Bun

# Installing packages
bun install
 
# Adding dependencies
bun add express
 
# Running scripts
bun run start

// bunfig.toml
[bundle]
entrypoints = ["./src/index.ts"]
outdir = "./dist"
 
// Command line bundling
bun build ./src/index.ts --outdir ./dist

// Start development server with hot reloading
bun --hot run dev.ts

// TypeScript works out of the box
interface Config {
  port: number;
  env: string;
}
 
const config: Config = {
  port: 3000,
  env: 'development'
};

import { expect, test, describe } from "bun:test";
 
describe("math operations", () => {
  test("addition", () => {
    expect(2 + 2).toBe(4);
  });
 
  test("async operation", async () => {
    const result = await Promise.resolve(42);
    expect(result).toBe(42);
  });
});

const server = Bun.serve({
  port: 3000,
  async fetch(req) {
    const url = new URL(req.url);
    
    if (url.pathname === "/") {
      return new Response("Welcome to Bun!");
    }
    
    return new Response("404!", { status: 404 });
  },
});
 
console.log(`Listening on http://localhost:${server.port}`);

const server = Bun.serve({
  websocket: {
    open(ws) {
      console.log("Client connected");
    },
    message(ws, message) {
      ws.send(`Received: ${message}`);
    },
    close(ws) {
      console.log("Client disconnected");
    },
  },
  fetch(req, server) {
    if (server.upgrade(req)) {
      return;
    }
    return new Response("Upgrade failed", { status: 500 });
  },
});

const db = new Bun.SQLite(":memory:");
 
// Create table
db.run(`
  CREATE TABLE users (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    name TEXT,
    email TEXT
  )
`);
 
// Insert data
db.run(`
  INSERT INTO users (name, email)
  VALUES (?, ?)
`, ["John Doe", "john@example.com"]);
 
// Query data
const users = db.query("SELECT * FROM users").all();

// Fast file operations
const file = Bun.file("large-file.txt");
const text = await file.text();
const buffer = await file.arrayBuffer();
 
// Write files
await Bun.write("output.txt", "Hello, Bun!");

// Direct memory access
const buffer = new ArrayBuffer(1024);
const view = new DataView(buffer);
 
// Zero-copy operations
const file = Bun.file("data.bin");
const arrayBuffer = await file.arrayBuffer();

FROM oven/bun

WORKDIR /app

COPY package.json bun.lockb ./
RUN bun install --frozen-lockfile

COPY . .

ENV PORT=3000
EXPOSE 3000

CMD ["bun", "run", "start"]

const config = {
  port: parseInt(process.env.PORT || "3000"),
  nodeEnv: process.env.NODE_ENV || "development",
  apiKey: process.env.API_KEY
};

process.on("uncaughtException", (err) => {
  console.error("Uncaught Exception:", err);
  process.exit(1);
});
 
process.on("unhandledRejection", (reason, promise) => {
  console.error("Unhandled Rejection at:", promise, "reason:", reason);
});