Bun 1.2+ Runtime Expert (2026 High-Performance Standard)

English | Bahasa Indonesia

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English

Orchestration & Integration

Connects and orchestrates with domain skills:

• Backend & APIs: js-backend-expert (Hono on Bun, Fastify/Express migration), api-design-expert (REST & WebSocket contracts), and sse-websocket-streaming-expert (native Bun.serve WebSockets).
• Database & Storage: database-orm-expert (Drizzle ORM with native bun:sql, PostgreSQL/SQLite) and file-upload-media-expert (zero-dependency Bun.s3 client).
• Quality & Testing: autonomous-tdd-debugger, e2e-testing-expert, and anti-slop for executing high-speed bun test suites with snapshot matching.
• Orchestration: brainstorming and zero-to-prod-orchestrator (Phase 4: Backend & APIs).

Description

Expert-level guidance for engineering ultra-low-latency backend microservices with Bun 1.2+. Covers the native PostgreSQL driver (import { SQL } from 'bun'), native S3 object storage (Bun.s3), git-friendly text lockfiles (bun.lock), multi-core HTTP clustering via reusePort, built-in SQLite, and high-speed Jest-compatible unit testing via bun:test.

Trigger Conditions

• Scaffolding new high-performance microservices, REST APIs, or WebSocket hubs using Bun.
• Querying PostgreSQL or SQLite without external drivers using native Bun.sql.
• Interacting with Amazon S3, Cloudflare R2, or MinIO using zero-dependency Bun.s3.
• Running multi-core HTTP services with automatic load distribution across CPU cores.
• Executing unit and integration tests using bun test.
• Migrating legacy Node.js/npm codebases to Bun's native execution layer.

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Bun 1.2+ Core Architectural Features

1. Native PostgreSQL Client (import { SQL } from 'bun')

Bun 1.2 includes a built-in, high-speed PostgreSQL driver that communicates directly via binary wire protocol without pg or postgres.js:

// src/lib/db.ts
import { SQL } from 'bun';

// Instantiate pooled database client
export const sql = new SQL({
  url: process.env.DATABASE_URL || 'postgres://user:password@localhost:5432/production_db',
  max: 20, // Connection pool size
  idleTimeout: 30, // Max idle time in seconds
});

export interface UserAccount {
  id: string;
  email: string;
  balance: number;
}

// 1. Tagged template query with automatic parameterized SQL injection defense
export async function getActiveUser(email: string): Promise<UserAccount | null> {
  const users = await sql<UserAccount[]>`
    SELECT id, email, balance 
    FROM users 
    WHERE email = ${email} AND active = true 
    LIMIT 1
  `;
  return users[0] ?? null;
}

// 2. Atomic Database Transaction
export async function transferFunds(fromUserId: string, toUserId: string, amount: number) {
  return await sql.begin(async (tx) => {
    const debit = await tx`
      UPDATE users 
      SET balance = balance - ${amount} 
      WHERE id = ${fromUserId} AND balance >= ${amount} 
      RETURNING id, balance
    `;

    if (debit.length === 0) {
      throw new Error('Insufficient funds or sender not found');
    }

    await tx`
      UPDATE users 
      SET balance = balance + ${amount} 
      WHERE id = ${toUserId}
    `;

    return { success: true };
  });
}

2. Native Object Storage (Bun.s3)

Interact with AWS S3, Cloudflare R2, or MinIO with zero external SDK dependencies:

// src/lib/storage.ts
import { s3 } from 'bun';

// Configure credentials once or let Bun auto-detect AWS_* environment variables
s3.credentials({
  accessKeyId: process.env.S3_ACCESS_KEY_ID!,
  secretAccessKey: process.env.S3_SECRET_ACCESS_KEY!,
  bucket: process.env.S3_BUCKET_NAME!,
  region: process.env.S3_REGION || 'auto',
  endpoint: process.env.S3_ENDPOINT, // e.g. https://<account_id>.r2.cloudflarestorage.com
});

// Upload file directly from memory buffer
export async function uploadInvoicePdf(invoiceId: string, pdfBuffer: Buffer): Promise<string> {
  const fileKey = `invoices/${invoiceId}.pdf`;
  await s3.write(fileKey, pdfBuffer, {
    type: 'application/pdf',
  });
  return fileKey;
}

// Generate presigned upload URL for direct browser uploads
export function getDirectUploadUrl(fileName: string): string {
  return s3.presign(`uploads/${fileName}`, {
    method: 'PUT',
    expiresIn: 300, // 5 minutes
  });
}

3. Multi-Core HTTP Clustering with Bun.serve()

Scale HTTP throughput across all CPU cores on a single host with reusePort: true:

// src/server.ts
import { serve } from 'bun';

const server = serve({
  port: Number(process.env.PORT) || 3000,
  reusePort: true, // Enables SO_REUSEPORT: spawn multiple instances to scale across cores
  async fetch(req) {
    const url = new URL(req.url);

    if (url.pathname === '/health') {
      return Response.json({
        status: 'healthy',
        pid: process.pid,
        timestamp: new Date().toISOString(),
      });
    }

    return new Response('Not Found', { status: 404 });
  },
  error(error) {
    return new Response(`Internal Server Error: ${error.message}`, { status: 500 });
  },
});

console.log(`Worker process ${process.pid} listening on port ${server.port}`);

4. Human-Readable Text Lockfile (bun.lock)

In Bun 1.2+, the default lockfile format is a plain text bun.lock file (replacing binary bun.lockb):

• Git-Friendly: Clean line-by-line diffs in Pull Requests.
• Merge-Conflict Resilient: Standard git conflict resolution tools work seamlessly.
• Auditable: Dependencies and integrity hashes can be inspected with standard CLI tools (cat, grep).

5. Fast Testing with bun:test

Jest/Vitest compatible test suite running natively on JavaScriptCore:

// test/user.test.ts
import { describe, expect, it, beforeEach } from 'bun:test';
import { getActiveUser, sql } from '../src/lib/db';

describe('User Database Service', () => {
  beforeEach(async () => {
    await sql`TRUNCATE TABLE users CASCADE`;
    await sql`INSERT INTO users (id, email, balance, active) VALUES ('usr-1', 'test@example.com', 100.0, true)`;
  });

  it('retrieves active user by email', async () => {
    const user = await getActiveUser('test@example.com');
    expect(user).not.toBeNull();
    expect(user?.email).toBe('test@example.com');
    expect(user?.balance).toBe(100.0);
  });

  it('returns null for inactive or missing user', async () => {
    const missing = await getActiveUser('missing@example.com');
    expect(missing).toBeNull();
  });
});

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Bahasa Indonesia

Integrasi Orkestrasi

Terhubung dan mengorkestrasi bersama skill domain:

• Backend & API: js-backend-expert (Hono di atas Bun, migrasi Fastify/Express), api-design-expert (kontrak REST & WebSocket), dan sse-websocket-streaming-expert (WebSocket native Bun.serve).
• Database & Penyimpanan: database-orm-expert (Drizzle ORM dengan native bun:sql, PostgreSQL/SQLite) dan file-upload-media-expert (klien object storage Bun.s3 zero-dependency).
• Kualitas & Pengujian: autonomous-tdd-debugger, e2e-testing-expert, dan anti-slop untuk eksekusi test runner bun test berkecepatan tinggi dengan pencocokan snapshot.
• Orkestrator Utama: brainstorming dan zero-to-prod-orchestrator (Fase 4: Backend & APIs).

Deskripsi

Panduan tingkat ahli untuk rekayasa microservices backend berlatensi ultra-rendah menggunakan Bun 1.2+. Mencakup driver PostgreSQL native (import { SQL } from 'bun'), penyimpanan objek native S3 (Bun.s3), format lockfile teks yang ramah git (bun.lock), clustering HTTP multi-core melalui reusePort, SQLite bawaan, dan pengujian unit kompatibel Jest via bun:test.

Kondisi Pemicu

• Merancang microservices baru, REST API, atau hub WebSocket berkecepatan tinggi dengan Bun.
• Melakukan query database PostgreSQL atau SQLite tanpa library eksternal menggunakan Bun.sql.
• Berinteraksi dengan AWS S3, Cloudflare R2, atau MinIO tanpa dependensi AWS SDK via Bun.s3.
• Menjalankan layanan HTTP multi-core dengan pembagian beban otomatis di semua core CPU.
• Menjalankan pengujian unit dan integrasi berkecepatan tinggi menggunakan bun test.

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Fitur Arsitektur Inti Bun 1.2+

1. Klien PostgreSQL Native (import { SQL } from 'bun')

Bun 1.2 menyertakan driver PostgreSQL berkecepatan tinggi yang berkomunikasi langsung melalui protokol biner tanpa overhead library pihak ketiga:

import { SQL } from 'bun';

export const sql = new SQL({
  url: process.env.DATABASE_URL || 'postgres://user:password@localhost:5432/db_produksi',
  max: 20,
});

// Query aman terhadap SQL Injection melalui tagged template literals
export async function cariPenggunaAktif(email: string) {
  const pengguna = await sql`
    SELECT id, email, balance 
    FROM users 
    WHERE email = ${email} AND active = true 
    LIMIT 1
  `;
  return pengguna[0] ?? null;
}

2. Klien Object Storage Native (Bun.s3)

Unggah dan kelola file di S3 atau Cloudflare R2 secara native:

import { s3 } from 'bun';

// Unggah buffer file dokumen langsung
export async function simpanFaktur(fakturId: string, pdfBuffer: Buffer) {
  const namaFile = `faktur/${fakturId}.pdf`;
  await s3.write(namaFile, pdfBuffer, { type: 'application/pdf' });
  return namaFile;
}

// Buat URL presigned untuk upload langsung dari browser klien
export function buatUrlUploadLangsung(namaFile: string) {
  return s3.presign(`unggah/${namaFile}`, {
    method: 'PUT',
    expiresIn: 300,
  });
}

3. Clustering HTTP Multi-Core dengan Bun.serve()

import { serve } from 'bun';

const server = serve({
  port: Number(process.env.PORT) || 3000,
  reusePort: true, // Memungkinkan beberapa proses Bun berjalan di port yang sama lintas CPU cores
  async fetch(req) {
    return Response.json({
      status: 'aktif',
      pid: process.pid,
      waktu: new Date().toISOString(),
    });
  },
});