not.toEqual(p3);
+  });
+
+  it('returns same prefix for same channel on re-allocation', () => {
+    const mgr = new Sv2ExtranonceManager();
+    const p1a = mgr.allocate(1);
+    const p1b = mgr.allocate(1);
+    expect(p1a).toEqual(p1b);
+  });
+
+  it('prefix is 4 bytes by default', () => {
+    const mgr = new Sv2ExtranonceManager();
+    const p = mgr.allocate(1);
+    expect(p.length).toBe(4);
+  });
+
+  it('minerExtranonceSize is total minus prefix', () => {
+    const mgr = new Sv2ExtranonceManager(4, 8);
+    expect(mgr.minerExtranonceSize).toBe(4);
+
+    const mgr2 = new Sv2ExtranonceManager(2, 6);
+    expect(mgr2.minerExtranonceSize).toBe(4);
+  });
+
+  it('releases prefix and allows reuse', () => {
+    const mgr = new Sv2ExtranonceManager();
+    const p1 = mgr.allocate(1);
+    expect(mgr.allocatedCount).toBe(1);
+
+    mgr.release(1);
+    expect(mgr.allocatedCount).toBe(0);
+    expect(mgr.getPrefix(1)).toBeUndefined();
+
+    // Should be able to allocate again (may get same or different prefix)
+    const p2 = mgr.allocate(10);
+    expect(p2.length).toBe(4);
+    expect(mgr.allocatedCount).toBe(1);
+  });
+
+  it('release is idempotent for unknown channels', () => {
+    const mgr = new Sv2ExtranonceManager();
+    expect(() => mgr.release(999)).not.toThrow();
+  });
+
+  it('getPrefix returns undefined for unallocated channel', () => {
+    const mgr = new Sv2ExtranonceManager();
+    expect(mgr.getPrefix(42)).toBeUndefined();
+  });
+
+  it('getPrefix returns the allocated prefix', () => {
+    const mgr = new Sv2ExtranonceManager();
+    const p = mgr.allocate(1);
+    expect(mgr.getPrefix(1)).toEqual(p);
+  });
+
+  it('handles many allocations without collision', () => {
+    const mgr = new Sv2ExtranonceManager();
+    const prefixes = new Set<string>();
+
+    for (let i = 1; i <= 1000; i++) {
+      const p = mgr.allocate(i);
+      const hex = p.toString('hex');
+      expect(prefixes.has(hex)).toBe(false);
+      prefixes.add(hex);
+    }
+
+    expect(mgr.allocatedCount).toBe(1000);
+  });
+
+  it('works with 2-byte prefix size', () => {
+    const mgr = new Sv2ExtranonceManager(2, 4);
+    const p = mgr.allocate(1);
+    expect(p.length).toBe(2);
+    expect(mgr.minerExtranonceSize).toBe(2);
+  });
+
+  it('reuses released prefix slot', () => {
+    const mgr = new Sv2ExtranonceManager();
+    const p1 = mgr.allocate(1);
+    mgr.allocate(2);
+    mgr.release(1);
+
+    // Allocate a new channel - p1's prefix should be available
+    const p3 = mgr.allocate(3);
+    expect(p3.length).toBe(4);
+    expect(mgr.allocatedCount).toBe(2);
+  });
+
+  it('tracks allocatedCount correctly', () => {
+    const mgr = new Sv2ExtranonceManager();
+    expect(mgr.allocatedCount).toBe(0);
+    mgr.allocate(1);
+    expect(mgr.allocatedCount).toBe(1);
+    mgr.allocate(2);
+    expect(mgr.allocatedCount).toBe(2);
+    mgr.release(1);
+    expect(mgr.allocatedCount).toBe(1);
+    mgr.release(2);
+    expect(mgr.allocatedCount).toBe(0);
+  });
+
+});

src/models/sv2/sv2-extranonce-manager.ts

@@ -0,0 +1,113 @@
+// ── SV2 Extranonce Manager ──────────────────────────────────────────
+// Manages extranonce prefix allocation for extended mining channels.
+// Ensures no two channels share the same prefix to prevent hash collisions.
+
+export class Sv2ExtranonceManager {
+  private nextPrefix: number;
+  private readonly workerOffset: number;
+  private readonly maxPrefix: number;
+  private allocatedPrefixes = new Map<number, number>(); // channelId → prefix
+  private usedPrefixes = new Set<number>();
+  private readonly prefixSize: number;
+  private readonly totalExtranonceSize: number;
+
+  /**
+   * @param prefixSize Bytes used for pool-assigned prefix (default 4)
+   * @param totalExtranonceSize Total extranonce bytes (default 12: 4 prefix + 8 miner-controlled).
+   *        Must match MiningJob.ts's coinbase slot size (12 bytes) — both
+   *        protocols share the same coinbase template. Bumped from the
+   *        previous 8-byte total because the Braiins Hashpower marketplace
+   *        requires extranonce2_size >= 7 (compatibility spec).
+   */
+  constructor(prefixSize = 4, totalExtranonceSize = 12) {
+    this.prefixSize = prefixSize;
+    this.totalExtranonceSize = totalExtranonceSize;
+
+    const workerId = 0;
+    const bitsPerWorker = (prefixSize - 1) * 8;
+    this.workerOffset = workerId * Math.pow(2, bitsPerWorker);
+    this.maxPrefix = Math.pow(2, bitsPerWorker) - 1; // max within this worker's slice
+    this.nextPrefix = 1;
+  }
+
+  get minerExtranonceSize(): number {
+    return this.totalExtranonceSize - this.prefixSize;
+  }
+
+  /**
+   * Allocate a unique extranonce prefix for a channel.
+   * Returns a Buffer of `prefixSize` bytes.
+   */
+  allocate(channelId: number): Buffer {
+    // Check if already allocated
+    if (this.allocatedPrefixes.has(channelId)) {
+      const existing = this.allocatedPrefixes.get(channelId)!;
+      return this.prefixToBuffer(existing);
+    }
+
+    // Find next available prefix within this worker's partition
+    let localPrefix = this.nextPrefix;
+    let attempts = 0;
+    const globalPrefix = () => this.workerOffset + localPrefix;
+
+    while (this.usedPrefixes.has(globalPrefix()) && attempts <= this.maxPrefix) {
+      localPrefix = localPrefix + 1;
+      if (localPrefix > this.maxPrefix) localPrefix = 1; // Wrap within partition, skip 0
+      attempts++;
+    }
+
+    if (this.usedPrefixes.has(globalPrefix())) {
+      throw new Error('Extranonce prefix space exhausted');
+    }
+
+    const prefix = globalPrefix();
+    this.allocatedPrefixes.set(channelId, prefix);
+    this.usedPrefixes.add(prefix);
+    this.nextPrefix = localPrefix + 1;
+    if (this.nextPrefix > this.maxPrefix) this.nextPrefix = 1;
+
+    return this.prefixToBuffer(prefix);
+  }
+
+  /**
+   * Release the prefix allocated to a channel.
+   */
+  release(channelId: number): void {
+    const prefix = this.allocatedPrefixes.get(channelId);
+    if (prefix !== undefined) {
+      this.allocatedPrefixes.delete(channelId);
+      this.usedPrefixes.delete(prefix);
+    }
+  }
+
+  /**
+   * Get the prefix for a channel, or undefined if not allocated.
+   */
+  getPrefix(channelId: number): Buffer | undefined {
+    const prefix = this.allocatedPrefixes.get(channelId);
+    if (prefix === undefined) return undefined;
+    return this.prefixToBuffer(prefix);
+  }
+
+  get allocatedCount(): number {
+    return this.allocatedPrefixes.size;
+  }
+
+  private prefixToBuffer(prefix: number): Buffer {
+    const buf = Buffer.alloc(this.prefixSize);
+    // Write as big-endian so prefix 1 = 0x00000001
+    if (this.prefixSize === 4) {
+      buf.writeUInt32BE(prefix, 0);
+    } else if (this.prefixSize === 2) {
+      buf.writeUInt16BE(prefix, 0);
+    } else {
+      // Generic: write big-endian
+      let val = prefix;
+      for (let i = this.prefixSize - 1; i >= 0; i--) {
+        buf[i] = val & 0xff;
+        val = val >>> 8;
+      }
+    }
+    return buf;
+  }
+}

src/models/sv2/sv2-frame.spec.ts

@@ -0,0 +1,243 @@
+import {
+  encodeFrameHeader,
+  decodeFrameHeader,
+  isChannelMessage,
+  plaintextToCiphertextLength,
+  ciphertextToPlaintextLength,
+  Sv2FrameReader,
+  Sv2FrameWriter,
+  Sv2FrameHeader,
+} from './sv2-frame';
+import { SV2_CHANNEL_MSG_FLAG, SV2_MAC_SIZE, SV2_MAX_PLAINTEXT_CHUNK } from './sv2-constants';
+
+describe('SV2 Frame', () => {
+  // ── Header Encode / Decode ──────────────────────────────────────────
+
+  describe('frame header', () => {
+    it('should encode and decode a basic header', () => {
+      const header: Sv2FrameHeader = {
+        extensionType: 0x0000,
+        msgType: 0x10,
+        msgLength: 42,
+      };
+      const buf = encodeFrameHeader(header);
+      expect(buf.length).toBe(6);
+      const decoded = decodeFrameHeader(buf);
+      expect(decoded).toEqual(header);
+    });
+
+    it('should handle max msgLength (24-bit)', () => {
+      const header: Sv2FrameHeader = {
+        extensionType: 0,
+        msgType: 0xff,
+        msgLength: 0xffffff,
+      };
+      const buf = encodeFrameHeader(header);
+      const decoded = decodeFrameHeader(buf);
+      expect(decoded.msgLength).toBe(0xffffff);
+    });
+
+    it('should preserve channel message flag', () => {
+      const header: Sv2FrameHeader = {
+        extensionType: SV2_CHANNEL_MSG_FLAG | 0x01,
+        msgType: 0x1a,
+        msgLength: 24,
+      };
+      const buf = encodeFrameHeader(header);
+      const decoded = decodeFrameHeader(buf);
+      expect(decoded.extensionType).toBe(SV2_CHANNEL_MSG_FLAG | 0x01);
+      expect(isChannelMessage(decoded)).toBe(true);
+    });
+
+    it('should detect non-channel messages', () => {
+      const header: Sv2FrameHeader = {
+        extensionType: 0x0000,
+        msgType: 0x00,
+        msgLength: 10,
+      };
+      expect(isChannelMessage(header)).toBe(false);
+    });
+
+    it('should throw on buffer too short', () => {
+      expect(() => decodeFrameHeader(Buffer.alloc(5))).toThrow(RangeError);
+    });
+  });
+
+  // ── Ciphertext Length Calculations ──────────────────────────────────
+
+  describe('ciphertext length calculations', () => {
+    it('should return 0 for 0-length plaintext', () => {
+      expect(plaintextToCiphertextLength(0)).toBe(0);
+      expect(ciphertextToPlaintextLength(0)).toBe(0);
+    });
+
+    it('should add one MAC for small payload', () => {
+      expect(plaintextToCiphertextLength(100)).toBe(100 + SV2_MAC_SIZE);
+    });
+
+    it('should handle exactly one full chunk', () => {
+      const ct = plaintextToCiphertextLength(SV2_MAX_PLAINTEXT_CHUNK);
+      expect(ct).toBe(SV2_MAX_PLAINTEXT_CHUNK + SV2_MAC_SIZE);
+    });
+
+    it('should handle one full chunk + 1 byte remainder', () => {
+      const ct = plaintextToCiphertextLength(SV2_MAX_PLAINTEXT_CHUNK + 1);
+      expect(ct).toBe(SV2_MAX_PLAINTEXT_CHUNK + SV2_MAC_SIZE + 1 + SV2_MAC_SIZE);
+    });
+
+    it('plaintext -> ciphertext -> plaintext round-trips', () => {
+      const sizes = [0, 1, 100, SV2_MAX_PLAINTEXT_CHUNK, SV2_MAX_PLAINTEXT_CHUNK + 1, SV2_MAX_PLAINTEXT_CHUNK * 2 + 500];
+      for (const pt of sizes) {
+        const ct = plaintextToCiphertextLength(pt);
+        expect(ciphertextToPlaintextLength(ct)).toBe(pt);
+      }
+    });
+
+    it('should throw for invalid ciphertext length (remainder too small)', () => {
+      // A remainder of exactly SV2_MAC_SIZE would mean 0 plaintext bytes but still a chunk
+      // Actually that's valid (0 plaintext + 16 MAC). Let's test remainder < MAC
+      expect(() => ciphertextToPlaintextLength(5)).toThrow(RangeError);
+    });
+  });
+
+  // ── Plaintext Frame Reader / Writer ─────────────────────────────────
+
+  describe('plaintext framing', () => {
+    it('should write and read a complete plaintext frame', () => {
+      const writer = new Sv2FrameWriter(null);
+      const header: Sv2FrameHeader = {
+        extensionType: 0,
+        msgType: 0x00,
+        msgLength: 5,
+      };
+      const payload = Buffer.from('hello');
+      const wire = writer.writeFrame(header, payload);
+
+      const reader = new Sv2FrameReader(null);
+      const frames = reader.feed(wire);
+      expect(frames.length).toBe(1);
+      expect(frames[0].header.msgType).toBe(0x00);
+      expect(frames[0].payload.toString()).toBe('hello');
+    });
+
+    it('should handle fragmented TCP delivery', () => {
+      const writer = new Sv2FrameWriter(null);
+      const header: Sv2FrameHeader = {
+        extensionType: 0,
+        msgType: 0x10,
+        msgLength: 10,
+      };
+      const payload = Buffer.alloc(10, 0xab);
+      const wire = writer.writeFrame(header, payload);
+
+      const reader = new Sv2FrameReader(null);
+
+      // Feed byte by byte
+      let frames: any[] = [];
+      for (let i = 0; i < wire.length; i++) {
+        const chunk = wire.subarray(i, i + 1);
+        frames = frames.concat(reader.feed(Buffer.from(chunk)));
+      }
+
+      expect(frames.length).toBe(1);
+      expect(frames[0].header.msgType).toBe(0x10);
+      expect(frames[0].payload).toEqual(payload);
+    });
+
+    it('should parse multiple frames in one feed', () => {
+      const writer = new Sv2FrameWriter(null);
+      const frames: Buffer[] = [];
+      for (let i = 0; i < 3; i++) {
+        const header: Sv2FrameHeader = {
+          extensionType: 0,
+          msgType: i,
+          msgLength: 4,
+        };
+        frames.push(writer.writeFrame(header, Buffer.alloc(4, i)));
+      }
+
+      const reader = new Sv2FrameReader(null);
+      const result = reader.feed(Buffer.concat(frames));
+      expect(result.length).toBe(3);
+      for (let i = 0; i < 3; i++) {
+        expect(result[i].header.msgType).toBe(i);
+        expect(result[i].payload).toEqual(Buffer.alloc(4, i));
+      }
+    });
+
+    it('should handle zero-length payload', () => {
+      const writer = new Sv2FrameWriter(null);
+      const header: Sv2FrameHeader = {
+        extensionType: 0,
+        msgType: 0x01,
+        msgLength: 0,
+      };
+      const wire = writer.writeFrame(header, Buffer.alloc(0));
+
+      const reader = new Sv2FrameReader(null);
+      const frames = reader.feed(wire);
+      expect(frames.length).toBe(1);
+      expect(frames[0].payload.length).toBe(0);
+    });
+  });
+
+  // ── Encrypted Frame Reader / Writer ─────────────────────────────────
+
+  describe('encrypted framing', () => {
+    it('should write and read encrypted frames with mock cipher', () => {
+      // Simple XOR "encryption" for testing frame logic
+      const xorKey = 0x42;
+      const encrypt = (pt: Buffer) => {
+        const ct = Buffer.alloc(pt.length + SV2_MAC_SIZE);
+        for (let i = 0; i < pt.length; i++) ct[i] = pt[i] ^ xorKey;
+        // Fake MAC: zeros
+        return ct;
+      };
+      const decrypt = (ct: Buffer) => {
+        const pt = Buffer.alloc(ct.length - SV2_MAC_SIZE);
+        for (let i = 0; i < pt.length; i++) pt[i] = ct[i] ^ xorKey;
+        return pt;
+      };
+
+      const writer = new Sv2FrameWriter(encrypt);
+      const header: Sv2FrameHeader = {
+        extensionType: 0,
+        msgType: 0x10,
+        msgLength: 8,
+      };
+      const payload = Buffer.from('testdata');
+      const wire = writer.writeFrame(header, payload);
+
+      const reader = new Sv2FrameReader(decrypt);
+      const frames = reader.feed(wire);
+      expect(frames.length).toBe(1);
+      expect(frames[0].header.msgType).toBe(0x10);
+      expect(frames[0].payload.toString()).toBe('testdata');
+    });
+
+    it('should switch from plaintext to encrypted mode', () => {
+      const encrypt = (pt: Buffer) => Buffer.concat([pt, Buffer.alloc(SV2_MAC_SIZE)]);
+      const decrypt = (ct: Buffer) => ct.subarray(0, ct.length - SV2_MAC_SIZE);
+
+      // Start in plaintext mode
+      const writer = new Sv2FrameWriter(null);
+      const reader = new Sv2FrameReader(null);
+
+      const plainHeader: Sv2FrameHeader = { extensionType: 0, msgType: 0x00, msgLength: 3 };
+      const plainWire = writer.writeFrame(plainHeader, Buffer.from('abc'));
+      let frames = reader.feed(plainWire);
+      expect(frames.length).toBe(1);
+      expect(frames[0].payload.toString()).toBe('abc');
+
+      // Switch to encrypted
+      writer.setEncryptFn(encrypt);
+      reader.setDecryptFn(decrypt);
+
+      const encHeader: Sv2FrameHeader = { extensionType: 0, msgType: 0x01, msgLength: 3 };
+      const encWire = writer.writeFrame(encHeader, Buffer.from('xyz'));
+      frames = reader.feed(encWire);
+      expect(frames.length).toBe(1);
+      expect(frames[0].payload.toString()).toBe('xyz');
+    });
+  });
+});

src/models/sv2/sv2-frame.ts

@@ -0,0 +1,232 @@
+// ── SV2 Frame Encoding / Decoding ───────────────────────────────────
+// Handles 6-byte frame headers, encrypted framing with ChaCha20-Poly1305
+// AEAD chunking, and incremental TCP reassembly.
+
+import {
+  SV2_HEADER_SIZE,
+  SV2_MAC_SIZE,
+  SV2_ENCRYPTED_HEADER_SIZE,
+  SV2_MAX_PLAINTEXT_CHUNK,
+  SV2_CHANNEL_MSG_FLAG,
+} from './sv2-constants';
+
+// ── Frame Header ────────────────────────────────────────────────────
+
+export interface Sv2FrameHeader {
+  extensionType: number; // U16 (includes channel msg bit)
+  msgType: number; // U8
+  msgLength: number; // U24 (payload byte count)
+}
+
+/**
+ * Encode a 6-byte SV2 frame header.
+ * extension_type[0..1] | msg_type[2] | msg_length[3..5]
+ */
+export function encodeFrameHeader(header: Sv2FrameHeader): Buffer {
+  const buf = Buffer.alloc(SV2_HEADER_SIZE);
+  buf.writeUInt16LE(header.extensionType, 0);
+  buf[2] = header.msgType & 0xff;
+  buf[3] = header.msgLength & 0xff;
+  buf[4] = (header.msgLength >> 8) & 0xff;
+  buf[5] = (header.msgLength >> 16) & 0xff;
+  return buf;
+}
+
+/**
+ * Decode a 6-byte SV2 frame header.
+ */
+export function decodeFrameHeader(buf: Buffer): Sv2FrameHeader {
+  if (buf.length < SV2_HEADER_SIZE) {
+    throw new RangeError(`Frame header requires ${SV2_HEADER_SIZE} bytes, got ${buf.length}`);
+  }
+  const extensionType = buf.readUInt16LE(0);
+  const msgType = buf[2];
+  const msgLength = buf[3] | (buf[4] << 8) | (buf[5] << 16);
+  return { extensionType, msgType, msgLength };
+}
+
+/**
+ * Check if a frame header indicates a channel message.
+ */
+export function isChannelMessage(header: Sv2FrameHeader): boolean {
+  return (header.extensionType & SV2_CHANNEL_MSG_FLAG) !== 0;
+}
+
+// ── Ciphertext / Plaintext Size Calculations ────────────────────────
+
+/**
+ * Calculate ciphertext length from plaintext length.
+ * Each chunk of up to 65519 plaintext bytes gets a 16-byte MAC.
+ */
+export function plaintextToCiphertextLength(plaintextLen: number): number {
+  if (plaintextLen === 0) return 0;
+  const fullChunks = Math.floor(plaintextLen / SV2_MAX_PLAINTEXT_CHUNK);
+  const remainder = plaintextLen % SV2_MAX_PLAINTEXT_CHUNK;
+  let len = fullChunks * (SV2_MAX_PLAINTEXT_CHUNK + SV2_MAC_SIZE);
+  if (remainder > 0) {
+    len += remainder + SV2_MAC_SIZE;
+  }
+  return len;
+}
+
+/**
+ * Calculate plaintext length from ciphertext length.
+ */
+export function ciphertextToPlaintextLength(ciphertextLen: number): number {
+  if (ciphertextLen === 0) return 0;
+  const chunkSize = SV2_MAX_PLAINTEXT_CHUNK + SV2_MAC_SIZE;
+  const fullChunks = Math.floor(ciphertextLen / chunkSize);
+  const remainder = ciphertextLen % chunkSize;
+  let len = fullChunks * SV2_MAX_PLAINTEXT_CHUNK;
+  if (remainder > 0) {
+    if (remainder <= SV2_MAC_SIZE) {
+      throw new RangeError('Invalid ciphertext length: remainder chunk too small for MAC');
+    }
+    len += remainder - SV2_MAC_SIZE;
+  }
+  return len;
+}
+
+// ── Decryption / Encryption Function Types ──────────────────────────
+
+export type DecryptFn = (ciphertext: Buffer) => Buffer;
+export type EncryptFn = (plaintext: Buffer) => Buffer;
+
+// ── Frame Reader (TCP reassembly + decryption) ──────────────────────
+
+interface ParsedFrame {
+  header: Sv2FrameHeader;
+  payload: Buffer;
+}
+
+const enum ReaderState {
+  READING_HEADER,
+  READING_PAYLOAD,
+}
+
+export class Sv2FrameReader {
+  private decryptFn: DecryptFn | null;
+  private buf: Buffer = Buffer.alloc(0);
+  private state = ReaderState.READING_HEADER;
+  private currentHeader: Sv2FrameHeader | null = null;
+
+  constructor(decryptFn: DecryptFn | null) {
+    this.decryptFn = decryptFn;
+  }
+
+  /** Switch to encrypted mode (after handshake completes). */
+  setDecryptFn(fn: DecryptFn): void {
+    this.decryptFn = fn;
+  }
+
+  /** Expected header size: 22 bytes encrypted, 6 bytes plaintext. */
+  private get headerSize(): number {
+    return this.decryptFn ? SV2_ENCRYPTED_HEADER_SIZE : SV2_HEADER_SIZE;
+  }
+
+  /**
+   * Feed incoming TCP data and return any complete frames.
+   */
+  feed(data: Buffer): ParsedFrame[] {
+    this.buf = this.buf.length === 0 ? data : Buffer.concat([this.buf, data]);
+    const frames: ParsedFrame[] = [];
+
+    while (true) {
+      if (this.state === ReaderState.READING_HEADER) {
+        if (this.buf.length < this.headerSize) break;
+
+        let headerBytes: Buffer;
+        if (this.decryptFn) {
+          headerBytes = this.decryptFn(this.buf.subarray(0, SV2_ENCRYPTED_HEADER_SIZE));
+        } else {
+          headerBytes = this.buf.subarray(0, SV2_HEADER_SIZE);
+        }
+
+        this.currentHeader = decodeFrameHeader(headerBytes);
+        this.buf = Buffer.from(this.buf.subarray(this.headerSize));
+        this.state = ReaderState.READING_PAYLOAD;
+      }
+
+      if (this.state === ReaderState.READING_PAYLOAD) {
+        const payloadWireLen = this.decryptFn
+          ? plaintextToCiphertextLength(this.currentHeader!.msgLength)
+          : this.currentHeader!.msgLength;
+
+        if (this.buf.length < payloadWireLen) break;
+
+        let payload: Buffer;
+        if (this.decryptFn && payloadWireLen > 0) {
+          payload = this.decryptPayloadChunks(this.buf.subarray(0, payloadWireLen));
+        } else {
+          payload = Buffer.from(this.buf.subarray(0, payloadWireLen));
+        }
+
+        frames.push({ header: this.currentHeader!, payload });
+        this.buf = Buffer.from(this.buf.subarray(payloadWireLen));
+        this.currentHeader = null;
+        this.state = ReaderState.READING_HEADER;
+      }
+    }
+
+    return frames;
+  }
+
+  private decryptPayloadChunks(ciphertext: Buffer): Buffer {
+    const chunkSize = SV2_MAX_PLAINTEXT_CHUNK + SV2_MAC_SIZE;
+    const parts: Buffer[] = [];
+    let offset = 0;
+
+    while (offset < ciphertext.length) {
+      const remaining = ciphertext.length - offset;
+      const thisChunkLen = Math.min(remaining, chunkSize);
+      const chunk = ciphertext.subarray(offset, offset + thisChunkLen);
+      parts.push(this.decryptFn!(Buffer.from(chunk)));
+      offset += thisChunkLen;
+    }
+
+    return Buffer.concat(parts);
+  }
+}
+
+// ── Frame Writer (serialization + encryption) ───────────────────────
+
+export class Sv2FrameWriter {
+  private encryptFn: EncryptFn | null;
+
+  constructor(encryptFn: EncryptFn | null) {
+    this.encryptFn = encryptFn;
+  }
+
+  /** Switch to encrypted mode (after handshake completes). */
+  setEncryptFn(fn: EncryptFn): void {
+    this.encryptFn = fn;
+  }
+
+  /**
+   * Encode a complete frame (header + payload) ready for the wire.
+   */
+  writeFrame(header: Sv2FrameHeader, payload: Buffer): Buffer {
+    const headerBuf = encodeFrameHeader(header);
+
+    if (!this.encryptFn) {
+      return Buffer.concat([headerBuf, payload]);
+    }
+
+    // Encrypt header
+    const encHeader = this.encryptFn(headerBuf);
+
+    // Encrypt payload in chunks
+    const parts: Buffer[] = [encHeader];
+    let offset = 0;
+
+    while (offset < payload.length) {
+      const remaining = payload.length - offset;
+      const chunkLen = Math.min(remaining, SV2_MAX_PLAINTEXT_CHUNK);
+      const chunk = payload.subarray(offset, offset + chunkLen);
+      parts.push(this.encryptFn(Buffer.from(chunk)));
+      offset += chunkLen;
+    }
+
+    return Buffer.concat(parts);
+  }
+}

src/models/sv2/sv2-jdp-messages.spec.ts

@@ -0,0 +1,312 @@
+import { BufferReader } from './sv2-binary-codec';
+import {
+  Sv2AllocateMiningJobToken,
+  serializeAllocateMiningJobToken,
+  deserializeAllocateMiningJobToken,
+  Sv2AllocateMiningJobTokenSuccess,
+  serializeAllocateMiningJobTokenSuccess,
+  deserializeAllocateMiningJobTokenSuccess,
+  Sv2DeclareMiningJob,
+  serializeDeclareMiningJob,
+  deserializeDeclareMiningJob,
+  Sv2DeclareMiningJobSuccess,
+  serializeDeclareMiningJobSuccess,
+  deserializeDeclareMiningJobSuccess,
+  Sv2DeclareMiningJobError,
+  serializeDeclareMiningJobError,
+  deserializeDeclareMiningJobError,
+  Sv2ProvideMissingTransactions,
+  serializeProvideMissingTransactions,
+  deserializeProvideMissingTransactions,
+  Sv2ProvideMissingTransactionsSuccess,
+  serializeProvideMissingTransactionsSuccess,
+  deserializeProvideMissingTransactionsSuccess,
+  Sv2SetCustomMiningJob,
+  serializeSetCustomMiningJob,
+  deserializeSetCustomMiningJob,
+  Sv2SetCustomMiningJobSuccess,
+  serializeSetCustomMiningJobSuccess,
+  deserializeSetCustomMiningJobSuccess,
+  Sv2SetCustomMiningJobError,
+  serializeSetCustomMiningJobError,
+  deserializeSetCustomMiningJobError,
+  Sv2PushSolution,
+  serializePushSolution,
+  deserializePushSolution,
+} from './sv2-jdp-messages';
+
+function roundTrip<T>(
+  msg: T,
+  serialize: (m: T) => Buffer,
+  deserialize: (r: BufferReader) => T,
+): T {
+  const buf = serialize(msg);
+  return deserialize(new BufferReader(buf));
+}
+
+describe('SV2 JDP Messages', () => {
+  it('AllocateMiningJobToken round-trips', () => {
+    const msg: Sv2AllocateMiningJobToken = {
+      userIdentifier: 'miner-001',
+      requestId: 1,
+    };
+    const result = roundTrip(msg, serializeAllocateMiningJobToken, deserializeAllocateMiningJobToken);
+    expect(result.userIdentifier).toBe(msg.userIdentifier);
+    expect(result.requestId).toBe(msg.requestId);
+  });
+
+  it('AllocateMiningJobTokenSuccess round-trips', () => {
+    const msg: Sv2AllocateMiningJobTokenSuccess = {
+      requestId: 1,
+      miningJobToken: Buffer.from('token123', 'utf8'),
+      coinbaseOutputs: Buffer.from('cafebabe', 'hex'),
+    };
+    const result = roundTrip(msg, serializeAllocateMiningJobTokenSuccess, deserializeAllocateMiningJobTokenSuccess);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.miningJobToken).toEqual(msg.miningJobToken);
+    expect(result.coinbaseOutputs).toEqual(msg.coinbaseOutputs);
+  });
+
+  it('AllocateMiningJobTokenSuccess with empty coinbaseOutputs', () => {
+    const msg: Sv2AllocateMiningJobTokenSuccess = {
+      requestId: 42,
+      miningJobToken: Buffer.from('tok'),
+      coinbaseOutputs: Buffer.alloc(0),
+    };
+    const result = roundTrip(msg, serializeAllocateMiningJobTokenSuccess, deserializeAllocateMiningJobTokenSuccess);
+    expect(result.coinbaseOutputs.length).toBe(0);
+  });
+
+  it('DeclareMiningJob round-trips', () => {
+    const wtxid1 = Buffer.alloc(32, 0x11);
+    const wtxid2 = Buffer.alloc(32, 0x22);
+    const msg: Sv2DeclareMiningJob = {
+      requestId: 42,
+      miningJobToken: Buffer.from('mytoken'),
+      version: 0x20000000,
+      coinbaseTxPrefix: Buffer.from('deadbeef', 'hex'),
+      coinbaseTxSuffix: Buffer.from('cafebabe', 'hex'),
+      wtxidList: [wtxid1, wtxid2],
+      excessData: Buffer.from('extra'),
+    };
+    const result = roundTrip(msg, serializeDeclareMiningJob, deserializeDeclareMiningJob);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.miningJobToken).toEqual(msg.miningJobToken);
+    expect(result.version).toBe(msg.version);
+    expect(result.coinbaseTxPrefix).toEqual(msg.coinbaseTxPrefix);
+    expect(result.coinbaseTxSuffix).toEqual(msg.coinbaseTxSuffix);
+    expect(result.wtxidList).toHaveLength(2);
+    expect(result.wtxidList[0]).toEqual(wtxid1);
+    expect(result.wtxidList[1]).toEqual(wtxid2);
+    expect(result.excessData).toEqual(msg.excessData);
+  });
+
+  it('DeclareMiningJob with empty tx list', () => {
+    const msg: Sv2DeclareMiningJob = {
+      requestId: 1,
+      miningJobToken: Buffer.alloc(0),
+      version: 0x20000000,
+      coinbaseTxPrefix: Buffer.alloc(0),
+      coinbaseTxSuffix: Buffer.alloc(0),
+      wtxidList: [],
+      excessData: Buffer.alloc(0),
+    };
+    const result = roundTrip(msg, serializeDeclareMiningJob, deserializeDeclareMiningJob);
+    expect(result.wtxidList).toHaveLength(0);
+  });
+
+  it('DeclareMiningJobSuccess round-trips', () => {
+    const msg: Sv2DeclareMiningJobSuccess = {
+      requestId: 42,
+      newMiningJobToken: Buffer.from('newtoken'),
+    };
+    const result = roundTrip(msg, serializeDeclareMiningJobSuccess, deserializeDeclareMiningJobSuccess);
+    expect(result).toEqual(msg);
+  });
+
+  it('DeclareMiningJobError round-trips', () => {
+    const msg: Sv2DeclareMiningJobError = {
+      requestId: 42,
+      errorCode: 'invalid-mining-job-token',
+      errorDetails: Buffer.from('Token expired'),
+    };
+    const result = roundTrip(msg, serializeDeclareMiningJobError, deserializeDeclareMiningJobError);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.errorCode).toBe(msg.errorCode);
+    expect(result.errorDetails).toEqual(msg.errorDetails);
+  });
+
+  it('ProvideMissingTransactions round-trips', () => {
+    const msg: Sv2ProvideMissingTransactions = {
+      requestId: 7,
+      unknownTxPositionList: [0, 3, 7, 15],
+    };
+    const result = roundTrip(msg, serializeProvideMissingTransactions, deserializeProvideMissingTransactions);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.unknownTxPositionList).toEqual([0, 3, 7, 15]);
+  });
+
+  it('ProvideMissingTransactionsSuccess round-trips (B0_16M inner type)', () => {
+    const tx1 = Buffer.from('0100000001', 'hex');
+    const tx2 = Buffer.from('0200000002abcdef', 'hex');
+    const msg: Sv2ProvideMissingTransactionsSuccess = {
+      requestId: 7,
+      transactionList: [tx1, tx2],
+    };
+    const result = roundTrip(msg, serializeProvideMissingTransactionsSuccess, deserializeProvideMissingTransactionsSuccess);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.transactionList).toHaveLength(2);
+    expect(result.transactionList[0]).toEqual(tx1);
+    expect(result.transactionList[1]).toEqual(tx2);
+  });
+
+  it('ProvideMissingTransactionsSuccess with large transaction (>64KB)', () => {
+    const largeTx = Buffer.alloc(100000, 0xab); // 100KB > 64KB limit of B0_64K
+    const msg: Sv2ProvideMissingTransactionsSuccess = {
+      requestId: 1,
+      transactionList: [largeTx],
+    };
+    const result = roundTrip(msg, serializeProvideMissingTransactionsSuccess, deserializeProvideMissingTransactionsSuccess);
+    expect(result.transactionList[0].length).toBe(100000);
+    expect(result.transactionList[0]).toEqual(largeTx);
+  });
+
+  it('SetCustomMiningJob round-trips', () => {
+    const hash1 = Buffer.alloc(32, 0xaa);
+    const msg: Sv2SetCustomMiningJob = {
+      channelId: 1,
+      requestId: 100,
+      token: Buffer.from('mytoken'),
+      version: 0x20000000,
+      prevHash: Buffer.alloc(32, 0xbb),
+      minNtime: 1700000000,
+      nBits: 0x1d00ffff,
+      coinbaseTxVersion: 2,
+      coinbasePrefix: Buffer.from('deadbeef', 'hex'),
+      coinbaseTxInputNSequence: 0xffffffff,
+      coinbaseTxOutputs: Buffer.from('outputs'),
+      coinbaseTxLocktime: 0,
+      merklePath: [hash1],
+    };
+    const result = roundTrip(msg, serializeSetCustomMiningJob, deserializeSetCustomMiningJob);
+    expect(result.channelId).toBe(msg.channelId);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.token).toEqual(msg.token);
+    expect(result.version).toBe(msg.version);
+    expect(result.prevHash).toEqual(msg.prevHash);
+    expect(result.minNtime).toBe(msg.minNtime);
+    expect(result.nBits).toBe(msg.nBits);
+    expect(result.coinbaseTxVersion).toBe(msg.coinbaseTxVersion);
+    expect(result.coinbasePrefix).toEqual(msg.coinbasePrefix);
+    expect(result.coinbaseTxInputNSequence).toBe(msg.coinbaseTxInputNSequence);
+    expect(result.coinbaseTxOutputs).toEqual(msg.coinbaseTxOutputs);
+    expect(result.coinbaseTxLocktime).toBe(msg.coinbaseTxLocktime);
+    expect(result.merklePath).toHaveLength(1);
+    expect(result.merklePath[0]).toEqual(hash1);
+  });
+
+  it('SetCustomMiningJobSuccess round-trips', () => {
+    const msg: Sv2SetCustomMiningJobSuccess = {
+      channelId: 1,
+      requestId: 100,
+      jobId: 42,
+    };
+    const result = roundTrip(msg, serializeSetCustomMiningJobSuccess, deserializeSetCustomMiningJobSuccess);
+    expect(result).toEqual(msg);
+  });
+
+  it('SetCustomMiningJobError round-trips', () => {
+    const msg: Sv2SetCustomMiningJobError = {
+      channelId: 1,
+      requestId: 100,
+      errorCode: 'invalid-mining-job-token',
+    };
+    const result = roundTrip(msg, serializeSetCustomMiningJobError, deserializeSetCustomMiningJobError);
+    expect(result).toEqual(msg);
+  });
+
+  it('serialized DeclareMiningJob has correct structure', () => {
+    const msg: Sv2DeclareMiningJob = {
+      requestId: 1,
+      miningJobToken: Buffer.from([0xab]),
+      version: 2,
+      coinbaseTxPrefix: Buffer.alloc(0),
+      coinbaseTxSuffix: Buffer.alloc(0),
+      wtxidList: [],
+      excessData: Buffer.alloc(0),
+    };
+    const buf = serializeDeclareMiningJob(msg);
+    // U32(4) + B0_255(1+1) + U32(4) + B0_64K(2+0) + B0_64K(2+0) + SEQ0_64K(2+0) + B0_64K(2+0)
+    // = 4 + 2 + 4 + 2 + 2 + 2 + 2 = 18
+    expect(buf.length).toBe(18);
+  });
+
+  it('PushSolution round-trips', () => {
+    const msg: Sv2PushSolution = {
+      extranonce: Buffer.from('aabbccdd', 'hex'),
+      prevHash: Buffer.alloc(32, 0x11),
+      nonce: 0xdeadbeef,
+      ntime: 1700000000,
+      nBits: 0x1d00ffff,
+      version: 0x20000000,
+    };
+    const result = roundTrip(msg, serializePushSolution, deserializePushSolution);
+    expect(result.extranonce).toEqual(msg.extranonce);
+    expect(result.prevHash).toEqual(msg.prevHash);
+    expect(result.nonce).toBe(msg.nonce);
+    expect(result.ntime).toBe(msg.ntime);
+    expect(result.nBits).toBe(msg.nBits);
+    expect(result.version).toBe(msg.version);
+  });
+
+  it('PushSolution with empty extranonce', () => {
+    const msg: Sv2PushSolution = {
+      extranonce: Buffer.alloc(0),
+      prevHash: Buffer.alloc(32, 0xff),
+      nonce: 0,
+      ntime: 0,
+      nBits: 0,
+      version: 0,
+    };
+    const result = roundTrip(msg, serializePushSolution, deserializePushSolution);
+    expect(result.extranonce.length).toBe(0);
+    expect(result.prevHash).toEqual(msg.prevHash);
+  });
+
+  it('serialized PushSolution has correct size', () => {
+    const msg: Sv2PushSolution = {
+      extranonce: Buffer.alloc(8),
+      prevHash: Buffer.alloc(32),
+      nonce: 0,
+      ntime: 0,
+      nBits: 0,
+      version: 0,
+    };
+    const buf = serializePushSolution(msg);
+    // B0_32(1+8) + U256(32) + U32(4) + U32(4) + U32(4) + U32(4) = 57
+    expect(buf.length).toBe(57);
+  });
+
+  it('serialized SetCustomMiningJob has correct fixed overhead', () => {
+    const msg: Sv2SetCustomMiningJob = {
+      channelId: 1,
+      requestId: 2,
+      token: Buffer.alloc(0),
+      version: 0x20000000,
+      prevHash: Buffer.alloc(32),
+      minNtime: 0,
+      nBits: 0,
+      coinbaseTxVersion: 2,
+      coinbasePrefix: Buffer.alloc(0),
+      coinbaseTxInputNSequence: 0xffffffff,
+      coinbaseTxOutputs: Buffer.alloc(0),
+      coinbaseTxLocktime: 0,
+      merklePath: [],
+    };
+    const buf = serializeSetCustomMiningJob(msg);
+    // U32(4) + U32(4) + B0_255(1+0) + U32(4) + U256(32) + U32(4) + U32(4) + U32(4) +
+    // B0_255(1+0) + U32(4) + B0_64K(2+0) + U32(4) + SEQ0_255(1+0)
+    // = 4+4+1+4+32+4+4+4+1+4+2+4+1 = 69
+    expect(buf.length).toBe(69);
+  });
+});

src/models/sv2/sv2-jdp-messages.ts

@@ -0,0 +1,309 @@
+// ── SV2 Job Declaration Protocol (JDP) Messages ────────────────────
+// Interfaces + serialize/deserialize for all JDP message types and
+// the Mining Protocol custom job bridge messages.
+// Aligned with Rust SV2 reference (stratum/sv2/subprotocols/job-declaration).
+
+import { BufferReader, BufferWriter } from './sv2-binary-codec';
+
+// ── AllocateMiningJobToken (0x50) ──────────────────────────────────
+
+export interface Sv2AllocateMiningJobToken {
+  userIdentifier: string;  // STR0_255
+  requestId: number;       // U32
+}
+
+export function serializeAllocateMiningJobToken(msg: Sv2AllocateMiningJobToken): Buffer {
+  const w = new BufferWriter();
+  w.writeStr0_255(msg.userIdentifier);
+  w.writeU32(msg.requestId);
+  return w.toBuffer();
+}
+
+export function deserializeAllocateMiningJobToken(reader: BufferReader): Sv2AllocateMiningJobToken {
+  return {
+    userIdentifier: reader.readStr0_255(),
+    requestId: reader.readU32(),
+  };
+}
+
+// ── AllocateMiningJobToken.Success (0x51) ──────────────────────────
+
+export interface Sv2AllocateMiningJobTokenSuccess {
+  requestId: number;        // U32
+  miningJobToken: Buffer;   // B0_255
+  coinbaseOutputs: Buffer;  // B0_64K
+}
+
+export function serializeAllocateMiningJobTokenSuccess(msg: Sv2AllocateMiningJobTokenSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeB0_255(msg.miningJobToken);
+  w.writeB0_64K(msg.coinbaseOutputs);
+  return w.toBuffer();
+}
+
+export function deserializeAllocateMiningJobTokenSuccess(reader: BufferReader): Sv2AllocateMiningJobTokenSuccess {
+  return {
+    requestId: reader.readU32(),
+    miningJobToken: reader.readB0_255(),
+    coinbaseOutputs: reader.readB0_64K(),
+  };
+}
+
+// ── DeclareMiningJob (0x57) ────────────────────────────────────────
+
+export interface Sv2DeclareMiningJob {
+  requestId: number;          // U32
+  miningJobToken: Buffer;     // B0_255
+  version: number;            // U32
+  coinbaseTxPrefix: Buffer;   // B0_64K
+  coinbaseTxSuffix: Buffer;   // B0_64K
+  wtxidList: Buffer[];        // SEQ0_64K<U256>
+  excessData: Buffer;         // B0_64K
+}
+
+export function serializeDeclareMiningJob(msg: Sv2DeclareMiningJob): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeB0_255(msg.miningJobToken);
+  w.writeU32(msg.version);
+  w.writeB0_64K(msg.coinbaseTxPrefix);
+  w.writeB0_64K(msg.coinbaseTxSuffix);
+  w.writeSeq0_64K(msg.wtxidList, (writer, hash) => writer.writeU256(hash));
+  w.writeB0_64K(msg.excessData);
+  return w.toBuffer();
+}
+
+export function deserializeDeclareMiningJob(reader: BufferReader): Sv2DeclareMiningJob {
+  return {
+    requestId: reader.readU32(),
+    miningJobToken: reader.readB0_255(),
+    version: reader.readU32(),
+    coinbaseTxPrefix: reader.readB0_64K(),
+    coinbaseTxSuffix: reader.readB0_64K(),
+    wtxidList: reader.readSeq0_64K((r) => r.readU256()),
+    excessData: reader.readB0_64K(),
+  };
+}
+
+// ── DeclareMiningJob.Success (0x58) ────────────────────────────────
+
+export interface Sv2DeclareMiningJobSuccess {
+  requestId: number;           // U32
+  newMiningJobToken: Buffer;   // B0_255
+}
+
+export function serializeDeclareMiningJobSuccess(msg: Sv2DeclareMiningJobSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeB0_255(msg.newMiningJobToken);
+  return w.toBuffer();
+}
+
+export function deserializeDeclareMiningJobSuccess(reader: BufferReader): Sv2DeclareMiningJobSuccess {
+  return {
+    requestId: reader.readU32(),
+    newMiningJobToken: reader.readB0_255(),
+  };
+}
+
+// ── DeclareMiningJob.Error (0x59) ──────────────────────────────────
+
+export interface Sv2DeclareMiningJobError {
+  requestId: number;     // U32
+  errorCode: string;     // STR0_255
+  errorDetails: Buffer;  // B0_64K
+}
+
+export function serializeDeclareMiningJobError(msg: Sv2DeclareMiningJobError): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeStr0_255(msg.errorCode);
+  w.writeB0_64K(msg.errorDetails);
+  return w.toBuffer();
+}
+
+export function deserializeDeclareMiningJobError(reader: BufferReader): Sv2DeclareMiningJobError {
+  return {
+    requestId: reader.readU32(),
+    errorCode: reader.readStr0_255(),
+    errorDetails: reader.readB0_64K(),
+  };
+}
+
+// ── ProvideMissingTransactions (0x55) ──────────────────────────────
+
+export interface Sv2ProvideMissingTransactions {
+  requestId: number;              // U32
+  unknownTxPositionList: number[]; // SEQ0_64K<U16>
+}
+
+export function serializeProvideMissingTransactions(msg: Sv2ProvideMissingTransactions): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeSeq0_64K(msg.unknownTxPositionList, (writer, pos) => writer.writeU16(pos));
+  return w.toBuffer();
+}
+
+export function deserializeProvideMissingTransactions(reader: BufferReader): Sv2ProvideMissingTransactions {
+  return {
+    requestId: reader.readU32(),
+    unknownTxPositionList: reader.readSeq0_64K((r) => r.readU16()),
+  };
+}
+
+// ── ProvideMissingTransactions.Success (0x56) ──────────────────────
+
+export interface Sv2ProvideMissingTransactionsSuccess {
+  requestId: number;          // U32
+  transactionList: Buffer[];  // SEQ0_64K<B0_16M>
+}
+
+export function serializeProvideMissingTransactionsSuccess(msg: Sv2ProvideMissingTransactionsSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeSeq0_64K(msg.transactionList, (writer, tx) => writer.writeB0_16M(tx));
+  return w.toBuffer();
+}
+
+export function deserializeProvideMissingTransactionsSuccess(reader: BufferReader): Sv2ProvideMissingTransactionsSuccess {
+  return {
+    requestId: reader.readU32(),
+    transactionList: reader.readSeq0_64K((r) => r.readB0_16M()),
+  };
+}
+
+// ── PushSolution (0x60) ────────────────────────────────────────
+
+export interface Sv2PushSolution {
+  extranonce: Buffer;  // B0_32
+  prevHash: Buffer;    // U256
+  nonce: number;       // U32
+  ntime: number;       // U32
+  nBits: number;       // U32
+  version: number;     // U32
+}
+
+export function serializePushSolution(msg: Sv2PushSolution): Buffer {
+  const w = new BufferWriter();
+  w.writeB0_32(msg.extranonce);
+  w.writeU256(msg.prevHash);
+  w.writeU32(msg.nonce);
+  w.writeU32(msg.ntime);
+  w.writeU32(msg.nBits);
+  w.writeU32(msg.version);
+  return w.toBuffer();
+}
+
+export function deserializePushSolution(reader: BufferReader): Sv2PushSolution {
+  return {
+    extranonce: reader.readB0_32(),
+    prevHash: reader.readU256(),
+    nonce: reader.readU32(),
+    ntime: reader.readU32(),
+    nBits: reader.readU32(),
+    version: reader.readU32(),
+  };
+}
+
+// ── SetCustomMiningJob (0x22) ──────────────────────────────────────
+
+export interface Sv2SetCustomMiningJob {
+  channelId: number;               // U32
+  requestId: number;               // U32
+  token: Buffer;                   // B0_255
+  version: number;                 // U32
+  prevHash: Buffer;                // U256
+  minNtime: number;                // U32
+  nBits: number;                   // U32
+  coinbaseTxVersion: number;       // U32
+  coinbasePrefix: Buffer;          // B0_255
+  coinbaseTxInputNSequence: number; // U32
+  coinbaseTxOutputs: Buffer;       // B0_64K
+  coinbaseTxLocktime: number;      // U32
+  merklePath: Buffer[];            // SEQ0_255<U256>
+}
+
+export function serializeSetCustomMiningJob(msg: Sv2SetCustomMiningJob): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.requestId);
+  w.writeB0_255(msg.token);
+  w.writeU32(msg.version);
+  w.writeU256(msg.prevHash);
+  w.writeU32(msg.minNtime);
+  w.writeU32(msg.nBits);
+  w.writeU32(msg.coinbaseTxVersion);
+  w.writeB0_255(msg.coinbasePrefix);
+  w.writeU32(msg.coinbaseTxInputNSequence);
+  w.writeB0_64K(msg.coinbaseTxOutputs);
+  w.writeU32(msg.coinbaseTxLocktime);
+  w.writeSeq0_255(msg.merklePath, (writer, hash) => writer.writeU256(hash));
+  return w.toBuffer();
+}
+
+export function deserializeSetCustomMiningJob(reader: BufferReader): Sv2SetCustomMiningJob {
+  return {
+    channelId: reader.readU32(),
+    requestId: reader.readU32(),
+    token: reader.readB0_255(),
+    version: reader.readU32(),
+    prevHash: reader.readU256(),
+    minNtime: reader.readU32(),
+    nBits: reader.readU32(),
+    coinbaseTxVersion: reader.readU32(),
+    coinbasePrefix: reader.readB0_255(),
+    coinbaseTxInputNSequence: reader.readU32(),
+    coinbaseTxOutputs: reader.readB0_64K(),
+    coinbaseTxLocktime: reader.readU32(),
+    merklePath: reader.readSeq0_255((r) => r.readU256()),
+  };
+}
+
+// ── SetCustomMiningJob.Success (0x23) ──────────────────────────────
+
+export interface Sv2SetCustomMiningJobSuccess {
+  channelId: number; // U32
+  requestId: number; // U32
+  jobId: number;     // U32
+}
+
+export function serializeSetCustomMiningJobSuccess(msg: Sv2SetCustomMiningJobSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.requestId);
+  w.writeU32(msg.jobId);
+  return w.toBuffer();
+}
+
+export function deserializeSetCustomMiningJobSuccess(reader: BufferReader): Sv2SetCustomMiningJobSuccess {
+  return {
+    channelId: reader.readU32(),
+    requestId: reader.readU32(),
+    jobId: reader.readU32(),
+  };
+}
+
+// ── SetCustomMiningJob.Error (0x24) ────────────────────────────────
+
+export interface Sv2SetCustomMiningJobError {
+  channelId: number;  // U32
+  requestId: number;  // U32
+  errorCode: string;  // STR0_255
+}
+
+export function serializeSetCustomMiningJobError(msg: Sv2SetCustomMiningJobError): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.requestId);
+  w.writeStr0_255(msg.errorCode);
+  return w.toBuffer();
+}
+
+export function deserializeSetCustomMiningJobError(reader: BufferReader): Sv2SetCustomMiningJobError {
+  return {
+    channelId: reader.readU32(),
+    requestId: reader.readU32(),
+    errorCode: reader.readStr0_255(),
+  };
+}

src/models/sv2/sv2-messages.spec.ts

@@ -0,0 +1,250 @@
+import { BufferReader } from './sv2-binary-codec';
+import {
+  Sv2SetupConnection, serializeSetupConnection, deserializeSetupConnection,
+  Sv2SetupConnectionSuccess, serializeSetupConnectionSuccess, deserializeSetupConnectionSuccess,
+  Sv2SetupConnectionError, serializeSetupConnectionError, deserializeSetupConnectionError,
+  Sv2ChannelEndpointChanged, serializeChannelEndpointChanged, deserializeChannelEndpointChanged,
+  Sv2OpenStandardMiningChannel, serializeOpenStandardMiningChannel, deserializeOpenStandardMiningChannel,
+  Sv2OpenStandardMiningChannelSuccess, serializeOpenStandardMiningChannelSuccess, deserializeOpenStandardMiningChannelSuccess,
+  Sv2NewMiningJob, serializeNewMiningJob, deserializeNewMiningJob,
+  Sv2SetNewPrevHash, serializeSetNewPrevHash, deserializeSetNewPrevHash,
+  Sv2SetTarget, serializeSetTarget, deserializeSetTarget,
+  Sv2SubmitSharesStandard, serializeSubmitSharesStandard, deserializeSubmitSharesStandard,
+  Sv2SubmitSharesSuccess, serializeSubmitSharesSuccess, deserializeSubmitSharesSuccess,
+  Sv2SubmitSharesError, serializeSubmitSharesError, deserializeSubmitSharesError,
+  Sv2CloseChannel, serializeCloseChannel, deserializeCloseChannel,
+  Sv2UpdateChannel, serializeUpdateChannel, deserializeUpdateChannel,
+  Sv2UpdateChannelError, serializeUpdateChannelError, deserializeUpdateChannelError,
+  Sv2Reconnect, serializeReconnect, deserializeReconnect,
+} from './sv2-messages';
+
+function roundTrip<T>(
+  msg: T,
+  serialize: (m: T) => Buffer,
+  deserialize: (r: BufferReader) => T,
+): T {
+  const buf = serialize(msg);
+  return deserialize(new BufferReader(buf));
+}
+
+describe('SV2 Messages', () => {
+  it('SetupConnection round-trips', () => {
+    const msg: Sv2SetupConnection = {
+      protocol: 0,
+      minVersion: 2,
+      maxVersion: 2,
+      flags: 0x07,
+      endpoint_host: 'pool.example.com',
+      endpoint_port: 3333,
+      vendor: 'TestMiner',
+      hardwareVersion: '1.0',
+      firmwareVersion: '2.1',
+      deviceId: 'device-001',
+    };
+    const result = roundTrip(msg, serializeSetupConnection, deserializeSetupConnection);
+    expect(result).toEqual(msg);
+  });
+
+  it('SetupConnectionSuccess round-trips', () => {
+    const msg: Sv2SetupConnectionSuccess = {
+      usedVersion: 2,
+      flags: 0x05,
+    };
+    const result = roundTrip(msg, serializeSetupConnectionSuccess, deserializeSetupConnectionSuccess);
+    expect(result).toEqual(msg);
+  });
+
+  it('SetupConnectionError round-trips', () => {
+    const msg: Sv2SetupConnectionError = {
+      flags: 0x00,
+      errorCode: 'unsupported-feature-flags',
+    };
+    const result = roundTrip(msg, serializeSetupConnectionError, deserializeSetupConnectionError);
+    expect(result).toEqual(msg);
+  });
+
+  it('ChannelEndpointChanged round-trips', () => {
+    const msg: Sv2ChannelEndpointChanged = {
+      channelId: 7,
+    };
+    const result = roundTrip(msg, serializeChannelEndpointChanged, deserializeChannelEndpointChanged);
+    expect(result).toEqual(msg);
+  });
+
+  it('OpenStandardMiningChannel round-trips', () => {
+    const maxTarget = Buffer.alloc(32, 0x00);
+    maxTarget[0] = 0xff;
+    maxTarget[28] = 0x1d;
+    const msg: Sv2OpenStandardMiningChannel = {
+      requestId: 1,
+      user_identity: 'worker1',
+      nominalHashRate: 1000000.0,
+      maxTarget,
+    };
+    const result = roundTrip(msg, serializeOpenStandardMiningChannel, deserializeOpenStandardMiningChannel);
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.user_identity).toBe(msg.user_identity);
+    expect(result.nominalHashRate).toBeCloseTo(msg.nominalHashRate, 0);
+    expect(result.maxTarget).toEqual(msg.maxTarget);
+  });
+
+  it('OpenStandardMiningChannelSuccess round-trips', () => {
+    const target = Buffer.alloc(32);
+    target[0] = 0xff;
+    target[31] = 0x01;
+    const msg: Sv2OpenStandardMiningChannelSuccess = {
+      requestId: 1,
+      channelId: 42,
+      target,
+      extranonce_prefix: Buffer.from([0x01, 0x02, 0x03]),
+      groupChannelId: 0,
+    };
+    const result = roundTrip(
+      msg,
+      serializeOpenStandardMiningChannelSuccess,
+      deserializeOpenStandardMiningChannelSuccess,
+    );
+    expect(result.requestId).toBe(msg.requestId);
+    expect(result.channelId).toBe(msg.channelId);
+    expect(result.target).toEqual(msg.target);
+    expect(result.extranonce_prefix).toEqual(msg.extranonce_prefix);
+    expect(result.groupChannelId).toBe(msg.groupChannelId);
+  });
+
+  it('NewMiningJob round-trips', () => {
+    const merkleRoot = Buffer.alloc(32, 0xab);
+    const msg: Sv2NewMiningJob = {
+      channelId: 1,
+      jobId: 100,
+      minNtime: null, // Sv2Option<U32>: null = future job
+      version: 0x20000000,
+      merkleRoot,
+    };
+    const result = roundTrip(msg, serializeNewMiningJob, deserializeNewMiningJob);
+    expect(result).toEqual(msg);
+  });
+
+  it('NewMiningJob round-trips with minNtime value', () => {
+    const merkleRoot = Buffer.alloc(32, 0xab);
+    const msg: Sv2NewMiningJob = {
+      channelId: 1,
+      jobId: 101,
+      minNtime: 1700000000, // Sv2Option<U32>: Some(timestamp) = ready to mine
+      version: 0x20000000,
+      merkleRoot,
+    };
+    const result = roundTrip(msg, serializeNewMiningJob, deserializeNewMiningJob);
+    expect(result).toEqual(msg);
+  });
+
+  it('SetNewPrevHash round-trips', () => {
+    const prevHash = Buffer.alloc(32, 0xcd);
+    const msg: Sv2SetNewPrevHash = {
+      channelId: 1,
+      jobId: 100,
+      prevHash,
+      minNtime: 1700000000,
+      nBits: 0x1d00ffff,
+    };
+    const result = roundTrip(msg, serializeSetNewPrevHash, deserializeSetNewPrevHash);
+    expect(result).toEqual(msg);
+  });
+
+  it('SetTarget round-trips', () => {
+    const maxTarget = Buffer.alloc(32, 0x00);
+    maxTarget[0] = 0xff;
+    const msg: Sv2SetTarget = {
+      channelId: 5,
+      maxTarget,
+    };
+    const result = roundTrip(msg, serializeSetTarget, deserializeSetTarget);
+    expect(result).toEqual(msg);
+  });
+
+  it('SubmitSharesStandard round-trips', () => {
+    const msg: Sv2SubmitSharesStandard = {
+      channelId: 1,
+      sequenceNumber: 42,
+      jobId: 100,
+      nonce: 0xdeadbeef,
+      ntime: 1700000000,
+      version: 0x20000000,
+    };
+    const result = roundTrip(msg, serializeSubmitSharesStandard, deserializeSubmitSharesStandard);
+    expect(result).toEqual(msg);
+  });
+
+  it('SubmitSharesSuccess round-trips', () => {
+    const msg: Sv2SubmitSharesSuccess = {
+      channelId: 1,
+      lastSequenceNumber: 42,
+      newSubmitsAcceptedCount: 10,
+      newSharesSum: 123456789012345n,
+    };
+    const result = roundTrip(msg, serializeSubmitSharesSuccess, deserializeSubmitSharesSuccess);
+    expect(result).toEqual(msg);
+  });
+
+  it('SubmitSharesError round-trips', () => {
+    const msg: Sv2SubmitSharesError = {
+      channelId: 1,
+      sequenceNumber: 42,
+      errorCode: 'stale-share',
+    };
+    const result = roundTrip(msg, serializeSubmitSharesError, deserializeSubmitSharesError);
+    expect(result).toEqual(msg);
+  });
+
+  it('CloseChannel round-trips', () => {
+    const msg: Sv2CloseChannel = {
+      channelId: 7,
+      reasonCode: 'client-disconnect',
+    };
+    const result = roundTrip(msg, serializeCloseChannel, deserializeCloseChannel);
+    expect(result).toEqual(msg);
+  });
+
+  it('UpdateChannel round-trips', () => {
+    const maximumTarget = Buffer.alloc(32, 0x00);
+    maximumTarget[0] = 0xff;
+    const msg: Sv2UpdateChannel = {
+      channelId: 3,
+      nominalHashRate: 500000.0,
+      maximumTarget,
+    };
+    const result = roundTrip(msg, serializeUpdateChannel, deserializeUpdateChannel);
+    expect(result.channelId).toBe(msg.channelId);
+    expect(result.nominalHashRate).toBeCloseTo(msg.nominalHashRate, 0);
+    expect(result.maximumTarget).toEqual(msg.maximumTarget);
+  });
+
+  it('UpdateChannelError round-trips', () => {
+    const msg: Sv2UpdateChannelError = {
+      channelId: 3,
+      errorCode: 'invalid-channel',
+    };
+    const result = roundTrip(msg, serializeUpdateChannelError, deserializeUpdateChannelError);
+    expect(result).toEqual(msg);
+  });
+
+  it('Reconnect round-trips', () => {
+    const msg: Sv2Reconnect = {
+      newHost: 'pool2.example.com',
+      newPort: 3334,
+    };
+    const result = roundTrip(msg, serializeReconnect, deserializeReconnect);
+    expect(result).toEqual(msg);
+  });
+
+  it('serialized bytes match expected layout (SetupConnectionSuccess)', () => {
+    const msg: Sv2SetupConnectionSuccess = {
+      usedVersion: 2,
+      flags: 0x01,
+    };
+    const buf = serializeSetupConnectionSuccess(msg);
+    // U16 LE(2) + U32 LE(1) = 6 bytes
+    expect(buf.length).toBe(6);
+    expect(buf.readUInt16LE(0)).toBe(2);
+    expect(buf.readUInt32LE(2)).toBe(1);
+  });
+});

src/models/sv2/sv2-messages.ts

@@ -0,0 +1,478 @@
+// ── SV2 Mining Protocol Messages ────────────────────────────────────
+// Interfaces + serialize/deserialize for each message needed for
+// standard mining channels.
+
+import { BufferReader, BufferWriter } from './sv2-binary-codec';
+
+// ── SetupConnection (0x00) ──────────────────────────────────────────
+
+export interface Sv2SetupConnection {
+  protocol: number; // U8 (0 = Mining, 1 = Job Declaration, 2 = Template Distribution)
+  minVersion: number; // U16
+  maxVersion: number; // U16
+  flags: number; // U32
+  endpoint_host: string; // STR0_255
+  endpoint_port: number; // U16
+  vendor: string; // STR0_255
+  hardwareVersion: string; // STR0_255
+  firmwareVersion: string; // STR0_255
+  deviceId: string; // STR0_255
+}
+
+export function serializeSetupConnection(msg: Sv2SetupConnection): Buffer {
+  const w = new BufferWriter();
+  w.writeU8(msg.protocol);
+  w.writeU16(msg.minVersion);
+  w.writeU16(msg.maxVersion);
+  w.writeU32(msg.flags);
+  w.writeStr0_255(msg.endpoint_host);
+  w.writeU16(msg.endpoint_port);
+  w.writeStr0_255(msg.vendor);
+  w.writeStr0_255(msg.hardwareVersion);
+  w.writeStr0_255(msg.firmwareVersion);
+  w.writeStr0_255(msg.deviceId);
+  return w.toBuffer();
+}
+
+export function deserializeSetupConnection(reader: BufferReader): Sv2SetupConnection {
+  return {
+    protocol: reader.readU8(),
+    minVersion: reader.readU16(),
+    maxVersion: reader.readU16(),
+    flags: reader.readU32(),
+    endpoint_host: reader.readStr0_255(),
+    endpoint_port: reader.readU16(),
+    vendor: reader.readStr0_255(),
+    hardwareVersion: reader.readStr0_255(),
+    firmwareVersion: reader.readStr0_255(),
+    deviceId: reader.readStr0_255(),
+  };
+}
+
+// ── SetupConnectionSuccess (0x01) ───────────────────────────────────
+
+export interface Sv2SetupConnectionSuccess {
+  usedVersion: number; // U16
+  flags: number; // U32
+}
+
+export function serializeSetupConnectionSuccess(msg: Sv2SetupConnectionSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU16(msg.usedVersion);
+  w.writeU32(msg.flags);
+  return w.toBuffer();
+}
+
+export function deserializeSetupConnectionSuccess(reader: BufferReader): Sv2SetupConnectionSuccess {
+  return {
+    usedVersion: reader.readU16(),
+    flags: reader.readU32(),
+  };
+}
+
+// ── SetupConnectionError (0x02) ─────────────────────────────────────
+
+export interface Sv2SetupConnectionError {
+  flags: number; // U32
+  errorCode: string; // STR0_255
+}
+
+export function serializeSetupConnectionError(msg: Sv2SetupConnectionError): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.flags);
+  w.writeStr0_255(msg.errorCode);
+  return w.toBuffer();
+}
+
+export function deserializeSetupConnectionError(reader: BufferReader): Sv2SetupConnectionError {
+  return {
+    flags: reader.readU32(),
+    errorCode: reader.readStr0_255(),
+  };
+}
+
+// ── ChannelEndpointChanged (0x03) ───────────────────────────────────
+
+export interface Sv2ChannelEndpointChanged {
+  channelId: number; // U32
+}
+
+export function serializeChannelEndpointChanged(msg: Sv2ChannelEndpointChanged): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  return w.toBuffer();
+}
+
+export function deserializeChannelEndpointChanged(reader: BufferReader): Sv2ChannelEndpointChanged {
+  return {
+    channelId: reader.readU32(),
+  };
+}
+
+// ── OpenStandardMiningChannel (0x10) ────────────────────────────────
+
+export interface Sv2OpenStandardMiningChannel {
+  requestId: number; // U32
+  user_identity: string; // STR0_255
+  nominalHashRate: number; // F32
+  maxTarget: Buffer; // U256 (32 bytes LE)
+}
+
+export function serializeOpenStandardMiningChannel(msg: Sv2OpenStandardMiningChannel): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeStr0_255(msg.user_identity);
+  w.writeF32(msg.nominalHashRate);
+  w.writeU256(msg.maxTarget);
+  return w.toBuffer();
+}
+
+export function deserializeOpenStandardMiningChannel(
+  reader: BufferReader,
+): Sv2OpenStandardMiningChannel {
+  return {
+    requestId: reader.readU32(),
+    user_identity: reader.readStr0_255(),
+    nominalHashRate: reader.readF32(),
+    maxTarget: reader.readU256(),
+  };
+}
+
+// ── OpenStandardMiningChannelSuccess (0x11) ─────────────────────────
+
+export interface Sv2OpenStandardMiningChannelSuccess {
+  requestId: number; // U32
+  channelId: number; // U32
+  target: Buffer; // U256 (32 bytes LE)
+  extranonce_prefix: Buffer; // B0_32
+  groupChannelId: number; // U32
+}
+
+export function serializeOpenStandardMiningChannelSuccess(
+  msg: Sv2OpenStandardMiningChannelSuccess,
+): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeU32(msg.channelId);
+  w.writeU256(msg.target);
+  w.writeB0_32(msg.extranonce_prefix);
+  w.writeU32(msg.groupChannelId);
+  return w.toBuffer();
+}
+
+export function deserializeOpenStandardMiningChannelSuccess(
+  reader: BufferReader,
+): Sv2OpenStandardMiningChannelSuccess {
+  return {
+    requestId: reader.readU32(),
+    channelId: reader.readU32(),
+    target: reader.readU256(),
+    extranonce_prefix: reader.readB0_32(),
+    groupChannelId: reader.readU32(),
+  };
+}
+
+// ── OpenMiningChannel.Error (0x12) ──────────────────────────────────
+
+export interface Sv2OpenMiningChannelError {
+  requestId: number; // U32
+  errorCode: string; // STR0_255
+}
+
+export function serializeOpenMiningChannelError(msg: Sv2OpenMiningChannelError): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.requestId);
+  w.writeStr0_255(msg.errorCode);
+  return w.toBuffer();
+}
+
+export function deserializeOpenMiningChannelError(reader: BufferReader): Sv2OpenMiningChannelError {
+  return {
+    requestId: reader.readU32(),
+    errorCode: reader.readStr0_255(),
+  };
+}
+
+// ── NewMiningJob (0x15) ─────────────────────────────────────────────
+
+export interface Sv2NewMiningJob {
+  channelId: number; // U32
+  jobId: number; // U32
+  minNtime: number | null; // Sv2Option<U32> - null = future job, number = min ntime value
+  version: number; // U32
+  merkleRoot: Buffer; // U256 (32 bytes)
+}
+
+export function serializeNewMiningJob(msg: Sv2NewMiningJob): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.jobId);
+  w.writeOptionU32(msg.minNtime);
+  w.writeU32(msg.version);
+  w.writeU256(msg.merkleRoot);
+  return w.toBuffer();
+}
+
+export function deserializeNewMiningJob(reader: BufferReader): Sv2NewMiningJob {
+  return {
+    channelId: reader.readU32(),
+    jobId: reader.readU32(),
+    minNtime: reader.readOptionU32(),
+    version: reader.readU32(),
+    merkleRoot: reader.readU256(),
+  };
+}
+
+// ── SetNewPrevHash (0x20) ───────────────────────────────────────────
+
+export interface Sv2SetNewPrevHash {
+  channelId: number; // U32
+  jobId: number; // U32
+  prevHash: Buffer; // U256 (32 bytes)
+  minNtime: number; // U32
+  nBits: number; // U32
+}
+
+export function serializeSetNewPrevHash(msg: Sv2SetNewPrevHash): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.jobId);
+  w.writeU256(msg.prevHash);
+  w.writeU32(msg.minNtime);
+  w.writeU32(msg.nBits);
+  return w.toBuffer();
+}
+
+export function deserializeSetNewPrevHash(reader: BufferReader): Sv2SetNewPrevHash {
+  return {
+    channelId: reader.readU32(),
+    jobId: reader.readU32(),
+    prevHash: reader.readU256(),
+    minNtime: reader.readU32(),
+    nBits: reader.readU32(),
+  };
+}
+
+// ── SetTarget (0x21) ────────────────────────────────────────────────
+
+export interface Sv2SetTarget {
+  channelId: number; // U32
+  maxTarget: Buffer; // U256 (32 bytes)
+}
+
+export function serializeSetTarget(msg: Sv2SetTarget): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU256(msg.maxTarget);
+  return w.toBuffer();
+}
+
+export function deserializeSetTarget(reader: BufferReader): Sv2SetTarget {
+  return {
+    channelId: reader.readU32(),
+    maxTarget: reader.readU256(),
+  };
+}
+
+// ── SubmitSharesStandard (0x1a) ─────────────────────────────────────
+
+export interface Sv2SubmitSharesStandard {
+  channelId: number; // U32
+  sequenceNumber: number; // U32
+  jobId: number; // U32
+  nonce: number; // U32
+  ntime: number; // U32
+  version: number; // U32
+}
+
+export function serializeSubmitSharesStandard(msg: Sv2SubmitSharesStandard): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.sequenceNumber);
+  w.writeU32(msg.jobId);
+  w.writeU32(msg.nonce);
+  w.writeU32(msg.ntime);
+  w.writeU32(msg.version);
+  return w.toBuffer();
+}
+
+export function deserializeSubmitSharesStandard(reader: BufferReader): Sv2SubmitSharesStandard {
+  return {
+    channelId: reader.readU32(),
+    sequenceNumber: reader.readU32(),
+    jobId: reader.readU32(),
+    nonce: reader.readU32(),
+    ntime: reader.readU32(),
+    version: reader.readU32(),
+  };
+}
+
+// ── SubmitSharesSuccess (0x1c) ──────────────────────────────────────
+
+export interface Sv2SubmitSharesSuccess {
+  channelId: number; // U32
+  lastSequenceNumber: number; // U32
+  newSubmitsAcceptedCount: number; // U32
+  newSharesSum: bigint; // U64
+}
+
+export function serializeSubmitSharesSuccess(msg: Sv2SubmitSharesSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.lastSequenceNumber);
+  w.writeU32(msg.newSubmitsAcceptedCount);
+  w.writeU64(msg.newSharesSum);
+  return w.toBuffer();
+}
+
+export function deserializeSubmitSharesSuccess(reader: BufferReader): Sv2SubmitSharesSuccess {
+  return {
+    channelId: reader.readU32(),
+    lastSequenceNumber: reader.readU32(),
+    newSubmitsAcceptedCount: reader.readU32(),
+    newSharesSum: reader.readU64(),
+  };
+}
+
+// ── SubmitSharesError (0x1d) ────────────────────────────────────────
+
+export interface Sv2SubmitSharesError {
+  channelId: number; // U32
+  sequenceNumber: number; // U32
+  errorCode: string; // STR0_255
+}
+
+export function serializeSubmitSharesError(msg: Sv2SubmitSharesError): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeU32(msg.sequenceNumber);
+  w.writeStr0_255(msg.errorCode);
+  return w.toBuffer();
+}
+
+export function deserializeSubmitSharesError(reader: BufferReader): Sv2SubmitSharesError {
+  return {
+    channelId: reader.readU32(),
+    sequenceNumber: reader.readU32(),
+    errorCode: reader.readStr0_255(),
+  };
+}
+
+// ── CloseChannel (0x18) ─────────────────────────────────────────────
+
+export interface Sv2CloseChannel {
+  channelId: number; // U32
+  reasonCode: string; // STR0_255
+}
+
+export function serializeCloseChannel(msg: Sv2CloseChannel): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeStr0_255(msg.reasonCode);
+  return w.toBuffer();
+}
+
+export function deserializeCloseChannel(reader: BufferReader): Sv2CloseChannel {
+  return {
+    channelId: reader.readU32(),
+    reasonCode: reader.readStr0_255(),
+  };
+}
+
+// ── UpdateChannel (0x16) ────────────────────────────────────────────
+
+export interface Sv2UpdateChannel {
+  channelId: number;        // U32
+  nominalHashRate: number;  // F32
+  maximumTarget: Buffer;    // U256 (32 bytes LE)
+}
+
+export function serializeUpdateChannel(msg: Sv2UpdateChannel): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeF32(msg.nominalHashRate);
+  w.writeU256(msg.maximumTarget);
+  return w.toBuffer();
+}
+
+export function deserializeUpdateChannel(reader: BufferReader): Sv2UpdateChannel {
+  return {
+    channelId: reader.readU32(),
+    nominalHashRate: reader.readF32(),
+    maximumTarget: reader.readU256(),
+  };
+}
+
+// ── UpdateChannel.Error (0x17) ──────────────────────────────────────
+
+export interface Sv2UpdateChannelError {
+  channelId: number;  // U32
+  errorCode: string;  // STR0_255
+}
+
+export function serializeUpdateChannelError(msg: Sv2UpdateChannelError): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.channelId);
+  w.writeStr0_255(msg.errorCode);
+  return w.toBuffer();
+}
+
+export function deserializeUpdateChannelError(reader: BufferReader): Sv2UpdateChannelError {
+  return {
+    channelId: reader.readU32(),
+    errorCode: reader.readStr0_255(),
+  };
+}
+
+// ── Extension 1: Extensions Negotiation (extension_type = 0x0001) ───
+// Spec: extensions/0x0001-extensions-negotiation.md
+// RequestExtensions     msgType 0x00  (client → pool)
+// RequestExtensions.Success msgType 0x01  (pool → client)
+// RequestExtensions.Error   msgType 0x02  (pool → client)
+
+export const SV2_EXTENSION_NEGOTIATION_ID = 0x0001;
+
+export interface Sv2RequestExtensions {
+  requestId: number;            // U16
+  requestedExtensions: number[]; // SEQ0_64K[U16]
+}
+
+export function deserializeRequestExtensions(reader: BufferReader): Sv2RequestExtensions {
+  return {
+    requestId: reader.readU16(),
+    requestedExtensions: reader.readSeq0_64K((r) => r.readU16()),
+  };
+}
+
+export interface Sv2RequestExtensionsSuccess {
+  requestId: number;             // U16
+  supportedExtensions: number[]; // SEQ0_64K[U16]
+}
+
+export function serializeRequestExtensionsSuccess(msg: Sv2RequestExtensionsSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU16(msg.requestId);
+  w.writeSeq0_64K(msg.supportedExtensions, (writer, ext) => writer.writeU16(ext));
+  return w.toBuffer();
+}
+
+// ── Reconnect (0x04) ────────────────────────────────────────────────
+
+export interface Sv2Reconnect {
+  newHost: string;  // STR0_255
+  newPort: number;  // U16
+}
+
+export function serializeReconnect(msg: Sv2Reconnect): Buffer {
+  const w = new BufferWriter();
+  w.writeStr0_255(msg.newHost);
+  w.writeU16(msg.newPort);
+  return w.toBuffer();
+}
+
+export function deserializeReconnect(reader: BufferReader): Sv2Reconnect {
+  return {
+    newHost: reader.readStr0_255(),
+    newPort: reader.readU16(),
+  };
+}

src/models/sv2/sv2-noise.spec.ts

@@ -0,0 +1,500 @@
+import * as crypto from 'crypto';
+import {
+  hmacHash,
+  sha256,
+  hkdf2,
+  Sv2CipherState,
+  Sv2CipherAlgorithm,
+  Sv2NoiseSession,
+  Sv2NoiseInitiator,
+  generateServerKeypair,
+  xOnlyPubKeyFromPriv,
+  createSignatureNoiseMessage,
+  validateSignatureNoiseMessage,
+  serializeSignatureNoiseMessage,
+  deserializeSignatureNoiseMessage,
+  loadEllSwift,
+} from './sv2-noise';
+import { SV2_MAC_SIZE } from './sv2-constants';
+
+describe('SV2 Noise', () => {
+  // ── HMAC-SHA256 Test Vectors ──────────────────────────────────────
+
+  describe('HMAC-SHA256', () => {
+    it('should match known test vector (RFC 4231 test 1)', () => {
+      const key = Buffer.from('0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b', 'hex');
+      const data = Buffer.from('Hi There');
+      const expected = 'b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff7';
+      expect(hmacHash(key, data).toString('hex')).toBe(expected);
+    });
+
+    it('should match known test vector (RFC 4231 test 2)', () => {
+      const key = Buffer.from('Jefe');
+      const data = Buffer.from('what do ya want for nothing?');
+      const expected = '5bdcc146bf60754e6a042426089575c75a003f089d2739839dec58b964ec3843';
+      expect(hmacHash(key, data).toString('hex')).toBe(expected);
+    });
+  });
+
+  // ── HKDF2 ─────────────────────────────────────────────────────────
+
+  describe('HKDF2', () => {
+    it('should produce two 32-byte outputs', () => {
+      const ck = Buffer.alloc(32, 0x01);
+      const ikm = Buffer.alloc(32, 0x02);
+      const [out1, out2] = hkdf2(ck, ikm);
+      expect(out1.length).toBe(32);
+      expect(out2.length).toBe(32);
+      expect(out1.equals(out2)).toBe(false);
+    });
+
+    it('should be deterministic', () => {
+      const ck = crypto.randomBytes(32);
+      const ikm = crypto.randomBytes(32);
+      const [a1, a2] = hkdf2(ck, ikm);
+      const [b1, b2] = hkdf2(ck, ikm);
+      expect(a1.equals(b1)).toBe(true);
+      expect(a2.equals(b2)).toBe(true);
+    });
+
+    it('should work with empty IKM', () => {
+      const ck = Buffer.alloc(32, 0xaa);
+      const [out1, out2] = hkdf2(ck, Buffer.alloc(0));
+      expect(out1.length).toBe(32);
+      expect(out2.length).toBe(32);
+    });
+  });
+
+  // ── CipherState ───────────────────────────────────────────────────
+
+  describe('CipherState', () => {
+    it('should encrypt and decrypt with matching keys', () => {
+      const key = crypto.randomBytes(32);
+      const enc = new Sv2CipherState();
+      const dec = new Sv2CipherState();
+      enc.initializeKey(key);
+      dec.initializeKey(key);
+
+      const ad = Buffer.alloc(0);
+      const plaintext = Buffer.from('test message for cipher state');
+      const ciphertext = enc.encryptWithAd(ad, plaintext);
+
+      expect(ciphertext.length).toBe(plaintext.length + SV2_MAC_SIZE);
+      expect(ciphertext.subarray(0, plaintext.length).equals(plaintext)).toBe(false);
+
+      const decrypted = dec.decryptWithAd(ad, ciphertext);
+      expect(decrypted.equals(plaintext)).toBe(true);
+    });
+
+    it('should fail decryption with wrong key', () => {
+      const enc = new Sv2CipherState();
+      const dec = new Sv2CipherState();
+      enc.initializeKey(crypto.randomBytes(32));
+      dec.initializeKey(crypto.randomBytes(32));
+
+      const ct = enc.encryptWithAd(Buffer.alloc(0), Buffer.from('secret'));
+      expect(() => dec.decryptWithAd(Buffer.alloc(0), ct)).toThrow();
+    });
+
+    it('should fail decryption with wrong AD', () => {
+      const key = crypto.randomBytes(32);
+      const enc = new Sv2CipherState();
+      const dec = new Sv2CipherState();
+      enc.initializeKey(key);
+      dec.initializeKey(key);
+
+      const ct = enc.encryptWithAd(Buffer.from('ad1'), Buffer.from('data'));
+      expect(() => dec.decryptWithAd(Buffer.from('ad2'), ct)).toThrow();
+    });
+
+    it('should increment nonce (different ciphertext for same plaintext)', () => {
+      const key = crypto.randomBytes(32);
+      const enc = new Sv2CipherState();
+      enc.initializeKey(key);
+
+      const ad = Buffer.alloc(0);
+      const pt = Buffer.from('same');
+      const ct1 = enc.encryptWithAd(ad, pt);
+      const ct2 = enc.encryptWithAd(ad, pt);
+      expect(ct1.equals(ct2)).toBe(false);
+    });
+
+    it('should pass through plaintext when key is not set', () => {
+      const cs = new Sv2CipherState();
+      const ad = Buffer.alloc(0);
+      const pt = Buffer.from('hello');
+      expect(cs.encryptWithAd(ad, pt).equals(pt)).toBe(true);
+      expect(cs.decryptWithAd(ad, pt).equals(pt)).toBe(true);
+    });
+
+    it('should track hasKey', () => {
+      const cs = new Sv2CipherState();
+      expect(cs.hasKey).toBe(false);
+      cs.initializeKey(crypto.randomBytes(32));
+      expect(cs.hasKey).toBe(true);
+    });
+
+    it('should reject non-32-byte keys', () => {
+      const cs = new Sv2CipherState();
+      expect(() => cs.initializeKey(Buffer.alloc(16))).toThrow();
+    });
+
+    it('should reject ciphertext shorter than MAC', () => {
+      const cs = new Sv2CipherState();
+      cs.initializeKey(crypto.randomBytes(32));
+      expect(() => cs.decryptWithAd(Buffer.alloc(0), Buffer.alloc(10))).toThrow();
+    });
+
+    it('should handle multiple sequential encryptions and decryptions', () => {
+      const key = crypto.randomBytes(32);
+      const enc = new Sv2CipherState();
+      const dec = new Sv2CipherState();
+      enc.initializeKey(key);
+      dec.initializeKey(key);
+
+      const ad = Buffer.alloc(0);
+      for (let i = 0; i < 10; i++) {
+        const pt = Buffer.from(`message ${i}`);
+        const ct = enc.encryptWithAd(ad, pt);
+        const result = dec.decryptWithAd(ad, ct);
+        expect(result.toString()).toBe(`message ${i}`);
+      }
+    });
+  });
+
+  // ── Certificate / Signature ───────────────────────────────────────
+
+  describe('Certificate', () => {
+    it('should create and validate a signature noise message', () => {
+      const authorityPrivKey = crypto.randomBytes(32);
+      const authorityPubKey = xOnlyPubKeyFromPriv(authorityPrivKey);
+      const staticPubKeyXOnly = crypto.randomBytes(32);
+
+      const now = Math.floor(Date.now() / 1000);
+      const cert = createSignatureNoiseMessage(
+        authorityPrivKey,
+        staticPubKeyXOnly,
+        now - 3600,
+        now + 86400,
+      );
+
+      expect(cert.version).toBe(0);
+      expect(cert.signature.length).toBe(64);
+      expect(validateSignatureNoiseMessage(cert, authorityPubKey, staticPubKeyXOnly)).toBe(true);
+    });
+
+    it('should fail validation with wrong authority key', () => {
+      const authorityPrivKey = crypto.randomBytes(32);
+      const wrongPubKey = xOnlyPubKeyFromPriv(crypto.randomBytes(32));
+      const staticPubKeyXOnly = crypto.randomBytes(32);
+
+      const now = Math.floor(Date.now() / 1000);
+      const cert = createSignatureNoiseMessage(authorityPrivKey, staticPubKeyXOnly, now, now + 86400);
+
+      expect(validateSignatureNoiseMessage(cert, wrongPubKey, staticPubKeyXOnly)).toBe(false);
+    });
+
+    it('should serialize and deserialize signature noise message', () => {
+      const msg = {
+        version: 0,
+        validFrom: 1700000000,
+        notValidAfter: 1700086400,
+        signature: crypto.randomBytes(64),
+      };
+      const buf = serializeSignatureNoiseMessage(msg);
+      expect(buf.length).toBe(74);
+      const result = deserializeSignatureNoiseMessage(buf);
+      expect(result.version).toBe(msg.version);
+      expect(result.validFrom).toBe(msg.validFrom);
+      expect(result.notValidAfter).toBe(msg.notValidAfter);
+      expect(result.signature.equals(msg.signature)).toBe(true);
+    });
+  });
+
+  // ── Key Generation ────────────────────────────────────────────────
+
+  describe('Key Generation', () => {
+    it('should generate server keypair with correct sizes', async () => {
+      const kp = await generateServerKeypair();
+      expect(kp.privateKey.length).toBe(32);
+      expect(kp.publicKey.length).toBe(64);
+    });
+
+    it('should produce unique keypairs', async () => {
+      const kp1 = await generateServerKeypair();
+      const kp2 = await generateServerKeypair();
+      expect(kp1.privateKey.equals(kp2.privateKey)).toBe(false);
+    });
+
+    it('should derive x-only pubkey from privkey', () => {
+      const privKey = crypto.randomBytes(32);
+      const xOnly = xOnlyPubKeyFromPriv(privKey);
+      expect(xOnly.length).toBe(32);
+    });
+  });
+
+  // ── EllSwift Loader ───────────────────────────────────────────────
+
+  describe('EllSwift Loader', () => {
+    it('should load EllSwift API', async () => {
+      const es = await loadEllSwift();
+      expect(typeof es.keygen).toBe('function');
+      expect(typeof es.getSharedSecret).toBe('function');
+    });
+
+    it('should cache the loaded module', async () => {
+      const es1 = await loadEllSwift();
+      const es2 = await loadEllSwift();
+      expect(es1).toBe(es2);
+    });
+  });
+
+  // ── Full Noise NX Handshake Self-Test ─────────────────────────────
+
+  describe('Full Handshake', () => {
+    it('should complete NX handshake and exchange encrypted messages', async () => {
+      // 1. Generate server config
+      const serverKeypair = await generateServerKeypair();
+      const authorityPrivKey = crypto.randomBytes(32);
+      const authorityPubKey = xOnlyPubKeyFromPriv(authorityPrivKey);
+      const staticXOnly = xOnlyPubKeyFromPriv(serverKeypair.privateKey);
+
+      const now = Math.floor(Date.now() / 1000);
+      const cert = createSignatureNoiseMessage(
+        authorityPrivKey,
+        staticXOnly,
+        now - 3600,
+        now + 86400,
+      );
+
+      // 2. Create sessions
+      const responder = new Sv2NoiseSession({
+        staticKeypair: serverKeypair,
+        certificateMessage: cert,
+      });
+      const initiator = new Sv2NoiseInitiator();
+
+      // 3. Act 1: Initiator -> Responder (64 bytes)
+      const act1 = await initiator.generateAct1();
+      expect(act1.length).toBe(64);
+
+      // 4. Act 2: Responder -> Initiator (234 bytes)
+      const act2 = await responder.processAct1(act1);
+      expect(act2.length).toBe(234);
+
+      // 5. Initiator processes Act 2
+      const { serverStaticKey, certificate } = initiator.processAct2(act2);
+      expect(serverStaticKey.length).toBe(64);
+      expect(certificate.version).toBe(0);
+
+      // 6. Validate certificate
+      expect(
+        validateSignatureNoiseMessage(certificate, authorityPubKey, staticXOnly),
+      ).toBe(true);
+
+      // 7. Both sides should be ready
+      expect(responder.isHandshakeComplete).toBe(true);
+      expect(initiator.isHandshakeComplete).toBe(true);
+
+      // 8. Exchange encrypted messages: initiator -> responder
+      const msg1 = Buffer.from('hello from initiator');
+      const enc1 = initiator.encrypt(msg1);
+      expect(enc1.length).toBe(msg1.length + SV2_MAC_SIZE);
+      const dec1 = responder.decrypt(enc1);
+      expect(dec1.toString()).toBe('hello from initiator');
+
+      // 9. Exchange encrypted messages: responder -> initiator
+      const msg2 = Buffer.from('hello from responder');
+      const enc2 = responder.encrypt(msg2);
+      const dec2 = initiator.decrypt(enc2);
+      expect(dec2.toString()).toBe('hello from responder');
+
+      // 10. Multiple messages with nonce increment
+      for (let i = 0; i < 5; i++) {
+        const pt = Buffer.from(`bidirectional msg ${i}`);
+        const ct = responder.encrypt(pt);
+        expect(initiator.decrypt(ct).toString()).toBe(`bidirectional msg ${i}`);
+
+        const pt2 = Buffer.from(`reply ${i}`);
+        const ct2 = initiator.encrypt(pt2);
+        expect(responder.decrypt(ct2).toString()).toBe(`reply ${i}`);
+      }
+    });
+
+    it('should fail handshake with wrong Act 1 size', async () => {
+      const serverKeypair = await generateServerKeypair();
+      const authorityPrivKey = crypto.randomBytes(32);
+      const staticXOnly = xOnlyPubKeyFromPriv(serverKeypair.privateKey);
+      const now = Math.floor(Date.now() / 1000);
+      const cert = createSignatureNoiseMessage(authorityPrivKey, staticXOnly, now, now + 86400);
+
+      const responder = new Sv2NoiseSession({
+        staticKeypair: serverKeypair,
+        certificateMessage: cert,
+      });
+
+      await expect(responder.processAct1(Buffer.alloc(32))).rejects.toThrow();
+    });
+
+    it('should not encrypt before handshake is complete', () => {
+      const session = new Sv2NoiseInitiator();
+      expect(() => session.encrypt(Buffer.from('test'))).toThrow('Handshake not complete');
+      expect(() => session.decrypt(Buffer.alloc(32))).toThrow('Handshake not complete');
+    });
+
+    it('should complete NX handshake with AES-256-GCM and exchange encrypted messages', async () => {
+      // 1. Generate server config
+      const serverKeypair = await generateServerKeypair();
+      const authorityPrivKey = crypto.randomBytes(32);
+      const authorityPubKey = xOnlyPubKeyFromPriv(authorityPrivKey);
+      const staticXOnly = xOnlyPubKeyFromPriv(serverKeypair.privateKey);
+
+      const now = Math.floor(Date.now() / 1000);
+      const cert = createSignatureNoiseMessage(
+        authorityPrivKey,
+        staticXOnly,
+        now - 3600,
+        now + 86400,
+      );
+
+      const cipher: Sv2CipherAlgorithm = 'aes-256-gcm';
+
+      // 2. Create sessions with AES-GCM
+      const responder = new Sv2NoiseSession(
+        { staticKeypair: serverKeypair, certificateMessage: cert },
+        cipher,
+      );
+      const initiator = new Sv2NoiseInitiator(cipher);
+
+      // 3. Act 1: Initiator -> Responder (64 bytes)
+      const act1 = await initiator.generateAct1();
+      expect(act1.length).toBe(64);
+
+      // 4. Act 2: Responder -> Initiator (234 bytes)
+      const act2 = await responder.processAct1(act1);
+      expect(act2.length).toBe(234);
+
+      // 5. Initiator processes Act 2
+      const { serverStaticKey, certificate } = initiator.processAct2(act2);
+      expect(serverStaticKey.length).toBe(64);
+      expect(certificate.version).toBe(0);
+
+      // 6. Validate certificate
+      expect(
+        validateSignatureNoiseMessage(certificate, authorityPubKey, staticXOnly),
+      ).toBe(true);
+
+      // 7. Both sides should be ready
+      expect(responder.isHandshakeComplete).toBe(true);
+      expect(initiator.isHandshakeComplete).toBe(true);
+
+      // 8. Exchange encrypted messages: initiator -> responder
+      const msg1 = Buffer.from('hello from AES-GCM initiator');
+      const enc1 = initiator.encrypt(msg1);
+      expect(enc1.length).toBe(msg1.length + SV2_MAC_SIZE);
+      const dec1 = responder.decrypt(enc1);
+      expect(dec1.toString()).toBe('hello from AES-GCM initiator');
+
+      // 9. Exchange encrypted messages: responder -> initiator
+      const msg2 = Buffer.from('hello from AES-GCM responder');
+      const enc2 = responder.encrypt(msg2);
+      const dec2 = initiator.decrypt(enc2);
+      expect(dec2.toString()).toBe('hello from AES-GCM responder');
+
+      // 10. Multiple messages with nonce increment
+      for (let i = 0; i < 5; i++) {
+        const pt = Buffer.from(`AES-GCM bidirectional msg ${i}`);
+        const ct = responder.encrypt(pt);
+        expect(initiator.decrypt(ct).toString()).toBe(`AES-GCM bidirectional msg ${i}`);
+
+        const pt2 = Buffer.from(`AES-GCM reply ${i}`);
+        const ct2 = initiator.encrypt(pt2);
+        expect(responder.decrypt(ct2).toString()).toBe(`AES-GCM reply ${i}`);
+      }
+    });
+
+    it('should not cross-decrypt between ChaCha20 and AES-GCM sessions', async () => {
+      const serverKeypair = await generateServerKeypair();
+      const authorityPrivKey = crypto.randomBytes(32);
+      const staticXOnly = xOnlyPubKeyFromPriv(serverKeypair.privateKey);
+      const now = Math.floor(Date.now() / 1000);
+      const cert = createSignatureNoiseMessage(authorityPrivKey, staticXOnly, now, now + 86400);
+
+      // ChaCha session
+      const chachaResp = new Sv2NoiseSession(
+        { staticKeypair: serverKeypair, certificateMessage: cert },
+      );
+      const chachaInit = new Sv2NoiseInitiator();
+      const chachaAct1 = await chachaInit.generateAct1();
+      const chachaAct2 = await chachaResp.processAct1(chachaAct1);
+      chachaInit.processAct2(chachaAct2);
+
+      // AES-GCM session (different keys, so ciphertexts are incompatible)
+      const serverKeypair2 = await generateServerKeypair();
+      const staticXOnly2 = xOnlyPubKeyFromPriv(serverKeypair2.privateKey);
+      const cert2 = createSignatureNoiseMessage(authorityPrivKey, staticXOnly2, now, now + 86400);
+      const aesResp = new Sv2NoiseSession(
+        { staticKeypair: serverKeypair2, certificateMessage: cert2 },
+        'aes-256-gcm',
+      );
+      const aesInit = new Sv2NoiseInitiator('aes-256-gcm');
+      const aesAct1 = await aesInit.generateAct1();
+      const aesAct2 = await aesResp.processAct1(aesAct1);
+      aesInit.processAct2(aesAct2);
+
+      // Encrypt with ChaCha, try to decrypt with AES-GCM -> should fail
+      const ct = chachaInit.encrypt(Buffer.from('test'));
+      expect(() => aesResp.decrypt(ct)).toThrow();
+    });
+  });
+
+  // ── AES-GCM CipherState ─────────────────────────────────────────────
+
+  describe('CipherState AES-256-GCM', () => {
+    it('should encrypt and decrypt with AES-256-GCM', () => {
+      const key = crypto.randomBytes(32);
+      const enc = new Sv2CipherState('aes-256-gcm');
+      const dec = new Sv2CipherState('aes-256-gcm');
+      enc.initializeKey(key);
+      dec.initializeKey(key);
+
+      const ad = Buffer.alloc(0);
+      const plaintext = Buffer.from('test message for AES-GCM cipher state');
+      const ciphertext = enc.encryptWithAd(ad, plaintext);
+
+      expect(ciphertext.length).toBe(plaintext.length + SV2_MAC_SIZE);
+      const decrypted = dec.decryptWithAd(ad, ciphertext);
+      expect(decrypted.equals(plaintext)).toBe(true);
+    });
+
+    it('should handle multiple sequential encryptions with AES-256-GCM', () => {
+      const key = crypto.randomBytes(32);
+      const enc = new Sv2CipherState('aes-256-gcm');
+      const dec = new Sv2CipherState('aes-256-gcm');
+      enc.initializeKey(key);
+      dec.initializeKey(key);
+
+      const ad = Buffer.alloc(0);
+      for (let i = 0; i < 10; i++) {
+        const pt = Buffer.from(`AES-GCM message ${i}`);
+        const ct = enc.encryptWithAd(ad, pt);
+        const result = dec.decryptWithAd(ad, ct);
+        expect(result.toString()).toBe(`AES-GCM message ${i}`);
+      }
+    });
+
+    it('should encrypt and decrypt with non-empty AD using AES-256-GCM', () => {
+      const key = crypto.randomBytes(32);
+      const enc = new Sv2CipherState('aes-256-gcm');
+      const dec = new Sv2CipherState('aes-256-gcm');
+      enc.initializeKey(key);
+      dec.initializeKey(key);
+
+      const ad = Buffer.from('additional data');
+      const plaintext = Buffer.from('secret payload');
+      const ciphertext = enc.encryptWithAd(ad, plaintext);
+      const decrypted = dec.decryptWithAd(ad, ciphertext);
+      expect(decrypted.equals(plaintext)).toBe(true);
+    });
+  });
+});

src/models/sv2/sv2-noise.ts

@@ -0,0 +1,601 @@
+// ── SV2 Noise NX Handshake & Encrypted Transport ────────────────────
+// Implements Noise_NX_Secp256k1+EllSwift_ChaChaPoly_SHA256 for SV2.
+// Server (responder) side: receives Act 1, sends Act 2, then
+// encrypted transport in both directions.
+
+import * as crypto from 'crypto';
+import * as ecc from 'tiny-secp256k1';
+import {
+  SV2_NOISE_PROTOCOL_NAME,
+  SV2_NOISE_PROTOCOL_NAME_AESGCM,
+  SV2_ELLSWIFT_KEY_SIZE,
+  SV2_MAC_SIZE,
+  SV2_SIGNATURE_NOISE_MSG_SIZE,
+} from './sv2-constants';
+
+// ── Cipher Algorithm Type ───────────────────────────────────────────
+
+export type Sv2CipherAlgorithm = 'chacha20-poly1305' | 'aes-256-gcm';
+
+function getNoiseProtocolName(cipher: Sv2CipherAlgorithm): string {
+  return cipher === 'aes-256-gcm'
+    ? SV2_NOISE_PROTOCOL_NAME_AESGCM
+    : SV2_NOISE_PROTOCOL_NAME;
+}
+
+// ── EllSwift Loader (ESM dynamic import) ────────────────────────────
+
+interface EllSwiftApi {
+  keygen(): { privateKey: Uint8Array; publicKey: Uint8Array };
+  getSharedSecret(privKey: Uint8Array, pubKey: Uint8Array): Uint8Array;
+  getSharedSecretBip324(
+    privateKeyOurs: Uint8Array,
+    publicKeyTheirs: Uint8Array,
+    publicKeyOurs: Uint8Array,
+    initiating: boolean,
+  ): Uint8Array;
+}
+
+let ellSwiftCache: EllSwiftApi | null = null;
+
+export async function loadEllSwift(): Promise<EllSwiftApi> {
+  if (ellSwiftCache) return ellSwiftCache;
+  let mod: any;
+  try {
+    // Works in Jest (ts-jest transforms ESM to CJS) and bundled environments
+    mod = require('@scure/btc-signer/p2p.js');
+  } catch {
+    // Runtime fallback: dynamic import for ESM-only packages in Node CJS mode
+    const importFn = new Function('specifier', 'return import(specifier)');
+    mod = await importFn('@scure/btc-signer/p2p.js');
+  }
+  ellSwiftCache = mod.elligatorSwift as EllSwiftApi;
+  return ellSwiftCache;
+}
+
+// ── Crypto Primitives ───────────────────────────────────────────────
+
+export function hmacHash(key: Buffer, data: Buffer): Buffer {
+  return crypto.createHmac('sha256', key).update(data).digest();
+}
+
+export function sha256(data: Buffer): Buffer {
+  return crypto.createHash('sha256').update(data).digest();
+}
+
+/**
+ * SV2 HKDF with 2 outputs (not RFC 5869).
+ * temp_key = HMAC(chaining_key, input_key_material)
+ * output1 = HMAC(temp_key, 0x01)
+ * output2 = HMAC(temp_key, output1 || 0x02)
+ */
+export function hkdf2(chainingKey: Buffer, ikm: Buffer): [Buffer, Buffer] {
+  const tempKey = hmacHash(chainingKey, ikm);
+  const out1 = hmacHash(tempKey, Buffer.from([0x01]));
+  const out2 = hmacHash(tempKey, Buffer.concat([out1, Buffer.from([0x02])]));
+  return [out1, out2];
+}
+
+// ── CipherState ─────────────────────────────────────────────────────
+
+/**
+ * Nonce encoding per Noise spec:
+ * - ChaCha20-Poly1305 (Section 12.3): 4 zero bytes + LE64(n)
+ * - AES-256-GCM (Section 12.4): 4 zero bytes + BE64(n)
+ *
+ * Set SV2_NONCE_LE=true to force LE for all ciphers (matches SRI Rust behavior).
+ */
+function encodeNonce(n: bigint, algorithm: Sv2CipherAlgorithm): Buffer {
+  const buf = Buffer.alloc(12);
+  if (algorithm === 'aes-256-gcm' && process.env.SV2_NONCE_LE !== 'true') {
+    buf.writeBigUInt64BE(n, 4);
+  } else {
+    buf.writeBigUInt64LE(n, 4);
+  }
+  return buf;
+}
+
+export class Sv2CipherState {
+  private k: Buffer | null = null;
+  private n = 0n;
+  private readonly algorithm: Sv2CipherAlgorithm;
+
+  constructor(algorithm: Sv2CipherAlgorithm = 'chacha20-poly1305') {
+    this.algorithm = algorithm;
+  }
+
+  get hasKey(): boolean {
+    return this.k !== null;
+  }
+
+  initializeKey(key: Buffer): void {
+    if (key.length !== 32) throw new Error('CipherState key must be 32 bytes');
+    this.k = key;
+    this.n = 0n;
+  }
+
+  encryptWithAd(ad: Buffer, plaintext: Buffer): Buffer {
+    if (!this.k) return plaintext;
+    const nonce = encodeNonce(this.n, this.algorithm);
+    const cipher = crypto.createCipheriv(this.algorithm, this.k, nonce, {
+      authTagLength: SV2_MAC_SIZE,
+    } as any) as crypto.CipherGCM;
+    if (this.algorithm === 'aes-256-gcm') {
+      cipher.setAAD(ad, { plaintextLength: plaintext.length } as any);
+    } else {
+      cipher.setAAD(ad, {} as any);
+    }
+    const encrypted = cipher.update(plaintext);
+    cipher.final();
+    const tag = cipher.getAuthTag();
+    this.n++;
+    return Buffer.concat([encrypted, tag]);
+  }
+
+  decryptWithAd(ad: Buffer, ciphertext: Buffer): Buffer {
+    if (!this.k) return ciphertext;
+    if (ciphertext.length < SV2_MAC_SIZE) {
+      throw new Error('Ciphertext too short for MAC');
+    }
+    const nonce = encodeNonce(this.n, this.algorithm);
+    const encData = ciphertext.subarray(0, ciphertext.length - SV2_MAC_SIZE);
+    const tag = ciphertext.subarray(ciphertext.length - SV2_MAC_SIZE);
+    const decipher = crypto.createDecipheriv(this.algorithm, this.k, nonce, {
+      authTagLength: SV2_MAC_SIZE,
+    } as any) as crypto.DecipherGCM;
+    if (this.algorithm === 'aes-256-gcm') {
+      decipher.setAAD(ad, { plaintextLength: encData.length } as any);
+    } else {
+      decipher.setAAD(ad, {} as any);
+    }
+    decipher.setAuthTag(tag);
+    const decrypted = decipher.update(encData);
+    decipher.final();
+    this.n++;
+    return Buffer.from(decrypted);
+  }
+}
+
+// ── Certificate / Signature Noise Message ───────────────────────────
+
+export interface Sv2SignatureNoiseMessage {
+  version: number; // U16
+  validFrom: number; // U32 (unix timestamp)
+  notValidAfter: number; // U32 (unix timestamp)
+  signature: Buffer; // 64-byte Schnorr signature
+}
+
+/**
+ * Serialize a SignatureNoiseMessage to 74 bytes.
+ */
+export function serializeSignatureNoiseMessage(msg: Sv2SignatureNoiseMessage): Buffer {
+  const buf = Buffer.alloc(SV2_SIGNATURE_NOISE_MSG_SIZE);
+  buf.writeUInt16LE(msg.version, 0);
+  buf.writeUInt32LE(msg.validFrom, 2);
+  buf.writeUInt32LE(msg.notValidAfter, 6);
+  msg.signature.copy(buf, 10);
+  return buf;
+}
+
+/**
+ * Deserialize a 74-byte SignatureNoiseMessage.
+ */
+export function deserializeSignatureNoiseMessage(buf: Buffer): Sv2SignatureNoiseMessage {
+  if (buf.length < SV2_SIGNATURE_NOISE_MSG_SIZE) {
+    throw new Error(`SignatureNoiseMessage requires ${SV2_SIGNATURE_NOISE_MSG_SIZE} bytes`);
+  }
+  return {
+    version: buf.readUInt16LE(0),
+    validFrom: buf.readUInt32LE(2),
+    notValidAfter: buf.readUInt32LE(6),
+    signature: Buffer.from(buf.subarray(10, 74)),
+  };
+}
+
+/**
+ * Create a SignatureNoiseMessage that certifies a static key.
+ * Signs: version || validFrom || notValidAfter || staticPubKey (x-only, 32 bytes)
+ * using the authority's private key (BIP-340 Schnorr).
+ */
+export function createSignatureNoiseMessage(
+  authorityPrivKey: Buffer,
+  staticPubKeyXOnly: Buffer,
+  validFrom: number,
+  notValidAfter: number,
+): Sv2SignatureNoiseMessage {
+  const version = 0;
+  const msgBuf = Buffer.alloc(2 + 4 + 4 + 32);
+  msgBuf.writeUInt16LE(version, 0);
+  msgBuf.writeUInt32LE(validFrom, 2);
+  msgBuf.writeUInt32LE(notValidAfter, 6);
+  staticPubKeyXOnly.copy(msgBuf, 10);
+
+  const msgHash = sha256(msgBuf);
+  const sig = ecc.signSchnorr(msgHash, authorityPrivKey);
+  if (!sig) throw new Error('Schnorr signing failed');
+
+  return {
+    version,
+    validFrom,
+    notValidAfter,
+    signature: Buffer.from(sig),
+  };
+}
+
+/**
+ * Validate a SignatureNoiseMessage against an authority public key.
+ */
+export function validateSignatureNoiseMessage(
+  msg: Sv2SignatureNoiseMessage,
+  authorityPubKeyXOnly: Buffer,
+  staticPubKeyXOnly: Buffer,
+): boolean {
+  const msgBuf = Buffer.alloc(2 + 4 + 4 + 32);
+  msgBuf.writeUInt16LE(msg.version, 0);
+  msgBuf.writeUInt32LE(msg.validFrom, 2);
+  msgBuf.writeUInt32LE(msg.notValidAfter, 6);
+  staticPubKeyXOnly.copy(msgBuf, 10);
+
+  const msgHash = sha256(msgBuf);
+  return ecc.verifySchnorr(msgHash, authorityPubKeyXOnly, msg.signature);
+}
+
+// ── Server Keypair Generation ───────────────────────────────────────
+
+export interface Sv2ServerKeypair {
+  privateKey: Buffer; // 32-byte secret scalar
+  publicKey: Buffer; // 64-byte EllSwift-encoded public key
+}
+
+export async function generateServerKeypair(): Promise<Sv2ServerKeypair> {
+  const es = await loadEllSwift();
+  const kp = es.keygen();
+  return {
+    privateKey: Buffer.from(kp.privateKey),
+    publicKey: Buffer.from(kp.publicKey),
+  };
+}
+
+/**
+ * Get the x-only (32-byte) public key from a 32-byte private key.
+ */
+export function xOnlyPubKeyFromPriv(privKey: Buffer): Buffer {
+  const xOnly = ecc.xOnlyPointFromScalar(privKey);
+  if (!xOnly) throw new Error('Failed to derive x-only public key');
+  return Buffer.from(xOnly);
+}
+
+// ── Noise NX Session (Responder / Server side) ──────────────────────
+
+export interface Sv2NoiseConfig {
+  /** Server's static keypair (EllSwift). */
+  staticKeypair: Sv2ServerKeypair;
+  /** Pre-computed certificate message (signed by authority). */
+  certificateMessage: Sv2SignatureNoiseMessage;
+}
+
+export class Sv2NoiseSession {
+  private h: Buffer; // handshake hash
+  private ck: Buffer; // chaining key
+  private tempCipher: Sv2CipherState;
+  private sendCipher: Sv2CipherState;
+  private recvCipher: Sv2CipherState;
+  private handshakeComplete = false;
+  private ellSwift!: EllSwiftApi;
+  private readonly cipherAlgorithm: Sv2CipherAlgorithm;
+
+  private serverEphemeralPriv!: Buffer;
+  private serverEphemeralPub!: Buffer;
+
+  constructor(
+    private readonly config: Sv2NoiseConfig,
+    cipherAlgorithm: Sv2CipherAlgorithm = 'chacha20-poly1305',
+    prologue: Buffer = Buffer.alloc(0),
+  ) {
+    this.cipherAlgorithm = cipherAlgorithm;
+
+    const protocolNameStr = getNoiseProtocolName(cipherAlgorithm);
+
+    this.tempCipher = new Sv2CipherState(cipherAlgorithm);
+    this.sendCipher = new Sv2CipherState(cipherAlgorithm);
+    this.recvCipher = new Sv2CipherState(cipherAlgorithm);
+
+    // Initialize h = HASH(protocol_name) if len > 32, else pad
+    const protocolName = Buffer.from(protocolNameStr, 'ascii');
+    if (protocolName.length <= 32) {
+      this.h = Buffer.alloc(32);
+      protocolName.copy(this.h);
+    } else {
+      this.h = sha256(protocolName);
+    }
+    // ck = h
+    this.ck = Buffer.from(this.h);
+    // MixHash(prologue) per Noise spec: h = HASH(h || prologue)
+    this.h = sha256(Buffer.concat([this.h, prologue]));
+  }
+
+  // ── Noise Symmetric State Helpers ─────────────────────────────────
+
+  private mixHash(data: Buffer): void {
+    this.h = sha256(Buffer.concat([this.h, data]));
+  }
+
+  private mixKey(ikm: Buffer): void {
+    const [newCk, tempK] = hkdf2(this.ck, ikm);
+    this.ck = newCk;
+    this.tempCipher = new Sv2CipherState(this.cipherAlgorithm);
+    this.tempCipher.initializeKey(tempK);
+  }
+
+  private encryptAndHash(plaintext: Buffer): Buffer {
+    const ciphertext = this.tempCipher.encryptWithAd(this.h, plaintext);
+    this.mixHash(ciphertext);
+    return ciphertext;
+  }
+
+  private decryptAndHash(ciphertext: Buffer): Buffer {
+    const plaintext = this.tempCipher.decryptWithAd(this.h, ciphertext);
+    this.mixHash(ciphertext);
+    return plaintext;
+  }
+
+  // ── ECDH via EllSwift ─────────────────────────────────────────────
+
+  /**
+   * Compute BIP-324 EllSwift ECDH.
+   * @param localPriv - Our private key (32 bytes)
+   * @param localPub - Our EllSwift public key (64 bytes)
+   * @param remotePub - Their EllSwift public key (64 bytes)
+   * @param weAreInitiator - Party bit: true for initiator, false for responder
+   */
+  private ecdh(localPriv: Buffer, localPub: Buffer, remotePub: Buffer, weAreInitiator: boolean): Buffer {
+    const secret = this.ellSwift.getSharedSecretBip324(
+      new Uint8Array(localPriv),
+      new Uint8Array(remotePub),
+      new Uint8Array(localPub),
+      weAreInitiator,
+    );
+    return Buffer.from(secret);
+  }
+
+  // ── Handshake: Process Act 1, Generate Act 2 ─────────────────────
+
+  /**
+   * Process the initiator's Act 1 ephemeral key and produce Act 2.
+   * EllSwift mode: 64-byte Act 1 -> 234-byte Act 2
+   */
+  async processAct1(act1: Buffer): Promise<Buffer> {
+    if (act1.length !== SV2_ELLSWIFT_KEY_SIZE) {
+      throw new Error(`Act 1 must be ${SV2_ELLSWIFT_KEY_SIZE} bytes, got ${act1.length}`);
+    }
+
+    const debug = process.env.SV2_NOISE_DEBUG === 'true';
+
+    if (debug) {
+      const protocolNameStr = getNoiseProtocolName(this.cipherAlgorithm);
+      console.log(`[NOISE] Protocol name: "${protocolNameStr}" (${protocolNameStr.length} bytes)`);
+      console.log(`[NOISE] Cipher: ${this.cipherAlgorithm}`);
+      console.log(`[NOISE] Init ck=${this.ck.toString('hex')}`);
+      console.log(`[NOISE] Init h=${this.h.toString('hex')}`);
+    }
+
+    this.ellSwift = await loadEllSwift();
+
+    const remoteEphemeral = act1;
+    this.mixHash(remoteEphemeral);
+    if (debug) console.log(`[NOISE] After MixHash(re): h=${this.h.toString('hex')}`);
+
+    this.decryptAndHash(Buffer.alloc(0));
+    if (debug) console.log(`[NOISE] After DecryptAndHash(empty): h=${this.h.toString('hex')}`);
+
+    const serverEph = this.ellSwift.keygen();
+    this.serverEphemeralPriv = Buffer.from(serverEph.privateKey);
+    this.serverEphemeralPub = Buffer.from(serverEph.publicKey);
+
+    if (debug) console.log(`[NOISE] Server eph pub: ${this.serverEphemeralPub.toString('hex')}`);
+
+    this.mixHash(this.serverEphemeralPub);
+    if (debug) console.log(`[NOISE] After MixHash(se): h=${this.h.toString('hex')}`);
+
+    const eeDH = this.ecdh(
+      this.serverEphemeralPriv,
+      this.serverEphemeralPub,
+      remoteEphemeral,
+      false,
+    );
+    if (debug) console.log(`[NOISE] ee DH shared secret: ${eeDH.toString('hex')}`);
+
+    this.mixKey(eeDH);
+    if (debug) console.log(`[NOISE] After MixKey(ee): ck=${this.ck.toString('hex')}`);
+
+    const staticPubKey = this.config.staticKeypair.publicKey;
+    if (debug) {
+      console.log(`[NOISE] h (AD for encrypt static): ${this.h.toString('hex')}`);
+      console.log(`[NOISE] Static pub (plaintext): ${staticPubKey.toString('hex')}`);
+    }
+
+    const encryptedStatic = this.encryptAndHash(staticPubKey);
+    if (debug) console.log(`[NOISE] Encrypted static (${encryptedStatic.length} bytes): ${encryptedStatic.toString('hex')}`);
+
+    const esDH = this.ecdh(
+      this.config.staticKeypair.privateKey,
+      this.config.staticKeypair.publicKey,
+      remoteEphemeral,
+      false,
+    );
+    if (debug) console.log(`[NOISE] es DH shared secret: ${esDH.toString('hex')}`);
+
+    this.mixKey(esDH);
+    if (debug) console.log(`[NOISE] After MixKey(es): ck=${this.ck.toString('hex')}`);
+
+    const certPayload = serializeSignatureNoiseMessage(this.config.certificateMessage);
+    if (debug) console.log(`[NOISE] h (AD for encrypt cert): ${this.h.toString('hex')}`);
+    if (debug) console.log(`[NOISE] Cert payload (${certPayload.length} bytes): ${certPayload.toString('hex')}`);
+
+    const encryptedCert = this.encryptAndHash(certPayload);
+    if (debug) console.log(`[NOISE] Encrypted cert (${encryptedCert.length} bytes)`);
+
+    const [k1, k2] = hkdf2(this.ck, Buffer.alloc(0));
+    this.recvCipher.initializeKey(k1);
+    this.sendCipher.initializeKey(k2);
+    this.handshakeComplete = true;
+
+    const act2 = Buffer.concat([this.serverEphemeralPub, encryptedStatic, encryptedCert]);
+    if (debug) console.log(`[NOISE] Act 2 total: ${act2.length} bytes`);
+
+    return act2;
+  }
+
+  // ── Post-Handshake Transport ──────────────────────────────────────
+
+  encrypt(plaintext: Buffer): Buffer {
+    if (!this.handshakeComplete) throw new Error('Handshake not complete');
+    return this.sendCipher.encryptWithAd(Buffer.alloc(0), plaintext);
+  }
+
+  decrypt(ciphertext: Buffer): Buffer {
+    if (!this.handshakeComplete) throw new Error('Handshake not complete');
+    return this.recvCipher.decryptWithAd(Buffer.alloc(0), ciphertext);
+  }
+
+  get isHandshakeComplete(): boolean {
+    return this.handshakeComplete;
+  }
+}
+
+// ── Initiator Session (for testing) ─────────────────────────────────
+
+export class Sv2NoiseInitiator {
+  private h: Buffer;
+  private ck: Buffer;
+  private tempCipher: Sv2CipherState;
+  private sendCipher: Sv2CipherState;
+  private recvCipher: Sv2CipherState;
+  private handshakeComplete = false;
+  private ellSwift!: EllSwiftApi;
+  private readonly cipherAlgorithm: Sv2CipherAlgorithm;
+
+  private ephemeralPriv!: Buffer;
+  private ephemeralPub!: Buffer;
+
+  constructor(
+    cipherAlgorithm: Sv2CipherAlgorithm = 'chacha20-poly1305',
+    prologue: Buffer = Buffer.alloc(0),
+  ) {
+    this.cipherAlgorithm = cipherAlgorithm;
+
+    const protocolNameStr = getNoiseProtocolName(cipherAlgorithm);
+
+    this.tempCipher = new Sv2CipherState(cipherAlgorithm);
+    this.sendCipher = new Sv2CipherState(cipherAlgorithm);
+    this.recvCipher = new Sv2CipherState(cipherAlgorithm);
+
+    const protocolName = Buffer.from(protocolNameStr, 'ascii');
+    if (protocolName.length <= 32) {
+      this.h = Buffer.alloc(32);
+      protocolName.copy(this.h);
+    } else {
+      this.h = sha256(protocolName);
+    }
+    this.ck = Buffer.from(this.h);
+    // MixHash(prologue) per Noise spec: h = HASH(h || prologue)
+    this.h = sha256(Buffer.concat([this.h, prologue]));
+  }
+
+  private mixHash(data: Buffer): void {
+    this.h = sha256(Buffer.concat([this.h, data]));
+  }
+
+  private mixKey(ikm: Buffer): void {
+    const [newCk, tempK] = hkdf2(this.ck, ikm);
+    this.ck = newCk;
+    this.tempCipher = new Sv2CipherState(this.cipherAlgorithm);
+    this.tempCipher.initializeKey(tempK);
+  }
+
+  private decryptAndHash(ciphertext: Buffer): Buffer {
+    const plaintext = this.tempCipher.decryptWithAd(this.h, ciphertext);
+    this.mixHash(ciphertext);
+    return plaintext;
+  }
+
+  private ecdh(localPriv: Buffer, localPub: Buffer, remotePub: Buffer, weAreInitiator: boolean): Buffer {
+    const secret = this.ellSwift.getSharedSecretBip324(
+      new Uint8Array(localPriv),
+      new Uint8Array(remotePub),
+      new Uint8Array(localPub),
+      weAreInitiator,
+    );
+    return Buffer.from(secret);
+  }
+
+  /** Generate Act 1: 64-byte EllSwift ephemeral key. */
+  async generateAct1(): Promise<Buffer> {
+    this.ellSwift = await loadEllSwift();
+    const kp = this.ellSwift.keygen();
+    this.ephemeralPriv = Buffer.from(kp.privateKey);
+    this.ephemeralPub = Buffer.from(kp.publicKey);
+
+    this.mixHash(this.ephemeralPub);
+    this.mixHash(Buffer.alloc(0));
+    return this.ephemeralPub;
+  }
+
+  /** Process Act 2 from responder, returns the decrypted server static key and cert. */
+  processAct2(act2: Buffer): {
+    serverStaticKey: Buffer;
+    certificate: Sv2SignatureNoiseMessage;
+  } {
+    if (act2.length !== 234) {
+      throw new Error(`Act 2 must be 234 bytes, got ${act2.length}`);
+    }
+
+    const serverEphemeral = act2.subarray(0, 64);
+    const encryptedStatic = act2.subarray(64, 144);
+    const encryptedCert = act2.subarray(144, 234);
+
+    this.mixHash(Buffer.from(serverEphemeral));
+
+    const eeDH = this.ecdh(
+      this.ephemeralPriv,
+      this.ephemeralPub,
+      Buffer.from(serverEphemeral),
+      true,
+    );
+    this.mixKey(eeDH);
+
+    const serverStaticKey = this.decryptAndHash(Buffer.from(encryptedStatic));
+
+    const esDH = this.ecdh(
+      this.ephemeralPriv,
+      this.ephemeralPub,
+      serverStaticKey,
+      true,
+    );
+    this.mixKey(esDH);
+
+    const certPayload = this.decryptAndHash(Buffer.from(encryptedCert));
+    const certificate = deserializeSignatureNoiseMessage(certPayload);
+
+    const [k1, k2] = hkdf2(this.ck, Buffer.alloc(0));
+    this.sendCipher.initializeKey(k1);
+    this.recvCipher.initializeKey(k2);
+    this.handshakeComplete = true;
+
+    return { serverStaticKey, certificate };
+  }
+
+  encrypt(plaintext: Buffer): Buffer {
+    if (!this.handshakeComplete) throw new Error('Handshake not complete');
+    return this.sendCipher.encryptWithAd(Buffer.alloc(0), plaintext);
+  }
+
+  decrypt(ciphertext: Buffer): Buffer {
+    if (!this.handshakeComplete) throw new Error('Handshake not complete');
+    return this.recvCipher.decryptWithAd(Buffer.alloc(0), ciphertext);
+  }
+
+  get isHandshakeComplete(): boolean {
+    return this.handshakeComplete;
+  }
+}

src/models/sv2/sv2-siphash.spec.ts

@@ -0,0 +1,107 @@
+import { sipHash24, shortTxId, sipHashKeyFromNonce } from './sv2-siphash';
+
+describe('SipHash-2-4', () => {
+  // Official SipHash-2-4 test vectors from the reference paper
+  // Key: 00 01 02 ... 0f
+  // Input: empty, 00, 00 01, 00 01 02, ...
+  // Expected outputs (first few from Appendix A of the paper)
+  const testKey = Buffer.from([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]);
+
+  // Reference vectors from vectors.h: uint8_t vectors_sip64[64][8]
+  // These are the raw output bytes, so we compare directly with our output buffer.
+  const expectedOutputs = [
+    '310e0edd47db6f72', // empty input
+    'fd67dc93c539f874', // [0x00]
+    '5a4fa9d909806c0d', // [0x00, 0x01]
+    '2d7efbd796666785', // [0x00, 0x01, 0x02]
+    'b7877127e09427cf', // [0x00, 0x01, 0x02, 0x03]
+    '8da699cd64557618', // [0x00, ..., 0x04]
+    'cee3fe586e46c9cb', // [0x00, ..., 0x05]
+    '37d1018bf50002ab', // [0x00, ..., 0x06]
+    '6224939a79f5f593', // [0x00, ..., 0x07]
+    'b0e4a90bdf82009e', // [0x00, ..., 0x08]
+    'f3b9dd94c5bb5d7a', // [0x00, ..., 0x09]
+    'a7ad6b22462fb3f4', // [0x00, ..., 0x0a]
+    'fbe50e86bc8f1e75', // [0x00, ..., 0x0b]
+    '903d84c02756ea14', // [0x00, ..., 0x0c]
+    'eef27a8e90ca23f7', // [0x00, ..., 0x0d]
+    'e545be4961ca29a1', // [0x00, ..., 0x0e]
+  ];
+
+  expectedOutputs.forEach((expected, i) => {
+    it(`matches test vector for ${i}-byte input`, () => {
+      const input = Buffer.from(Array.from({ length: i }, (_, j) => j));
+      const result = sipHash24(testKey, input);
+      // Compare raw output bytes directly
+      expect(result.toString('hex')).toBe(expected);
+    });
+  });
+
+  it('throws for invalid key length', () => {
+    expect(() => sipHash24(Buffer.alloc(8), Buffer.alloc(0))).toThrow('SipHash key must be 16 bytes');
+    expect(() => sipHash24(Buffer.alloc(32), Buffer.alloc(0))).toThrow('SipHash key must be 16 bytes');
+  });
+
+  it('produces 8-byte output', () => {
+    const result = sipHash24(testKey, Buffer.from('hello'));
+    expect(result.length).toBe(8);
+  });
+
+  it('produces consistent results', () => {
+    const data = Buffer.from('test data');
+    const r1 = sipHash24(testKey, data);
+    const r2 = sipHash24(testKey, data);
+    expect(r1).toEqual(r2);
+  });
+
+  it('different keys produce different results', () => {
+    const key2 = Buffer.alloc(16, 0xff);
+    const data = Buffer.from('hello');
+    const r1 = sipHash24(testKey, data);
+    const r2 = sipHash24(key2, data);
+    expect(r1).not.toEqual(r2);
+  });
+
+  describe('shortTxId', () => {
+    it('produces 6-byte output', () => {
+      const txHash = Buffer.alloc(32, 0xab);
+      const result = shortTxId(testKey, txHash);
+      expect(result.length).toBe(6);
+    });
+
+    it('is the first 6 bytes of sipHash24', () => {
+      const txHash = Buffer.alloc(32, 0xcd);
+      const full = sipHash24(testKey, txHash);
+      const short = shortTxId(testKey, txHash);
+      expect(short).toEqual(full.subarray(0, 6));
+    });
+
+    it('different tx hashes produce different short IDs', () => {
+      const tx1 = Buffer.alloc(32, 0x01);
+      const tx2 = Buffer.alloc(32, 0x02);
+      const s1 = shortTxId(testKey, tx1);
+      const s2 = shortTxId(testKey, tx2);
+      expect(s1).not.toEqual(s2);
+    });
+  });
+
+  describe('sipHashKeyFromNonce', () => {
+    it('produces 16-byte key', () => {
+      const key = sipHashKeyFromNonce(42n);
+      expect(key.length).toBe(16);
+    });
+
+    it('nonce is stored in first 8 bytes LE', () => {
+      const key = sipHashKeyFromNonce(0x0102030405060708n);
+      expect(key.readBigUInt64LE(0)).toBe(0x0102030405060708n);
+      // Second 8 bytes should be zero
+      expect(key.readBigUInt64LE(8)).toBe(0n);
+    });
+
+    it('produces valid SipHash key', () => {
+      const key = sipHashKeyFromNonce(12345n);
+      const result = sipHash24(key, Buffer.from('test'));
+      expect(result.length).toBe(8);
+    });
+  });
+});

src/models/sv2/sv2-siphash.ts

@@ -0,0 +1,154 @@
+// ── SipHash-2-4 ────────────────────────────────────────────────────
+// Pure TypeScript implementation of SipHash-2-4 for SV2 JDP short
+// transaction IDs. Produces 8-byte (64-bit) hashes, truncated to
+// 6 bytes per the SV2 spec for SHORT_TX_ID.
+//
+// Reference: https://131002.net/siphash/siphash.pdf
+
+function add64(a: [number, number], b: [number, number]): [number, number] {
+  const lo = (a[1] + b[1]) >>> 0;
+  const hi = ((a[0] + b[0]) >>> 0) + (lo < a[1] ? 1 : 0);
+  return [(hi >>> 0), lo];
+}
+
+function rotl64(v: [number, number], n: number): [number, number] {
+  if (n === 0) return v;
+  if (n === 32) return [v[1], v[0]];
+  if (n < 32) {
+    return [
+      ((v[0] << n) | (v[1] >>> (32 - n))) >>> 0,
+      ((v[1] << n) | (v[0] >>> (32 - n))) >>> 0,
+    ];
+  }
+  const s = n - 32;
+  return [
+    ((v[1] << s) | (v[0] >>> (32 - s))) >>> 0,
+    ((v[0] << s) | (v[1] >>> (32 - s))) >>> 0,
+  ];
+}
+
+function xor64(a: [number, number], b: [number, number]): [number, number] {
+  return [(a[0] ^ b[0]) >>> 0, (a[1] ^ b[1]) >>> 0];
+}
+
+function sipRound(
+  v0: [number, number],
+  v1: [number, number],
+  v2: [number, number],
+  v3: [number, number],
+): [[number, number], [number, number], [number, number], [number, number]] {
+  v0 = add64(v0, v1);
+  v1 = rotl64(v1, 13);
+  v1 = xor64(v1, v0);
+  v0 = rotl64(v0, 32);
+
+  v2 = add64(v2, v3);
+  v3 = rotl64(v3, 16);
+  v3 = xor64(v3, v2);
+
+  v2 = add64(v2, v1);
+  v1 = rotl64(v1, 17);
+  v1 = xor64(v1, v2);
+  v2 = rotl64(v2, 32);
+
+  v0 = add64(v0, v3);
+  v3 = rotl64(v3, 21);
+  v3 = xor64(v3, v0);
+
+  return [v0, v1, v2, v3];
+}
+
+function readU64LE(buf: Buffer, offset: number): [number, number] {
+  const lo = buf.readUInt32LE(offset);
+  const hi = buf.readUInt32LE(offset + 4);
+  return [hi, lo];
+}
+
+/**
+ * SipHash-2-4 producing an 8-byte hash.
+ * @param key 16-byte key
+ * @param data input data
+ * @returns 8-byte Buffer (little-endian hash)
+ */
+export function sipHash24(key: Buffer, data: Buffer): Buffer {
+  if (key.length !== 16) throw new Error('SipHash key must be 16 bytes');
+
+  const k0 = readU64LE(key, 0);
+  const k1 = readU64LE(key, 8);
+
+  let v0: [number, number] = xor64(k0, [0x736f6d65, 0x70736575]); // "somepseu"
+  let v1: [number, number] = xor64(k1, [0x646f7261, 0x6e646f6d]); // "dorandom"
+  let v2: [number, number] = xor64(k0, [0x6c796765, 0x6e657261]); // "lygenera"
+  let v3: [number, number] = xor64(k1, [0x74656462, 0x79746573]); // "tedbytes"
+
+  const len = data.length;
+  const blocks = Math.floor(len / 8);
+
+  // Process 8-byte blocks
+  for (let i = 0; i < blocks; i++) {
+    const m = readU64LE(data, i * 8);
+    v3 = xor64(v3, m);
+    // 2 rounds (SipHash-2-4)
+    [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+    [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+    v0 = xor64(v0, m);
+  }
+
+  // Last block: remaining bytes + length in the high byte
+  const remaining = len - blocks * 8;
+  let last: [number, number] = [0, 0];
+
+  // High byte of hi word = (len & 0xff) << 24
+  last[0] = ((len & 0xff) << 24) >>> 0;
+
+  // Read remaining bytes
+  const offset = blocks * 8;
+  if (remaining >= 7) last[0] |= (data[offset + 6] << 16) >>> 0;
+  if (remaining >= 6) last[0] |= (data[offset + 5] << 8) >>> 0;
+  if (remaining >= 5) last[0] |= data[offset + 4];
+  if (remaining >= 4) last[1] = (last[1] | ((data[offset + 3] << 24) >>> 0)) >>> 0;
+  if (remaining >= 3) last[1] = (last[1] | ((data[offset + 2] << 16) >>> 0)) >>> 0;
+  if (remaining >= 2) last[1] = (last[1] | ((data[offset + 1] << 8) >>> 0)) >>> 0;
+  if (remaining >= 1) last[1] = (last[1] | data[offset]) >>> 0;
+
+  v3 = xor64(v3, last);
+  [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+  [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+  v0 = xor64(v0, last);
+
+  // Finalization
+  v2 = xor64(v2, [0, 0xff]);
+  [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+  [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+  [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+  [v0, v1, v2, v3] = sipRound(v0, v1, v2, v3);
+
+  const result = xor64(xor64(v0, v1), xor64(v2, v3));
+
+  const out = Buffer.alloc(8);
+  out.writeUInt32LE(result[1], 0);
+  out.writeUInt32LE(result[0], 4);
+  return out;
+}
+
+/**
+ * Compute a 6-byte SHORT_TX_ID per SV2 spec.
+ * SipHash-2-4(key, txid) truncated to first 6 bytes.
+ * @param key 16-byte key (derived from nonce)
+ * @param txHash 32-byte transaction hash
+ * @returns 6-byte Buffer
+ */
+export function shortTxId(key: Buffer, txHash: Buffer): Buffer {
+  const hash = sipHash24(key, txHash);
+  return hash.subarray(0, 6);
+}
+
+/**
+ * Build a 16-byte SipHash key from a U64 nonce.
+ * First 8 bytes = nonce LE, second 8 bytes = zeros.
+ */
+export function sipHashKeyFromNonce(nonce: bigint): Buffer {
+  const key = Buffer.alloc(16);
+  key.writeBigUInt64LE(nonce, 0);
+  return key;
+}

src/models/sv2/sv2-tdp-messages.spec.ts

@@ -0,0 +1,226 @@
+import { BufferReader } from './sv2-binary-codec';
+import {
+  Sv2TdpCoinbaseOutputConstraints,
+  serializeTdpCoinbaseOutputConstraints,
+  deserializeTdpCoinbaseOutputConstraints,
+  Sv2TdpNewTemplate,
+  serializeTdpNewTemplate,
+  deserializeTdpNewTemplate,
+  Sv2TdpSetNewPrevHash,
+  serializeTdpSetNewPrevHash,
+  deserializeTdpSetNewPrevHash,
+  Sv2TdpRequestTransactionData,
+  serializeTdpRequestTransactionData,
+  deserializeTdpRequestTransactionData,
+  Sv2TdpRequestTransactionDataSuccess,
+  serializeTdpRequestTransactionDataSuccess,
+  deserializeTdpRequestTransactionDataSuccess,
+  Sv2TdpRequestTransactionDataError,
+  serializeTdpRequestTransactionDataError,
+  deserializeTdpRequestTransactionDataError,
+  Sv2TdpSubmitSolution,
+  serializeTdpSubmitSolution,
+  deserializeTdpSubmitSolution,
+} from './sv2-tdp-messages';
+
+function roundTrip<T>(
+  msg: T,
+  serialize: (m: T) => Buffer,
+  deserialize: (r: BufferReader) => T,
+): T {
+  const buf = serialize(msg);
+  return deserialize(new BufferReader(buf));
+}
+
+describe('SV2 TDP Messages', () => {
+  it('CoinbaseOutputConstraints round-trips', () => {
+    const msg: Sv2TdpCoinbaseOutputConstraints = {
+      coinbaseOutputMaxAdditionalSize: 128,
+      coinbaseOutputMaxAdditionalSigops: 400,
+    };
+    const result = roundTrip(msg, serializeTdpCoinbaseOutputConstraints, deserializeTdpCoinbaseOutputConstraints);
+    expect(result).toEqual(msg);
+  });
+
+  it('NewTemplate round-trips with merkle path', () => {
+    const hash1 = Buffer.alloc(32, 0xaa);
+    const hash2 = Buffer.alloc(32, 0xbb);
+    const msg: Sv2TdpNewTemplate = {
+      templateId: 42n,
+      futureTemplate: false,
+      version: 0x20000000,
+      coinbaseTxVersion: 2,
+      coinbasePrefix: Buffer.from('deadbeef', 'hex'),
+      coinbaseTxInputSequence: 0xffffffff,
+      coinbaseTxValueRemaining: 625000000n,
+      coinbaseTxOutputsCount: 1,
+      coinbaseTxOutputs: Buffer.from('cafebabe', 'hex'),
+      coinbaseTxLocktime: 0,
+      merklePath: [hash1, hash2],
+    };
+    const result = roundTrip(msg, serializeTdpNewTemplate, deserializeTdpNewTemplate);
+    expect(result.templateId).toBe(msg.templateId);
+    expect(result.futureTemplate).toBe(msg.futureTemplate);
+    expect(result.version).toBe(msg.version);
+    expect(result.coinbasePrefix).toEqual(msg.coinbasePrefix);
+    expect(result.coinbaseTxVersion).toBe(msg.coinbaseTxVersion);
+    expect(result.coinbaseTxInputSequence).toBe(msg.coinbaseTxInputSequence);
+    expect(result.coinbaseTxValueRemaining).toBe(msg.coinbaseTxValueRemaining);
+    expect(result.coinbaseTxOutputsCount).toBe(msg.coinbaseTxOutputsCount);
+    expect(result.coinbaseTxOutputs).toEqual(msg.coinbaseTxOutputs);
+    expect(result.coinbaseTxLocktime).toBe(msg.coinbaseTxLocktime);
+    expect(result.merklePath).toHaveLength(2);
+    expect(result.merklePath[0]).toEqual(hash1);
+    expect(result.merklePath[1]).toEqual(hash2);
+  });
+
+  it('NewTemplate round-trips with empty merkle path', () => {
+    const msg: Sv2TdpNewTemplate = {
+      templateId: 1n,
+      futureTemplate: true,
+      version: 0x20000000,
+      coinbaseTxVersion: 2,
+      coinbasePrefix: Buffer.alloc(0),
+      coinbaseTxInputSequence: 0xffffffff,
+      coinbaseTxValueRemaining: 0n,
+      coinbaseTxOutputsCount: 0,
+      coinbaseTxOutputs: Buffer.alloc(0),
+      coinbaseTxLocktime: 0,
+      merklePath: [],
+    };
+    const result = roundTrip(msg, serializeTdpNewTemplate, deserializeTdpNewTemplate);
+    expect(result.merklePath).toHaveLength(0);
+    expect(result.futureTemplate).toBe(true);
+  });
+
+  it('NewTemplate round-trips with large coinbase data', () => {
+    const largeCoinbase = Buffer.alloc(100, 0xcc); // B0_255 max 255 bytes
+    const largeOutputs = Buffer.alloc(2000, 0xdd);
+    const msg: Sv2TdpNewTemplate = {
+      templateId: 999n,
+      futureTemplate: false,
+      version: 0x20400000,
+      coinbaseTxVersion: 2,
+      coinbasePrefix: largeCoinbase,
+      coinbaseTxInputSequence: 0xfffffffe,
+      coinbaseTxValueRemaining: 312500000n,
+      coinbaseTxOutputsCount: 3,
+      coinbaseTxOutputs: largeOutputs,
+      coinbaseTxLocktime: 500000,
+      merklePath: Array.from({ length: 12 }, (_, i) => Buffer.alloc(32, i)),
+    };
+    const result = roundTrip(msg, serializeTdpNewTemplate, deserializeTdpNewTemplate);
+    expect(result.coinbasePrefix).toEqual(largeCoinbase); // B0_255, 100 bytes
+    expect(result.coinbaseTxOutputs).toEqual(largeOutputs);
+    expect(result.merklePath).toHaveLength(12);
+  });
+
+  it('SetNewPrevHash round-trips', () => {
+    const prevHash = Buffer.alloc(32, 0xab);
+    const target = Buffer.alloc(32, 0x00);
+    target[0] = 0xff;
+    const msg: Sv2TdpSetNewPrevHash = {
+      templateId: 42n,
+      prevHash,
+      headerTimestamp: 1700000000,
+      nBits: 0x1d00ffff,
+      target,
+    };
+    const result = roundTrip(msg, serializeTdpSetNewPrevHash, deserializeTdpSetNewPrevHash);
+    expect(result).toEqual(msg);
+  });
+
+  it('RequestTransactionData round-trips', () => {
+    const msg: Sv2TdpRequestTransactionData = {
+      templateId: 100n,
+    };
+    const result = roundTrip(msg, serializeTdpRequestTransactionData, deserializeTdpRequestTransactionData);
+    expect(result).toEqual(msg);
+  });
+
+  it('RequestTransactionData.Success round-trips with transactions', () => {
+    const tx1 = Buffer.from('0100000001', 'hex');
+    const tx2 = Buffer.from('0200000002abcd', 'hex');
+    const msg: Sv2TdpRequestTransactionDataSuccess = {
+      templateId: 100n,
+      excessData: Buffer.from('extra', 'utf8'),
+      transactionList: [tx1, tx2],
+    };
+    const result = roundTrip(
+      msg,
+      serializeTdpRequestTransactionDataSuccess,
+      deserializeTdpRequestTransactionDataSuccess,
+    );
+    expect(result.templateId).toBe(msg.templateId);
+    expect(result.excessData).toEqual(msg.excessData);
+    expect(result.transactionList).toHaveLength(2);
+    expect(result.transactionList[0]).toEqual(tx1);
+    expect(result.transactionList[1]).toEqual(tx2);
+  });
+
+  it('RequestTransactionData.Success round-trips with empty transaction list', () => {
+    const msg: Sv2TdpRequestTransactionDataSuccess = {
+      templateId: 1n,
+      excessData: Buffer.alloc(0),
+      transactionList: [],
+    };
+    const result = roundTrip(
+      msg,
+      serializeTdpRequestTransactionDataSuccess,
+      deserializeTdpRequestTransactionDataSuccess,
+    );
+    expect(result.transactionList).toHaveLength(0);
+  });
+
+  it('RequestTransactionData.Error round-trips', () => {
+    const msg: Sv2TdpRequestTransactionDataError = {
+      templateId: 42n,
+      errorCode: 'template-not-found',
+    };
+    const result = roundTrip(
+      msg,
+      serializeTdpRequestTransactionDataError,
+      deserializeTdpRequestTransactionDataError,
+    );
+    expect(result).toEqual(msg);
+  });
+
+  it('SubmitSolution round-trips', () => {
+    const coinbaseTx = Buffer.alloc(250, 0xef);
+    const msg: Sv2TdpSubmitSolution = {
+      templateId: 42n,
+      version: 0x20000000,
+      headerTimestamp: 1700000000,
+      headerNonce: 0xdeadbeef,
+      coinbaseTx,
+    };
+    const result = roundTrip(msg, serializeTdpSubmitSolution, deserializeTdpSubmitSolution);
+    expect(result.templateId).toBe(msg.templateId);
+    expect(result.version).toBe(msg.version);
+    expect(result.headerTimestamp).toBe(msg.headerTimestamp);
+    expect(result.headerNonce).toBe(msg.headerNonce);
+    expect(result.coinbaseTx).toEqual(coinbaseTx);
+  });
+
+  it('serialized NewTemplate has correct byte layout', () => {
+    const msg: Sv2TdpNewTemplate = {
+      templateId: 1n,
+      futureTemplate: false,
+      version: 0x20000000,
+      coinbaseTxVersion: 2,
+      coinbasePrefix: Buffer.from([0xab]),
+      coinbaseTxInputSequence: 0xffffffff,
+      coinbaseTxValueRemaining: 100n,
+      coinbaseTxOutputsCount: 0,
+      coinbaseTxOutputs: Buffer.alloc(0),
+      coinbaseTxLocktime: 0,
+      merklePath: [],
+    };
+    const buf = serializeTdpNewTemplate(msg);
+    // U64(8) + BOOL(1) + U32(4) + U32(4) + B0_255(1+1) + U32(4) + U64(8) + U32(4) + B0_64K(2+0) + U32(4) + SEQ0_255(1+0)
+    // = 8 + 1 + 4 + 4 + 2 + 4 + 8 + 4 + 2 + 4 + 1 = 42
+    expect(buf.length).toBe(42);
+    expect(buf.readBigUInt64LE(0)).toBe(1n);
+    expect(buf[8]).toBe(0); // futureTemplate = false
+  });
+});

src/models/sv2/sv2-tdp-messages.ts

@@ -0,0 +1,196 @@
+// ── SV2 Template Distribution Protocol (TDP) Messages ──────────────
+// Interfaces + serialize/deserialize for all TDP message types.
+
+import { BufferReader, BufferWriter } from './sv2-binary-codec';
+
+// ── CoinbaseOutputConstraints (0x70) ────────────────────────────────
+
+export interface Sv2TdpCoinbaseOutputConstraints {
+  coinbaseOutputMaxAdditionalSize: number;   // U32
+  coinbaseOutputMaxAdditionalSigops: number; // U16
+}
+
+export function serializeTdpCoinbaseOutputConstraints(msg: Sv2TdpCoinbaseOutputConstraints): Buffer {
+  const w = new BufferWriter();
+  w.writeU32(msg.coinbaseOutputMaxAdditionalSize);
+  w.writeU16(msg.coinbaseOutputMaxAdditionalSigops);
+  return w.toBuffer();
+}
+
+export function deserializeTdpCoinbaseOutputConstraints(reader: BufferReader): Sv2TdpCoinbaseOutputConstraints {
+  return {
+    coinbaseOutputMaxAdditionalSize: reader.readU32(),
+    coinbaseOutputMaxAdditionalSigops: reader.readU16(),
+  };
+}
+
+// ── NewTemplate (0x71) ─────────────────────────────────────────────
+
+export interface Sv2TdpNewTemplate {
+  templateId: bigint;              // U64
+  futureTemplate: boolean;         // BOOL
+  version: number;                 // U32
+  coinbaseTxVersion: number;       // U32
+  coinbasePrefix: Buffer;          // B0_255
+  coinbaseTxInputSequence: number; // U32
+  coinbaseTxValueRemaining: bigint; // U64
+  coinbaseTxOutputsCount: number;  // U32
+  coinbaseTxOutputs: Buffer;       // B0_64K (serialized outputs)
+  coinbaseTxLocktime: number;      // U32
+  merklePath: Buffer[];            // SEQ0_255<U256>
+}
+
+export function serializeTdpNewTemplate(msg: Sv2TdpNewTemplate): Buffer {
+  const w = new BufferWriter();
+  w.writeU64(msg.templateId);
+  w.writeBool(msg.futureTemplate);
+  w.writeU32(msg.version);
+  w.writeU32(msg.coinbaseTxVersion);
+  w.writeB0_255(msg.coinbasePrefix);
+  w.writeU32(msg.coinbaseTxInputSequence);
+  w.writeU64(msg.coinbaseTxValueRemaining);
+  w.writeU32(msg.coinbaseTxOutputsCount);
+  w.writeB0_64K(msg.coinbaseTxOutputs);
+  w.writeU32(msg.coinbaseTxLocktime);
+  w.writeSeq0_255(msg.merklePath, (writer, hash) => writer.writeU256(hash));
+  return w.toBuffer();
+}
+
+export function deserializeTdpNewTemplate(reader: BufferReader): Sv2TdpNewTemplate {
+  return {
+    templateId: reader.readU64(),
+    futureTemplate: reader.readBool(),
+    version: reader.readU32(),
+    coinbaseTxVersion: reader.readU32(),
+    coinbasePrefix: reader.readB0_255(),
+    coinbaseTxInputSequence: reader.readU32(),
+    coinbaseTxValueRemaining: reader.readU64(),
+    coinbaseTxOutputsCount: reader.readU32(),
+    coinbaseTxOutputs: reader.readB0_64K(),
+    coinbaseTxLocktime: reader.readU32(),
+    merklePath: reader.readSeq0_255((r) => r.readU256()),
+  };
+}
+
+// ── SetNewPrevHash (0x72) ──────────────────────────────────────────
+
+export interface Sv2TdpSetNewPrevHash {
+  templateId: bigint;     // U64
+  prevHash: Buffer;       // U256
+  headerTimestamp: number; // U32
+  nBits: number;          // U32
+  target: Buffer;         // U256
+}
+
+export function serializeTdpSetNewPrevHash(msg: Sv2TdpSetNewPrevHash): Buffer {
+  const w = new BufferWriter();
+  w.writeU64(msg.templateId);
+  w.writeU256(msg.prevHash);
+  w.writeU32(msg.headerTimestamp);
+  w.writeU32(msg.nBits);
+  w.writeU256(msg.target);
+  return w.toBuffer();
+}
+
+export function deserializeTdpSetNewPrevHash(reader: BufferReader): Sv2TdpSetNewPrevHash {
+  return {
+    templateId: reader.readU64(),
+    prevHash: reader.readU256(),
+    headerTimestamp: reader.readU32(),
+    nBits: reader.readU32(),
+    target: reader.readU256(),
+  };
+}
+
+// ── RequestTransactionData (0x73) ──────────────────────────────────
+
+export interface Sv2TdpRequestTransactionData {
+  templateId: bigint; // U64
+}
+
+export function serializeTdpRequestTransactionData(msg: Sv2TdpRequestTransactionData): Buffer {
+  const w = new BufferWriter();
+  w.writeU64(msg.templateId);
+  return w.toBuffer();
+}
+
+export function deserializeTdpRequestTransactionData(reader: BufferReader): Sv2TdpRequestTransactionData {
+  return {
+    templateId: reader.readU64(),
+  };
+}
+
+// ── RequestTransactionData.Success (0x74) ──────────────────────────
+
+export interface Sv2TdpRequestTransactionDataSuccess {
+  templateId: bigint;        // U64
+  excessData: Buffer;        // B0_64K
+  transactionList: Buffer[]; // SEQ0_64K<B0_16M>
+}
+
+export function serializeTdpRequestTransactionDataSuccess(msg: Sv2TdpRequestTransactionDataSuccess): Buffer {
+  const w = new BufferWriter();
+  w.writeU64(msg.templateId);
+  w.writeB0_64K(msg.excessData);
+  w.writeSeq0_64K(msg.transactionList, (writer, tx) => writer.writeB0_16M(tx));
+  return w.toBuffer();
+}
+
+export function deserializeTdpRequestTransactionDataSuccess(reader: BufferReader): Sv2TdpRequestTransactionDataSuccess {
+  return {
+    templateId: reader.readU64(),
+    excessData: reader.readB0_64K(),
+    transactionList: reader.readSeq0_64K((r) => r.readB0_16M()),
+  };
+}
+
+// ── RequestTransactionData.Error (0x75) ────────────────────────────
+
+export interface Sv2TdpRequestTransactionDataError {
+  templateId: bigint;  // U64
+  errorCode: string;   // STR0_255
+}
+
+export function serializeTdpRequestTransactionDataError(msg: Sv2TdpRequestTransactionDataError): Buffer {
+  const w = new BufferWriter();
+  w.writeU64(msg.templateId);
+  w.writeStr0_255(msg.errorCode);
+  return w.toBuffer();
+}
+
+export function deserializeTdpRequestTransactionDataError(reader: BufferReader): Sv2TdpRequestTransactionDataError {
+  return {
+    templateId: reader.readU64(),
+    errorCode: reader.readStr0_255(),
+  };
+}
+
+// ── SubmitSolution (0x76) ──────────────────────────────────────────
+
+export interface Sv2TdpSubmitSolution {
+  templateId: bigint;     // U64
+  version: number;        // U32
+  headerTimestamp: number; // U32
+  headerNonce: number;    // U32
+  coinbaseTx: Buffer;     // B0_64K
+}
+
+export function serializeTdpSubmitSolution(msg: Sv2TdpSubmitSolution): Buffer {
+  const w = new BufferWriter();
+  w.writeU64(msg.templateId);
+  w.writeU32(msg.version);
+  w.writeU32(msg.headerTimestamp);
+  w.writeU32(msg.headerNonce);
+  w.writeB0_64K(msg.coinbaseTx);
+  return w.toBuffer();
+}
+
+export function deserializeTdpSubmitSolution(reader: BufferReader): Sv2TdpSubmitSolution {
+  return {
+    templateId: reader.readU64(),
+    version: reader.readU32(),
+    headerTimestamp: reader.readU32(),
+    headerNonce: reader.readU32(),
+    coinbaseTx: reader.readB0_64K(),
+  };
+}

src/services/bitcoin-rpc.service.ts

@@ -1,8 +1,8 @@
 import { Injectable, OnModuleInit } from '@nestjs/common';
 import { ConfigService } from '@nestjs/config';
-import { RPCClient } from 'rpc-bitcoin';
+import axios, { AxiosInstance } from 'axios';
 import { asyncScheduler, BehaviorSubject, delay, filter, from, interval, scheduled, shareReplay, startWith, Subject, switchMap } from 'rxjs';
-import { RpcBlockService } from 'src/ORM/rpc-block/rpc-block.service';
+import { RpcBlockService } from '../ORM/rpc-block/rpc-block.service';
 import * as zmq from 'zeromq';
 
 import { IBlockTemplate } from '../models/bitcoin-rpc/IBlockTemplate';
@@ -13,10 +13,11 @@ import * as PGPubsub from 'pg-pubsub';
 export class BitcoinRpcService implements OnModuleInit {
 
     
-    private client: RPCClient;
+    private client: AxiosInstance;
     private _newBlockTemplate$: BehaviorSubject<IBlockTemplate> = new BehaviorSubject(undefined);
     private pubsubInstance: PGPubsub;
     private resetTemplateInterval$ = new Subject<void>();
+    private rpcRequestId = 0;
 
     public miningInfo: IMiningInfo;
     public newBlockTemplate$ = this._newBlockTemplate$.pipe(filter(block => block != null), shareReplay({ refCount: true, bufferSize: 1 }));
@@ -39,9 +40,17 @@ export class BitcoinRpcService implements OnModuleInit {
         const port = parseInt(this.configService.get('BITCOIN_RPC_PORT'));
         const timeout = parseInt(this.configService.get('BITCOIN_RPC_TIMEOUT'));
 
-        this.client = new RPCClient({ url, port, timeout, user, pass });
+        const baseURL = this.buildRpcUrl(url, port);
+        this.client = axios.create({
+            baseURL,
+            timeout,
+            auth: {
+                username: user,
+                password: pass
+            }
+        });
 
-        this.client.getrpcinfo().then((res) => {
+        this.callRpc('getrpcinfo').then((res) => {
             console.log('Bitcoin RPC connected');
         }, () => {
             console.error('Could not reach RPC host');
@@ -109,13 +118,13 @@ export class BitcoinRpcService implements OnModuleInit {
 
         let blockTemplate: IBlockTemplate;
         while (blockTemplate == null) {
-            blockTemplate = await this.client.getblocktemplate({
-                template_request: {
+            blockTemplate = await this.callRpc<IBlockTemplate>('getblocktemplate', [
+                {
                     rules: ['segwit'],
                     mode: 'template',
                     capabilities: ['serverlist', 'proposal']
                 }
-            });
+            ]);
         }
 
         try {
@@ -131,7 +140,7 @@ export class BitcoinRpcService implements OnModuleInit {
 
     public async getMiningInfo(): Promise<IMiningInfo> {
         try {
-            return await this.client.getmininginfo();
+            return await this.callRpc<IMiningInfo>('getmininginfo');
         } catch (e) {
             console.error('Error getmininginfo', e.message);
             return null;
@@ -142,9 +151,7 @@ export class BitcoinRpcService implements OnModuleInit {
     public async SUBMIT_BLOCK(hexdata: string): Promise<string> {
         let response: string = 'unknown';
         try {
-            response = await this.client.submitblock({
-                hexdata
-            });
+            response = await this.callRpc<string>('submitblock', [hexdata]);
             if (response == null) {
                 response = 'SUCCESS!';
             }
@@ -158,5 +165,28 @@ export class BitcoinRpcService implements OnModuleInit {
         return response;
 
     }
-}
 
+    private async callRpc<T>(method: string, params: unknown[] = []): Promise<T> {
+        const response = await this.client.post('', {
+            jsonrpc: '1.0',
+            id: ++this.rpcRequestId,
+            method,
+            params
+        });
+
+        if (response.data.error != null) {
+            throw response.data.error;
+        }
+
+        return response.data.result;
+    }
+
+    private buildRpcUrl(url: string, port: number): string {
+        const normalizedUrl = /^https?:\/\//i.test(url) ? url : `http://${url}`;
+        const rpcUrl = new URL(normalizedUrl);
+        if (Number.isFinite(port) && port > 0) {
+            rpcUrl.port = port.toString();
+        }
+        return rpcUrl.toString();
+    }
+}

src/services/stratum-v1-jobs.service.spec.ts

@@ -0,0 +1,122 @@
+import { BehaviorSubject, firstValueFrom, skip } from 'rxjs';
+
+import { MockRecording1 } from '../../test/models/MockRecording1';
+import { IBlockTemplate } from '../models/bitcoin-rpc/IBlockTemplate';
+import { StratumV1JobsService } from './stratum-v1-jobs.service';
+
+describe('StratumV1JobsService', () => {
+    let blockTemplate$: BehaviorSubject<IBlockTemplate>;
+    let bitcoinRpcService: { newBlockTemplate$: any, miningInfo: { blocks: number } };
+    let service: StratumV1JobsService;
+    let consoleLogSpy: jest.SpyInstance;
+
+    const createTemplate = (height = MockRecording1.BLOCK_TEMPLATE.height): IBlockTemplate => ({
+        ...MockRecording1.BLOCK_TEMPLATE,
+        transactions: MockRecording1.BLOCK_TEMPLATE.transactions.map(tx => ({ ...tx })),
+        height
+    });
+
+    beforeEach(() => {
+        jest.useFakeTimers();
+        jest.setSystemTime(new Date(parseInt(MockRecording1.TIME, 16) * 1000));
+        consoleLogSpy = jest.spyOn(console, 'log').mockImplementation(() => undefined);
+
+        blockTemplate$ = new BehaviorSubject(createTemplate());
+        bitcoinRpcService = {
+            newBlockTemplate$: blockTemplate$.asObservable(),
+            miningInfo: { blocks: MockRecording1.BLOCK_TEMPLATE.height }
+        };
+        service = new StratumV1JobsService(bitcoinRpcService as any);
+    });
+
+    afterEach(() => {
+        consoleLogSpy.mockRestore();
+        jest.useRealTimers();
+    });
+
+    it('should create job templates from block templates', async () => {
+        const jobTemplate = await firstValueFrom(service.newMiningJob$);
+
+        expect(jobTemplate.blockData).toEqual(expect.objectContaining({
+            id: '1',
+            height: MockRecording1.BLOCK_TEMPLATE.height,
+            clearJobs: true,
+            coinbasevalue: MockRecording1.BLOCK_TEMPLATE.coinbasevalue
+        }));
+        expect(jobTemplate.merkle_branch.length).toBeGreaterThan(0);
+        expect(jobTemplate.block.transactions[0].ins[0].witness[0]).toHaveLength(32);
+        expect(service.getJobTemplateById('1')).toBe(jobTemplate);
+    });
+
+    it('should clear jobs when the block height changes', async () => {
+        const firstTemplate = await firstValueFrom(service.newMiningJob$);
+        service.addJob({ jobId: 'old-job', creation: Date.now() } as any);
+
+        bitcoinRpcService.miningInfo.blocks = MockRecording1.BLOCK_TEMPLATE.height + 1;
+        const nextTemplate = firstValueFrom(service.newMiningJob$.pipe(skip(1)));
+        blockTemplate$.next(createTemplate(MockRecording1.BLOCK_TEMPLATE.height + 1));
+        const jobTemplate = await nextTemplate;
+
+        expect(jobTemplate.blockData.clearJobs).toBe(true);
+        expect(service.getJobById('old-job')).toBeUndefined();
+        expect(service.getJobTemplateById(firstTemplate.blockData.id)).toBeUndefined();
+        expect(service.getJobTemplateById(jobTemplate.blockData.id)).toBe(jobTemplate);
+    });
+
+    it('should skip identical non-clean template refreshes', async () => {
+        await firstValueFrom(service.newMiningJob$);
+
+        blockTemplate$.next(createTemplate());
+
+        expect(service.latestJobTemplateId).toBe(2);
+        expect(Object.keys(service.blocks)).toHaveLength(1);
+    });
+
+    it('should emit when transaction identity changes without changing transaction count', async () => {
+        await firstValueFrom(service.newMiningJob$);
+
+        const reorderedTemplate = createTemplate();
+        reorderedTemplate.transactions = [
+            reorderedTemplate.transactions[1],
+            reorderedTemplate.transactions[0],
+            ...reorderedTemplate.transactions.slice(2)
+        ];
+
+        const nextTemplate = firstValueFrom(service.newMiningJob$.pipe(skip(1)));
+        blockTemplate$.next(reorderedTemplate);
+        const jobTemplate = await nextTemplate;
+
+        expect(jobTemplate.blockData.clearJobs).toBe(false);
+        expect(jobTemplate.blockData.id).toBe('2');
+        expect(service.getJobTemplateById(jobTemplate.blockData.id)).toBe(jobTemplate);
+    });
+
+    it('should age old jobs and templates after five minutes', async () => {
+        await firstValueFrom(service.newMiningJob$);
+        const oldCreation = Date.now() - (1000 * 60 * 11);
+        service.jobs['old-job'] = { jobId: 'old-job', creation: oldCreation } as any;
+        service.blocks['old-template'] = {
+            blockData: { creation: oldCreation }
+        } as any;
+
+        bitcoinRpcService.miningInfo.blocks = MockRecording1.BLOCK_TEMPLATE.height;
+        jest.setSystemTime(new Date(Date.now() + 1000));
+        const nextTemplate = firstValueFrom(service.newMiningJob$.pipe(skip(1)));
+        blockTemplate$.next(createTemplate());
+        const jobTemplate = await nextTemplate;
+
+        expect(jobTemplate.blockData.clearJobs).toBe(false);
+        expect(service.getJobById('old-job')).toBeUndefined();
+        expect(service.getJobTemplateById('old-template')).toBeUndefined();
+        expect(service.getJobTemplateById(jobTemplate.blockData.id)).toBe(jobTemplate);
+    });
+
+    it('should increment job ids when jobs are added', () => {
+        expect(service.getNextId()).toBe('1');
+
+        service.addJob({ jobId: '1', creation: Date.now() } as any);
+
+        expect(service.getNextId()).toBe('2');
+        expect(service.getJobById('1')).toEqual(expect.objectContaining({ jobId: '1' }));
+    });
+});

src/services/stratum-v1-jobs.service.ts

@@ -31,6 +31,7 @@ export class StratumV1JobsService {
     public blocks: { [id: number]: IJobTemplate } = {};
 
     private lastBlockHeight = 0;
+    private lastWorkSignature: string;
 
     constructor(
         private readonly bitcoinRpcService: BitcoinRpcService
@@ -53,13 +54,29 @@ export class StratumV1JobsService {
                 }
 
                 const currentTime = Math.floor(new Date().getTime() / 1000);
+                const timestamp = blockTemplate.mintime > currentTime ? blockTemplate.mintime : currentTime;
+                const workSignature = [
+                    blockTemplate.previousblockhash,
+                    blockTemplate.version,
+                    blockTemplate.bits,
+                    timestamp,
+                    blockTemplate.height,
+                    blockTemplate.coinbasevalue,
+                    ...blockTemplate.transactions.map(tx => tx.hash ?? tx.txid ?? tx.data)
+                ].join('|');
+
+                if (!clearJobs && workSignature === this.lastWorkSignature) {
+                    return null;
+                }
+                this.lastWorkSignature = workSignature;
+
                 return {
                     version: blockTemplate.version,
                     bits: parseInt(blockTemplate.bits, 16),
                     prevHash: this.convertToLittleEndian(blockTemplate.previousblockhash),
                     transactions: blockTemplate.transactions.map(t => bitcoinjs.Transaction.fromHex(t.data)),
                     coinbasevalue: blockTemplate.coinbasevalue,
-                    timestamp: blockTemplate.mintime > currentTime ? blockTemplate.mintime : currentTime,
+                    timestamp,
                     networkDifficulty: this.calculateNetworkDifficulty(parseInt(blockTemplate.bits, 16)),
                     clearJobs,
                     height: blockTemplate.height
@@ -178,5 +195,4 @@ export class StratumV1JobsService {
         return this.latestJobId.toString(16);
     }
 
-
 }

src/services/stratum-v1.service.spec.ts

@@ -0,0 +1,203 @@
+import { StratumV1Service } from './stratum-v1.service';
+
+describe('StratumV1Service', () => {
+    const originalMaster = process.env.MASTER;
+    const originalStratumPorts = process.env.STRATUM_PORTS;
+    const originalStratumSecure = process.env.STRATUM_SECURE;
+    const originalSecureStratumPorts = process.env.SECURE_STRATUM_PORTS;
+    const originalBackpressureEnabled = process.env.STRATUM_BACKPRESSURE_ENABLED;
+    const originalMaxConnectionsPerListener = process.env.STRATUM_MAX_CONNECTIONS_PER_LISTENER;
+    const originalTlsHandshakeTimeoutMs = process.env.STRATUM_TLS_HANDSHAKE_TIMEOUT_MS;
+
+    let service: StratumV1Service;
+    let clientService;
+    let stratumV2Service;
+    let consoleLogSpy: jest.SpyInstance;
+    let consoleWarnSpy: jest.SpyInstance;
+
+    beforeEach(() => {
+        jest.useFakeTimers();
+        clientService = {
+            deleteAll: jest.fn().mockResolvedValue(undefined)
+        };
+        stratumV2Service = {
+            ensureInitialized: jest.fn().mockResolvedValue(undefined),
+            createClient: jest.fn()
+        };
+        service = new StratumV1Service(
+            {} as any,
+            clientService,
+            {} as any,
+            {} as any,
+            {} as any,
+            {} as any,
+            {} as any,
+            {} as any,
+            stratumV2Service as any
+        );
+        consoleLogSpy = jest.spyOn(console, 'log').mockImplementation(() => undefined);
+        consoleWarnSpy = jest.spyOn(console, 'warn').mockImplementation(() => undefined);
+    });
+
+    afterEach(() => {
+        restoreEnv('MASTER', originalMaster);
+        restoreEnv('STRATUM_PORTS', originalStratumPorts);
+        restoreEnv('STRATUM_SECURE', originalStratumSecure);
+        restoreEnv('SECURE_STRATUM_PORTS', originalSecureStratumPorts);
+        restoreEnv('STRATUM_BACKPRESSURE_ENABLED', originalBackpressureEnabled);
+        restoreEnv('STRATUM_MAX_CONNECTIONS_PER_LISTENER', originalMaxConnectionsPerListener);
+        restoreEnv('STRATUM_TLS_HANDSHAKE_TIMEOUT_MS', originalTlsHandshakeTimeoutMs);
+        consoleLogSpy.mockRestore();
+        consoleWarnSpy.mockRestore();
+        jest.useRealTimers();
+    });
+
+    it('should skip Stratum listeners in the master process', async () => {
+        process.env.MASTER = 'true';
+        const startSocketServerSpy = jest.spyOn(service as any, 'startSocketServer');
+        const startSecureSocketServerSpy = jest.spyOn(service as any, 'startSecureSocketServer');
+
+        await service.onModuleInit();
+        jest.runOnlyPendingTimers();
+
+        expect(clientService.deleteAll).toHaveBeenCalled();
+        expect(startSocketServerSpy).not.toHaveBeenCalled();
+        expect(startSecureSocketServerSpy).not.toHaveBeenCalled();
+        expect(consoleLogSpy).toHaveBeenCalledWith('Master process skipping Stratum socket listeners');
+    });
+
+    it('should start Stratum listeners in worker processes', async () => {
+        process.env.MASTER = 'false';
+        process.env.STRATUM_PORTS = '3333,3334';
+        process.env.STRATUM_SECURE = 'true';
+        process.env.SECURE_STRATUM_PORTS = '4333';
+        const startSocketServerSpy = jest.spyOn(service as any, 'startSocketServer').mockImplementation(() => undefined);
+        const startSecureSocketServerSpy = jest.spyOn(service as any, 'startSecureSocketServer').mockImplementation(() => undefined);
+
+        await service.onModuleInit();
+        jest.advanceTimersByTime(10000);
+
+        expect(clientService.deleteAll).not.toHaveBeenCalled();
+        expect(startSocketServerSpy).toHaveBeenCalledWith(3333);
+        expect(startSocketServerSpy).toHaveBeenCalledWith(3334);
+        expect(startSecureSocketServerSpy).toHaveBeenCalledWith(4333);
+    });
+
+    it('should pause listeners when worker backpressure is high', () => {
+        const close = jest.fn((callback?: (error?: Error) => void) => callback?.());
+        (service as any).listeners.push({
+            port: 3333,
+            secure: false,
+            server: { close },
+            paused: false
+        });
+        jest.spyOn(service as any, 'getEventLoopP95Ms').mockReturnValue(5000);
+        jest.spyOn(service as any, 'getBackpressureEventLoopP95Ms').mockReturnValue(2000);
+
+        (service as any).checkBackpressure();
+
+        expect(close).toHaveBeenCalled();
+        expect((service as any).listeners[0].paused).toBe(true);
+        expect((service as any).listeners[0].server).toBeNull();
+        expect(consoleWarnSpy).toHaveBeenCalledWith(expect.stringContaining('Pausing Stratum accepts'));
+    });
+
+    it('should resume listeners after consecutive healthy backpressure checks', () => {
+        (service as any).listeners.push({
+            port: 3333,
+            secure: false,
+            server: null,
+            paused: true
+        });
+        jest.spyOn(service as any, 'getEventLoopP95Ms').mockReturnValue(50);
+        jest.spyOn(service as any, 'getBackpressureEventLoopP95Ms').mockReturnValue(2000);
+        jest.spyOn(service as any, 'getBackpressureResumeEventLoopP95Ms').mockReturnValue(250);
+        jest.spyOn(service as any, 'getBackpressureResumeRssMb').mockReturnValue(Number.MAX_SAFE_INTEGER);
+        jest.spyOn(service as any, 'getBackpressureHealthyChecks').mockReturnValue(2);
+        const listenSpy = jest.spyOn(service as any, 'listen').mockImplementation((listener: any) => {
+            listener.server = {};
+            listener.paused = false;
+        });
+
+        (service as any).checkBackpressure();
+        expect(listenSpy).not.toHaveBeenCalled();
+
+        (service as any).checkBackpressure();
+
+        expect(listenSpy).toHaveBeenCalledWith((service as any).listeners[0]);
+        expect((service as any).listeners[0].paused).toBe(false);
+        expect(consoleWarnSpy).toHaveBeenCalledWith(expect.stringContaining('Resuming Stratum accepts'));
+    });
+
+    it('should cap listener connections and drop excess cluster connections', () => {
+        process.env.STRATUM_MAX_CONNECTIONS_PER_LISTENER = '250';
+        const server = {} as any;
+
+        (service as any).configureConnectionLimit(server);
+
+        expect(server.maxConnections).toBe(250);
+        expect(server.dropMaxConnection).toBe(true);
+    });
+
+    it('should allow high-volume pools by default', () => {
+        delete process.env.STRATUM_MAX_CONNECTIONS_PER_LISTENER;
+
+        expect((service as any).getMaxConnectionsPerListener()).toBe(10000);
+    });
+
+    it('should use an explicit TLS handshake timeout', () => {
+        process.env.STRATUM_TLS_HANDSHAKE_TIMEOUT_MS = '5000';
+
+        expect((service as any).getTlsHandshakeTimeoutMs()).toBe(5000);
+    });
+
+    it('should detect JSON-RPC as Stratum V1', () => {
+        const firstChunk = Buffer.from('{"id":1,"method":"mining.subscribe","params":[]}\n');
+
+        expect((service as any).detectProtocol(firstChunk)).toBe('v1');
+    });
+
+    it('should detect JSON-RPC as Stratum V1 even with non-printable trailing bytes', () => {
+        const firstChunk = Buffer.concat([
+            Buffer.from('{"id": 1, "method": "mining.subscribe", "params": []}\n'),
+            Buffer.from([0x00, 0xff])
+        ]);
+
+        expect((service as any).detectProtocol(firstChunk)).toBe('v1');
+    });
+
+    it('should detect binary Noise traffic as Stratum V2', () => {
+        const firstChunk = Buffer.concat([
+            Buffer.from([0x01, 0x02, 0x03, 0x04]),
+            Buffer.alloc(60, 0xaa)
+        ]);
+
+        expect((service as any).detectProtocol(firstChunk)).toBe('v2');
+    });
+
+    it('should reject recognizable TLS client hello on the unified plain stratum port', () => {
+        expect((service as any).detectProtocol(Buffer.from([0x16, 0x03, 0x01]))).toBeNull();
+    });
+
+    it('should route binary data that only shares a TLS first byte to Stratum V2', () => {
+        expect((service as any).detectProtocol(Buffer.from([0x16, 0xaa, 0xbb]))).toBe('v2');
+    });
+
+    it('should not route plaintext PROXY protocol headers to Stratum V2', () => {
+        const firstChunk = Buffer.from('PROXY TCP4 203.0.113.10 192.0.2.10 54321 3333\\r\\n');
+
+        expect((service as any).detectProtocol(firstChunk)).toBeNull();
+    });
+
+    it('should not route malformed plaintext to Stratum V2', () => {
+        expect((service as any).detectProtocol(Buffer.from('mining.subscribe\\n'))).toBeNull();
+    });
+
+    function restoreEnv(key: string, value: string | undefined) {
+        if (value == null) {
+            delete process.env[key];
+            return;
+        }
+        process.env[key] = value;
+    }
+});

src/services/stratum-v1.service.ts

@@ -1,8 +1,10 @@
 import { Injectable, OnModuleInit } from '@nestjs/common';
 import { ConfigService } from '@nestjs/config';
 import { Server, Socket } from 'net';
+import { monitorEventLoopDelay } from 'perf_hooks';
 
 import { StratumV1Client } from '../models/StratumV1Client';
+import { StratumV2Client } from '../models/StratumV2Client';
 import { AddressSettingsService } from '../ORM/address-settings/address-settings.service';
 import { BlocksService } from '../ORM/blocks/blocks.service';
 import { ClientStatisticsService } from '../ORM/client-statistics/client-statistics.service';
@@ -10,11 +12,28 @@ import { ClientService } from '../ORM/client/client.service';
 import { BitcoinRpcService } from './bitcoin-rpc.service';
 import { NotificationService } from './notification.service';
 import { StratumV1JobsService } from './stratum-v1-jobs.service';
+import { StratumV2Service } from './stratum-v2.service';
 
 import { readFileSync } from 'fs';
 import { TlsOptions, TLSSocket, createServer } from 'tls';
 import * as path from 'path';
 
+interface StratumListenerState {
+    port: number;
+    secure: boolean;
+    server: Server | null;
+    paused: boolean;
+}
+
+const DEFAULT_BACKPRESSURE_CHECK_INTERVAL_MS = 5000;
+const DEFAULT_BACKPRESSURE_EVENT_LOOP_P95_MS = 2000;
+const DEFAULT_BACKPRESSURE_EVENT_LOOP_RESUME_P95_MS = 250;
+const DEFAULT_BACKPRESSURE_RSS_MB = 2500;
+const DEFAULT_BACKPRESSURE_RESUME_RSS_MB = 2000;
+const DEFAULT_BACKPRESSURE_HEALTHY_CHECKS = 3;
+const DEFAULT_MAX_CONNECTIONS_PER_LISTENER = 10000;
+const DEFAULT_TLS_HANDSHAKE_TIMEOUT_MS = 10000;
+
 
 
 @Injectable()
@@ -24,6 +43,10 @@ export class StratumV1Service implements OnModuleInit {
     private emptySocket = 0;
     private normalClosure = 0;
     private errorClosure = 0;
+    private readonly listeners: StratumListenerState[] = [];
+    private readonly eventLoopDelay = monitorEventLoopDelay({ resolution: 20 });
+    private backpressureMonitor: NodeJS.Timeout | null = null;
+    private healthyBackpressureChecks = 0;
 
     constructor(
         private readonly bitcoinRpcService: BitcoinRpcService,
@@ -33,7 +56,8 @@ export class StratumV1Service implements OnModuleInit {
         private readonly blocksService: BlocksService,
         private readonly configService: ConfigService,
         private readonly stratumV1JobsService: StratumV1JobsService,
-        private readonly addressSettingsService: AddressSettingsService
+        private readonly addressSettingsService: AddressSettingsService,
+        private readonly stratumV2Service: StratumV2Service
     ) {
 
     }
@@ -42,6 +66,8 @@ export class StratumV1Service implements OnModuleInit {
 
         if (process.env.MASTER == 'true') {
             await this.clientService.deleteAll();
+            console.log('Master process skipping Stratum socket listeners');
+            return;
         }
 
         // wait for all the other processes to init for an even connection distribution 
@@ -64,28 +90,32 @@ export class StratumV1Service implements OnModuleInit {
             this.errorClosure = 0;
         }, 1000 * 60);
 
+        this.startBackpressureMonitor();
+
     }
 
     private startSocketServer(port: number) {
+        const listener: StratumListenerState = {
+            port,
+            secure: false,
+            server: null,
+            paused: false
+        };
+        this.listeners.push(listener);
+        this.listen(listener);
+    }
+
+    private createSocketServer(): Server {
         const server = new Server(async (socket: Socket) => {
             // Set 15-minute timeout
             socket.setTimeout(1000 * 60 * 15);
 
-            const client = new StratumV1Client(
-                socket,
-                this.stratumV1JobsService,
-                this.bitcoinRpcService,
-                this.clientService,
-                this.clientStatisticsService,
-                this.notificationService,
-                this.blocksService,
-                this.configService,
-                this.addressSettingsService
-            );
+            let client: StratumV1Client | StratumV2Client = null;
+            let protocol: 'v1' | 'v2' | null = null;
 
             // Unified cleanup function
             const cleanup = async (reason: string) => {
-                if (client.extraNonceAndSessionId != null) {
+                if (client != null && (protocol === 'v2' || (client as StratumV1Client).extraNonceAndSessionId != null)) {
                     await client.destroy();
                     if (reason == 'Error') {
                         this.errorClosure++;
@@ -119,8 +149,30 @@ export class StratumV1Service implements OnModuleInit {
                 await cleanup("Error");
             });
 
-            //
+            socket.once('data', async (firstChunk: Buffer) => {
+                try {
+                    protocol = this.detectProtocol(firstChunk);
+                    if (protocol === 'v1') {
+                        client = this.createV1Client(socket);
+                        socket.emit('data', firstChunk);
+                        return;
+                    }
 
+                    if (protocol === 'v2') {
+                        await this.stratumV2Service.ensureInitialized();
+                        client = this.stratumV2Service.createClient(socket, firstChunk);
+                        return;
+                    }
+
+                    if (!socket.destroyed) {
+                        socket.end();
+                        socket.destroy();
+                    }
+                } catch (error) {
+                    console.error(`Protocol detection failed: ${error.message}`);
+                    await cleanup('Error');
+                }
+            });
 
         });
 
@@ -128,14 +180,37 @@ export class StratumV1Service implements OnModuleInit {
         server.on('error', (err) => {
             console.error(`Server error: ${err.message}`);
         });
+        this.configureConnectionLimit(server);
 
-        server.listen(port, () => {
-            console.log(`Stratum server is listening on port ${port}`);
-        });
+        return server;
+    }
 
+    private createV1Client(socket: Socket): StratumV1Client {
+        return new StratumV1Client(
+            socket,
+            this.stratumV1JobsService,
+            this.bitcoinRpcService,
+            this.clientService,
+            this.clientStatisticsService,
+            this.notificationService,
+            this.blocksService,
+            this.configService,
+            this.addressSettingsService
+        );
     }
 
     private startSecureSocketServer(port: number) {
+        const listener: StratumListenerState = {
+            port,
+            secure: true,
+            server: null,
+            paused: false
+        };
+        this.listeners.push(listener);
+        this.listen(listener);
+    }
+
+    private createSecureSocketServer(): Server {
 
         const currentDirectory = process.cwd();
         const keyPath = path.join(currentDirectory, 'secrets', 'key.pem');
@@ -144,23 +219,14 @@ export class StratumV1Service implements OnModuleInit {
         const tlsOptions: TlsOptions = {
             key: readFileSync(keyPath),
             cert: readFileSync(certPath),
+            handshakeTimeout: this.getTlsHandshakeTimeoutMs()
         };
 
         const server = createServer(tlsOptions, async (socket: TLSSocket) => {
             // Set 15-minute timeout
             socket.setTimeout(1000 * 60 * 15);
 
-            const client = new StratumV1Client(
-                socket,
-                this.stratumV1JobsService,
-                this.bitcoinRpcService,
-                this.clientService,
-                this.clientStatisticsService,
-                this.notificationService,
-                this.blocksService,
-                this.configService,
-                this.addressSettingsService
-            );
+            const client = this.createV1Client(socket);
 
             const cleanup = async (reason: string) => {
                 if (client.extraNonceAndSessionId != null) {
@@ -200,12 +266,247 @@ export class StratumV1Service implements OnModuleInit {
         server.on('error', (err) => {
             console.error(`Server error: ${err.message}`);
         });
+        this.configureConnectionLimit(server);
 
-        server.listen(port, () => {
-            console.log(`Stratum TLS server is listening on port ${port}`);
+        return server;
+
+    }
+
+    private listen(listener: StratumListenerState) {
+        if (listener.server != null) {
+            return;
+        }
+
+        const server = listener.secure ? this.createSecureSocketServer() : this.createSocketServer();
+        listener.server = server;
+        listener.paused = false;
+
+        server.listen(listener.port, () => {
+            console.log(`${listener.secure ? 'Stratum TLS' : 'Stratum'} server is listening on port ${listener.port}`);
         });
+    }
+
+    private startBackpressureMonitor() {
+        if (this.isBackpressureDisabled() || this.backpressureMonitor != null) {
+            return;
+        }
+
+        this.eventLoopDelay.enable();
+        this.backpressureMonitor = setInterval(() => {
+            this.checkBackpressure();
+        }, this.getBackpressureCheckIntervalMs());
+    }
+
+    private checkBackpressure() {
+        const eventLoopP95Ms = this.getEventLoopP95Ms();
+        const rssMb = Math.round(process.memoryUsage().rss / 1024 / 1024);
+        const overloaded = eventLoopP95Ms >= this.getBackpressureEventLoopP95Ms()
+            || rssMb >= this.getBackpressureRssMb();
+        const paused = this.listeners.some(listener => listener.paused);
+
+        if (overloaded) {
+            this.healthyBackpressureChecks = 0;
+            if (!paused) {
+                this.pauseAccepting(eventLoopP95Ms, rssMb);
+            }
+            this.eventLoopDelay.reset();
+            return;
+        }
+
+        if (!paused) {
+            this.eventLoopDelay.reset();
+            return;
+        }
+
+        const healthy = eventLoopP95Ms <= this.getBackpressureResumeEventLoopP95Ms()
+            && rssMb <= this.getBackpressureResumeRssMb();
+        if (!healthy) {
+            this.healthyBackpressureChecks = 0;
+            this.eventLoopDelay.reset();
+            return;
+        }
+
+        this.healthyBackpressureChecks++;
+        if (this.healthyBackpressureChecks >= this.getBackpressureHealthyChecks()) {
+            this.resumeAccepting(eventLoopP95Ms, rssMb);
+            this.healthyBackpressureChecks = 0;
+        }
+
+        this.eventLoopDelay.reset();
+    }
+
+    private pauseAccepting(eventLoopP95Ms: number, rssMb: number) {
+        console.warn(`Pausing Stratum accepts: eventLoopP95Ms=${eventLoopP95Ms}, rssMb=${rssMb}`);
+        for (const listener of this.listeners) {
+            if (listener.paused || listener.server == null) {
+                continue;
+            }
+
+            const server = listener.server;
+            listener.server = null;
+            listener.paused = true;
+            server.close((error) => {
+                if (error != null) {
+                    console.error(`Error while pausing Stratum listener on port ${listener.port}: ${error.message}`);
+                }
+            });
+        }
+    }
+
+    private resumeAccepting(eventLoopP95Ms: number, rssMb: number) {
+        console.warn(`Resuming Stratum accepts: eventLoopP95Ms=${eventLoopP95Ms}, rssMb=${rssMb}`);
+        for (const listener of this.listeners) {
+            if (!listener.paused || listener.server != null) {
+                continue;
+            }
+
+            this.listen(listener);
+        }
+    }
+
+    private getEventLoopP95Ms() {
+        return Math.round(this.eventLoopDelay.percentile(95) / 1e6);
+    }
+
+    private isBackpressureDisabled() {
+        return process.env.STRATUM_BACKPRESSURE_ENABLED?.toLowerCase() === 'false';
+    }
+
+    private getBackpressureCheckIntervalMs() {
+        return this.getPositiveIntegerEnv('STRATUM_BACKPRESSURE_CHECK_INTERVAL_MS', DEFAULT_BACKPRESSURE_CHECK_INTERVAL_MS);
+    }
+
+    private getBackpressureEventLoopP95Ms() {
+        return this.getPositiveIntegerEnv('STRATUM_BACKPRESSURE_EVENT_LOOP_P95_MS', DEFAULT_BACKPRESSURE_EVENT_LOOP_P95_MS);
+    }
+
+    private getBackpressureResumeEventLoopP95Ms() {
+        return this.getPositiveIntegerEnv('STRATUM_BACKPRESSURE_EVENT_LOOP_RESUME_P95_MS', DEFAULT_BACKPRESSURE_EVENT_LOOP_RESUME_P95_MS);
+    }
+
+    private getBackpressureRssMb() {
+        return this.getPositiveIntegerEnv('STRATUM_BACKPRESSURE_RSS_MB', DEFAULT_BACKPRESSURE_RSS_MB);
+    }
+
+    private getBackpressureResumeRssMb() {
+        return this.getPositiveIntegerEnv('STRATUM_BACKPRESSURE_RESUME_RSS_MB', DEFAULT_BACKPRESSURE_RESUME_RSS_MB);
+    }
+
+    private getBackpressureHealthyChecks() {
+        return this.getPositiveIntegerEnv('STRATUM_BACKPRESSURE_HEALTHY_CHECKS', DEFAULT_BACKPRESSURE_HEALTHY_CHECKS);
+    }
+
+    private configureConnectionLimit(server: Server) {
+        server.maxConnections = this.getMaxConnectionsPerListener();
+        (server as Server & { dropMaxConnection: boolean }).dropMaxConnection = true;
+    }
+
+    private getMaxConnectionsPerListener() {
+        return this.getPositiveIntegerEnv('STRATUM_MAX_CONNECTIONS_PER_LISTENER', DEFAULT_MAX_CONNECTIONS_PER_LISTENER);
+    }
+
+    private getTlsHandshakeTimeoutMs() {
+        return this.getPositiveIntegerEnv('STRATUM_TLS_HANDSHAKE_TIMEOUT_MS', DEFAULT_TLS_HANDSHAKE_TIMEOUT_MS);
+    }
+
+    private detectProtocol(firstChunk: Buffer): 'v1' | 'v2' | null {
+        if (firstChunk.length === 0) {
+            return null;
+        }
+
+        if (this.looksLikeJsonRpc(firstChunk)) {
+            return 'v1';
+        }
+
+        // TLS ClientHello. Secure SV1 remains on SECURE_STRATUM_PORTS.
+        if (this.looksLikeTlsClientHello(firstChunk)) {
+            return null;
+        }
+
+        // HTTP on a stratum port is not supported in this branch.
+        if (this.looksLikeHttpRequest(firstChunk)) {
+            return null;
+        }
+
+        // Plaintext that is not JSON-RPC is not a valid SV2 Noise Act 1. This
+        // catches PROXY-protocol lines, SSH banners, and malformed SV1 clients
+        // before they get misrouted into the SV2 decrypt path.
+        if (this.looksLikePlaintext(firstChunk)) {
+            return null;
+        }
+
+        return 'v2';
+    }
+
+    private looksLikeJsonRpc(firstChunk: Buffer): boolean {
+        let firstNonWhitespace = -1;
+        for (let i = 0; i < firstChunk.length; i++) {
+            const byte = firstChunk[i];
+            if (byte === 0x20 || byte === 0x09 || byte === 0x0a || byte === 0x0d) {
+                continue;
+            }
+            firstNonWhitespace = i;
+            break;
+        }
+
+        if (firstNonWhitespace < 0 || firstChunk[firstNonWhitespace] !== 0x7b) {
+            return false;
+        }
+
+        const jsonPrefix = firstChunk
+            .subarray(firstNonWhitespace, Math.min(firstChunk.length, firstNonWhitespace + 256))
+            .toString('utf8');
+        if (jsonPrefix.includes('"method"') || jsonPrefix.includes('"id"')) {
+            return true;
+        }
+
+        for (const byte of firstChunk) {
+            const isWhitespace = byte === 0x09 || byte === 0x0a || byte === 0x0d;
+            const isPrintableAscii = byte >= 0x20 && byte <= 0x7e;
+            if (!isWhitespace && !isPrintableAscii) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private looksLikeTlsClientHello(firstChunk: Buffer): boolean {
+        return firstChunk.length >= 3
+            && firstChunk[0] === 0x16
+            && firstChunk[1] === 0x03;
+    }
+
+    private looksLikeHttpRequest(firstChunk: Buffer): boolean {
+        const prefix = firstChunk.subarray(0, Math.min(firstChunk.length, 8)).toString('ascii').toUpperCase();
+        return prefix.startsWith('GET ')
+            || prefix.startsWith('POST ')
+            || prefix.startsWith('PUT ')
+            || prefix.startsWith('PATCH ')
+            || prefix.startsWith('HEAD ')
+            || prefix.startsWith('OPTIONS ');
+    }
+
+    private looksLikePlaintext(firstChunk: Buffer): boolean {
+        for (const byte of firstChunk) {
+            const isWhitespace = byte === 0x09 || byte === 0x0a || byte === 0x0d;
+            const isPrintableAscii = byte >= 0x20 && byte <= 0x7e;
+            if (!isWhitespace && !isPrintableAscii) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private getPositiveIntegerEnv(key: string, fallback: number) {
+        const configured = parseInt(process.env[key], 10);
+        if (Number.isFinite(configured) && configured > 0) {
+            return configured;
+        }
+        return fallback;
 
     }
 
 
-}
+}

src/services/stratum-v2.service.ts

@@ -0,0 +1,211 @@
+import { Injectable, OnModuleInit } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import * as crypto from 'crypto';
+import { Server, Socket } from 'net';
+
+import { AddressSettingsService } from '../ORM/address-settings/address-settings.service';
+import { BlocksService } from '../ORM/blocks/blocks.service';
+import { ClientStatisticsService } from '../ORM/client-statistics/client-statistics.service';
+import { ClientService } from '../ORM/client/client.service';
+import { StratumV2Client } from '../models/StratumV2Client';
+import { encodeSv2AuthorityPublicKey } from '../models/sv2/sv2-authority-key';
+import { Sv2ExtranonceManager } from '../models/sv2/sv2-extranonce-manager';
+import {
+    createSignatureNoiseMessage,
+    generateServerKeypair,
+    Sv2NoiseConfig,
+    Sv2ServerKeypair,
+    xOnlyPubKeyFromPriv,
+} from '../models/sv2/sv2-noise';
+import { BitcoinRpcService } from './bitcoin-rpc.service';
+import { NotificationService } from './notification.service';
+import { StratumV1JobsService } from './stratum-v1-jobs.service';
+
+@Injectable()
+export class StratumV2Service implements OnModuleInit {
+    private readonly servers: Server[] = [];
+    private authorityPrivKey: Buffer;
+    private authorityPublicKeyXOnly: Buffer;
+    private authorityKeyConfigured = false;
+    private serverKeypair: Sv2ServerKeypair;
+    private noiseConfig: Sv2NoiseConfig;
+    private channelIdCounter = 1;
+    private readonly extranonceManager = new Sv2ExtranonceManager();
+
+    constructor(
+        private readonly bitcoinRpcService: BitcoinRpcService,
+        private readonly clientService: ClientService,
+        private readonly clientStatisticsService: ClientStatisticsService,
+        private readonly notificationService: NotificationService,
+        private readonly blocksService: BlocksService,
+        private readonly configService: ConfigService,
+        private readonly stratumV1JobsService: StratumV1JobsService,
+        private readonly addressSettingsService: AddressSettingsService,
+    ) {}
+
+    public async onModuleInit(): Promise<void> {
+        if (process.env.MASTER === 'true') {
+            return;
+        }
+
+        const ports = this.getPorts();
+        if (ports.length === 0) {
+            return;
+        }
+
+        await this.ensureInitialized();
+        ports.forEach(port => this.startSocketServer(port));
+    }
+
+    public async ensureInitialized(): Promise<void> {
+        if (this.noiseConfig != null) {
+            return;
+        }
+
+        await this.initializeNoiseConfig();
+    }
+
+    public createClient(socket: Socket, firstChunk: Buffer): StratumV2Client {
+        if (this.noiseConfig == null) {
+            throw new Error('Stratum V2 service is not initialized');
+        }
+
+        return new StratumV2Client(
+            socket,
+            firstChunk,
+            this,
+            this.stratumV1JobsService,
+            this.bitcoinRpcService,
+            this.clientService,
+            this.clientStatisticsService,
+            this.notificationService,
+            this.blocksService,
+            this.configService,
+            this.addressSettingsService,
+        );
+    }
+
+    public getNoiseConfig(): Sv2NoiseConfig {
+        return this.noiseConfig;
+    }
+
+    public async getPoolAuthorityPublicKey(): Promise<{ publicKey: string; configured: boolean }> {
+        await this.ensureInitialized();
+
+        return {
+            publicKey: encodeSv2AuthorityPublicKey(this.authorityPublicKeyXOnly),
+            configured: this.authorityKeyConfigured,
+        };
+    }
+
+    public getNextChannelId(): number {
+        return this.channelIdCounter++;
+    }
+
+    public generateExtranoncePrefix(): Buffer {
+        const prefix = Buffer.alloc(4);
+        prefix.writeUInt16BE(this.channelIdCounter & 0xffff, 0);
+        crypto.randomBytes(2).copy(prefix, 2);
+        return prefix;
+    }
+
+    public allocateExtendedExtranoncePrefix(channelId: number): Buffer {
+        return this.extranonceManager.allocate(channelId);
+    }
+
+    public releaseExtendedExtranoncePrefix(channelId: number): void {
+        this.extranonceManager.release(channelId);
+    }
+
+    public getExtendedMinerExtranonceSize(): number {
+        return this.extranonceManager.minerExtranonceSize;
+    }
+
+    private async initializeNoiseConfig(): Promise<void> {
+        const configuredAuthorityKey = this.configService.get<string>('SV2_AUTHORITY_PRIVKEY');
+        this.authorityKeyConfigured = configuredAuthorityKey?.length === 64;
+        this.authorityPrivKey = configuredAuthorityKey?.length === 64
+            ? Buffer.from(configuredAuthorityKey, 'hex')
+            : crypto.randomBytes(32);
+        this.authorityPublicKeyXOnly = xOnlyPubKeyFromPriv(this.authorityPrivKey);
+
+        if (!configuredAuthorityKey) {
+            console.warn('SV2_AUTHORITY_PRIVKEY is not set; generated an ephemeral SV2 authority key');
+        }
+
+        this.serverKeypair = await generateServerKeypair();
+        const now = Math.floor(Date.now() / 1000);
+        this.noiseConfig = {
+            staticKeypair: this.serverKeypair,
+            certificateMessage: createSignatureNoiseMessage(
+                this.authorityPrivKey,
+                xOnlyPubKeyFromPriv(this.serverKeypair.privateKey),
+                now - 3600,
+                now + 86400,
+            ),
+        };
+    }
+
+    private getPorts(): number[] {
+        const configuredPorts = this.configService.get<string>('STRATUM_V2_PORTS');
+        if (!configuredPorts?.trim()) {
+            return [];
+        }
+
+        const ports = configuredPorts
+            .split(',')
+            .map(port => parseInt(port.trim(), 10))
+            .filter(port => Number.isInteger(port) && port > 0 && port <= 65535);
+
+        return Array.from(new Set(ports));
+    }
+
+    private startSocketServer(port: number): void {
+        const server = new Server((socket: Socket) => {
+            socket.setTimeout(this.getSocketTimeoutMs());
+            socket.setNoDelay(true);
+
+            let client: StratumV2Client = null;
+
+            const closeSocket = () => {
+                if (client != null) {
+                    void client.destroy();
+                }
+                if (!socket.destroyed) {
+                    socket.destroy();
+                }
+            };
+
+            socket.once('data', (firstChunk: Buffer) => {
+                client = this.createClient(socket, firstChunk);
+            });
+
+            socket.on('timeout', closeSocket);
+            socket.on('error', (error: NodeJS.ErrnoException) => {
+                if (error.code !== 'ECONNRESET') {
+                    console.error(`Stratum V2 socket error: ${error.message}`);
+                }
+                closeSocket();
+            });
+            socket.on('close', () => {
+                if (client != null) {
+                    void client.destroy();
+                }
+            });
+        });
+
+        server.on('error', (error) => {
+            console.error(`Stratum V2 server error on port ${port}: ${error.message}`);
+        });
+
+        server.listen(port, () => {
+            console.log(`Stratum V2 server is listening on port ${port}`);
+        });
+        this.servers.push(server);
+    }
+
+    private getSocketTimeoutMs(): number {
+        const configured = parseInt(this.configService.get<string>('STRATUM_V2_SOCKET_TIMEOUT_MS') ?? '', 10);
+        return Number.isFinite(configured) && configured > 0 ? configured : 1000 * 60 * 15;
+    }
+}

src/services/telegram.service.ts

@@ -1,8 +1,8 @@
 import { Injectable, OnModuleInit } from '@nestjs/common';
 import { ConfigService } from '@nestjs/config';
+import axios, { AxiosInstance } from 'axios';
 import { validate } from 'bitcoin-address-validation';
 import { Block } from 'bitcoinjs-lib';
-import * as TelegramBot from 'node-telegram-bot-api';
 
 import { TelegramSubscriptionsService } from '../ORM/telegram-subscriptions/telegram-subscriptions.service';
 
@@ -10,7 +10,9 @@ import { TelegramSubscriptionsService } from '../ORM/telegram-subscriptions/tele
 @Injectable()
 export class TelegramService implements OnModuleInit {
 
-    private bot: TelegramBot;
+    private bot: AxiosInstance;
+    private updateOffset = 0;
+    private pollingTimer: NodeJS.Timeout;
 
     constructor(
         private readonly configService: ConfigService,
@@ -20,7 +22,10 @@ export class TelegramService implements OnModuleInit {
         if (token == null || token.length < 1) {
             return;
         }
-        this.bot = new TelegramBot(token, { polling: true });
+        this.bot = axios.create({
+            baseURL: `https://api.telegram.org/bot${token}/`,
+            timeout: 10000
+        });
         console.log('Telegram bot init');
 
 
@@ -32,23 +37,10 @@ export class TelegramService implements OnModuleInit {
             return;
         }
 
-        this.bot.onText(/\/subscribe/, async (msg) => {
-            const address = msg.text.split('/subscribe ')[1];
-            if (validate(address) == false) {
-                this.bot.sendMessage(msg.chat.id, "Invalid address.");
-                return;
-            }
-            await this.telegramSubscriptionsService.saveSubscription(msg.chat.id, address);
-            this.bot.sendMessage(msg.chat.id, "Subscribed!");
-        });
-
-        this.bot.onText(/\/start/, (msg) => {
-            this.bot.sendMessage(msg.chat.id, "Welcome to the public-pool bot. /subscribe <address> to get notified.");
-        });
-
-        this.bot.on('message', (msg) => {
-            console.log(msg);
-        });
+        await this.pollUpdates();
+        this.pollingTimer = setInterval(async () => {
+            await this.pollUpdates();
+        }, 2000);
     }
 
     public async notifySubscribersBlockFound(address: string, height: number, block: Block, message: string) {
@@ -57,8 +49,57 @@ export class TelegramService implements OnModuleInit {
         }
 
         const subscribers = await this.telegramSubscriptionsService.getSubscriptions(address);
-        subscribers.forEach(subscriber => {
-            this.bot.sendMessage(subscriber.telegramChatId, `Block Found! Result: ${message}, Height: ${height}`);
+        await Promise.all(subscribers.map(subscriber => {
+            return this.sendMessage(subscriber.telegramChatId, `Block Found! Result: ${message}, Height: ${height}`);
+        }));
+    }
+
+    private async pollUpdates() {
+        try {
+            const response = await this.bot.get('getUpdates', {
+                params: {
+                    offset: this.updateOffset,
+                    timeout: 0
+                }
+            });
+
+            for (const update of response.data.result ?? []) {
+                this.updateOffset = update.update_id + 1;
+                await this.handleMessage(update.message);
+            }
+        } catch (e) {
+            console.error('Telegram polling failed', e.message);
+        }
+    }
+
+    private async handleMessage(msg: any) {
+        if (msg?.text == null) {
+            return;
+        }
+
+        if (msg.text.startsWith('/subscribe')) {
+            const address = msg.text.split('/subscribe ')[1];
+            if (validate(address) == false) {
+                await this.sendMessage(msg.chat.id, 'Invalid address.');
+                return;
+            }
+            await this.telegramSubscriptionsService.saveSubscription(msg.chat.id, address);
+            await this.sendMessage(msg.chat.id, 'Subscribed!');
+            return;
+        }
+
+        if (msg.text.startsWith('/start')) {
+            await this.sendMessage(msg.chat.id, 'Welcome to the public-pool bot. /subscribe <address> to get notified.');
+            return;
+        }
+
+        console.log(msg);
+    }
+
+    private async sendMessage(chatId: number | string, text: string) {
+        await this.bot.post('sendMessage', {
+            chat_id: chatId,
+            text
         });
     }
-}
+}

src/utils/coinbase-prefix.utils.ts

@@ -0,0 +1,19 @@
+import { TOTAL_EXTRANONCE_SIZE_BYTES } from '../models/stratum.constants';
+
+export function patchCoinbasePrefixVarint(prefix: Buffer, totalExtranonceSize: number): Buffer {
+    if (totalExtranonceSize === TOTAL_EXTRANONCE_SIZE_BYTES) {
+        return prefix;
+    }
+    if (prefix.length < 42) {
+        return prefix;
+    }
+
+    const patched = Buffer.from(prefix);
+    const nextLength = patched[41] + (totalExtranonceSize - TOTAL_EXTRANONCE_SIZE_BYTES);
+    if (nextLength < 0 || nextLength > 0xfc) {
+        return prefix;
+    }
+
+    patched[41] = nextLength;
+    return patched;
+}

src/utils/difficulty.utils.ts

@@ -0,0 +1,117 @@
+import * as bitcoinjs from 'bitcoinjs-lib';
+
+const TRUE_DIFF_ONE_BIGINT = BigInt(
+    '26959535291011309493156476344723991336010898738574164086137773096960',
+);
+const TWO_TO_256 = 1n << 256n;
+const FRACTION_SCALE = 1_000_000_000_000_000n;
+const FRACTION_SCALE_NUM = 1e15;
+
+function bigIntRatioToDifficulty(divisor: bigint): number {
+    if (divisor === 0n) {
+        return Number.POSITIVE_INFINITY;
+    }
+
+    const scaled = (TRUE_DIFF_ONE_BIGINT * FRACTION_SCALE) / divisor;
+    return Number(scaled) / FRACTION_SCALE_NUM;
+}
+
+export class DifficultyUtils {
+    public static calculateDifficulty(header: Buffer): { submissionDifficulty: number; submissionHash: string; hashBuffer: Buffer } {
+        const hashResult = bitcoinjs.crypto.hash256(header);
+        const target = DifficultyUtils.le256ToBigInt(hashResult);
+
+        return {
+            submissionDifficulty: bigIntRatioToDifficulty(target),
+            submissionHash: hashResult.toString('hex'),
+            hashBuffer: hashResult,
+        };
+    }
+
+    public static meetsTarget(hashBuffer: Buffer, target: Buffer): boolean {
+        return DifficultyUtils.le256ToBigInt(hashBuffer) <= DifficultyUtils.le256ToBigInt(target);
+    }
+
+    public static difficultyToTarget(difficulty: number): Buffer {
+        if (!Number.isFinite(difficulty) || difficulty <= 0) {
+            return Buffer.alloc(32, 0xff);
+        }
+
+        const scale = 1_000_000n;
+        const diffScaled = BigInt(Math.round(difficulty * Number(scale)));
+        if (diffScaled === 0n) {
+            return Buffer.alloc(32, 0xff);
+        }
+
+        return DifficultyUtils.bigIntToLe256((TRUE_DIFF_ONE_BIGINT * scale) / diffScaled);
+    }
+
+    public static targetToDifficulty(target: Buffer): number {
+        if (target.length !== 32) {
+            throw new Error('Target must be 32 bytes');
+        }
+
+        const targetBigInt = DifficultyUtils.le256ToBigInt(target);
+        return bigIntRatioToDifficulty(targetBigInt);
+    }
+
+    public static hashRateToDifficulty(hashRate: number, sharesPerMinute: number): number {
+        const target = DifficultyUtils.hashRateToTarget(hashRate, sharesPerMinute);
+        return DifficultyUtils.targetToDifficulty(target);
+    }
+
+    public static clampDifficultyToMaxTarget(difficulty: number, maxTarget: Buffer): number {
+        if (maxTarget.length !== 32) {
+            return difficulty;
+        }
+
+        const maxTargetBigInt = DifficultyUtils.le256ToBigInt(maxTarget);
+        if (maxTargetBigInt === 0n) {
+            return difficulty;
+        }
+
+        const computedTargetBigInt = DifficultyUtils.le256ToBigInt(
+            DifficultyUtils.difficultyToTarget(difficulty),
+        );
+        if (computedTargetBigInt > maxTargetBigInt) {
+            const clamped = DifficultyUtils.targetToDifficulty(maxTarget);
+            return Number.isFinite(clamped) && clamped > 0 ? clamped : difficulty;
+        }
+
+        return difficulty;
+    }
+
+    private static hashRateToTarget(hashRate: number, sharesPerMinute: number): Buffer {
+        if (
+            !Number.isFinite(hashRate)
+            || hashRate <= 0
+            || !Number.isFinite(sharesPerMinute)
+            || sharesPerMinute <= 0
+        ) {
+            return Buffer.alloc(32, 0xff);
+        }
+
+        const secondsPerShare = 60 / sharesPerMinute;
+        const hashesPerShare = BigInt(Math.round(hashRate * secondsPerShare));
+        if (hashesPerShare === 0n) {
+            return Buffer.alloc(32, 0xff);
+        }
+
+        const target = (TWO_TO_256 - hashesPerShare) / (hashesPerShare + 1n);
+        return DifficultyUtils.bigIntToLe256(target);
+    }
+
+    private static bigIntToLe256(value: bigint): Buffer {
+        const buf = Buffer.alloc(32);
+        let remaining = value;
+        for (let i = 0; i < 32; i++) {
+            buf[i] = Number(remaining & 0xffn);
+            remaining >>= 8n;
+        }
+        return buf;
+    }
+
+    private static le256ToBigInt(target: Buffer): bigint {
+        return target.reduceRight((acc, byte) => (acc << 8n) | BigInt(byte), 0n);
+    }
+}

test/models/MockRecording1.ts

@@ -7,6 +7,6 @@ export class MockRecording1 {
     public static MINING_AUTHORIZE = `{"id": 3, "method": "mining.authorize", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "x"]}`;
     public static MINING_SUGGEST_DIFFICULTY = `{"id": 4, "method": "mining.suggest_difficulty", "params": [512]}`;
     public static BLOCK_TEMPLATE: IBlockTemplate = { "capabilities": ["proposal"], "version": 536870912, "rules": ["csv", "!segwit", "taproot"], "vbavailable": {}, "vbrequired": 0, "previousblockhash": "00000000000000022246451e9af7ac4f8bff2527d223f6e623740e92171592f2", "transactions": [{ "data": "02000000000101c3efa41c94ee24dd6c6aaccab0f27e9d2baf92e5112bff15cc463b600e4e3a3c0100000000fdffffff024ea319000000000017a914a5b8d32a6388f02204a1445bd623150ee3b851d18765d67b000000000017a914a316e3a4eaeee9cbee9c254c3292830281a8c9c38702473044022065fbcd2918e8b52c3af8c4ae21b3646d7a12f66ddcaa73a68273f5806527c0da0220291f555dd120bb9eadb144ccf4203db659b78d79bffcd37a29016da068f3abb9012102baab4d464b57771f5108f40ffc31b7242c5b430a61d4bfead024d715c441f3f3c7432500", "txid": "a174b99a87c899e66854ba6f101799ac852ef588ec69299846875e9d64355317", "hash": "748f4db5e45dab6a9903f50e7e760470ce80ac219c637d61418667a0ccb6c536", "depends": [], "fee": 14300, "sigops": 1, "weight": 569 }, { "data": "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", "txid": "c34ac3f822a0b49f298be1a25fc9e9dd375c23985ed2656f7cf7d87b67fee1c0", "hash": "c34ac3f822a0b49f298be1a25fc9e9dd375c23985ed2656f7cf7d87b67fee1c0", "depends": [], "fee": 9153, "sigops": 12, "weight": 1408 }, { "data": "020000000001013f8e5ebf5620f2c62c9c4e4f77bb4eb903699620da372ad44f666a552e5b9fc801000000171600148442ee1fe3742153a6b40623d363a22ceed677c3ffffffff02bc0200000000000017a91470b93cf7ead31ef24b71159388c2e8e147f755b987aa0415000000000017a9145506e665bcf63e1225100d7c8613a640699fd5d087024730440220215cd74141ebcde3aee383f232dfd2c6b011645012f35714781d28d4a6959829022017ea40a15f4116bbf0a6f86dc0af08758d9a74673498a61164ed13e9d1c712e501210294184e8093958861740c4ce32e724a24b7df7eeb04702cae274652e86b01f83a00000000", "txid": "5aaf2fa707da25c24374b87d89c420c9e4c51022a4bbed4cc91614831f359366", "hash": "2c19268e65cc223c5fac9666883ecc1d10e680c54a4fdbbb3e4775f886b0feec", "depends": [], "fee": 491, "sigops": 1, "weight": 661 }, { "data": "020000000001012c53f5b0a12cadb57602466e703e60272183b75f3366073f4841dac8e616f2740000000000feffffff02e80300000000000016001496e381bd3fe4bae631adc5a5a420fb9124e5480af0a8100000000000160014cd06fc96fea44c6c5e074ba16dd20b222a0a9b32024730440220440ba2252ea6f70f1b8106897984330a997ef504f7f0dbb89679e44309026f2b02207074ad7dbd9a2bd37a41352527b7f3e68612956fe2085a0eb0b41f97f6a3599d012103b3ecf0f44126019a94a818245e35ecff1582c2900a38487a306fcd91bdb28003c8432500", "txid": "69770cf296b64329e784a5666fb0eab034fbb1780bf067f4e1606874c214f01d", "hash": "fadcaa8de64274e63c093592ed6d8c6b7584bb92c0e8d9c49f02a4df11f6f69d", "depends": [], "fee": 141, "sigops": 1, "weight": 561 }, { "data": "01000000019e03cd78895f6876932501b66eab1e44611d48b4c5029d250b7d2d6073b44b68000000006b48304502210088dfbeb842d54893987e5afb87b70fe70e7b91ebad740782515c44464b19a74202205a6bc47ad6c925f85aa29b2be1a174efcc30a4ad8ed6cfe6236b66d7a4f8d96f01210259530ee281106e237ac3aa801d1f7699ada05501186401da78b7d88849bbda8bffffffff0204ce3900000000001976a91419803f0d83a1b58348a4617c743638bbf9ec235588ac44ce5c01000000001976a9149e38aebe02be7cecacdb521f514cffe445c5533788ac00000000", "txid": "2137ca428d6233e680cea25c428b984391314d872a1a0f5f7b8dc8cfc4474c44", "hash": "2137ca428d6233e680cea25c428b984391314d872a1a0f5f7b8dc8cfc4474c44", "depends": [], "fee": 226, "sigops": 8, "weight": 904 }], "coinbaseaux": {}, "coinbasevalue": 2465717, "longpollid": "00000000000000022246451e9af7ac4f8bff2527d223f6e623740e92171592f29370", "target": "000000000000002495f800000000000000000000000000000000000000000000", "mintime": 1689512405, "mutable": ["time", "transactions", "prevblock"], "noncerange": "00000000ffffffff", "sigoplimit": 80000, "sizelimit": 4000000, "weightlimit": 4000000, "curtime": 1689514989, "bits": "192495f8", "height": 2442185, "default_witness_commitment": "6a24aa21a9edbd3d1d916aa0b57326a2d88ebe1b68a1d7c48585f26d8335fe6a94b62755f64c" };
-    public static MINING_SUBMIT = `{"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "c7080000", "64b3f3ec", "ed460d91", "00002000"]}`;
+    public static MINING_SUBMIT = `{"id": 5, "method": "mining.submit", "params": ["tb1qumezefzdeqqwn5zfvgdrhxjzc5ylr39uhuxcz4.bitaxe3", "1", "c708000000000000", "64b3f3ec", "ed460d91", "00002000"]}`;
     public static TIME = '64b3f3ec';
-}
+}