// Built-in TypeScript
import { serve } from "bun"

serve({
  port: 3000,
  fetch(req) {
    return new Response("Hello from Bun!")
  }
})

// Built-in test runner
import { test, expect } from "bun:test"

test("math", () => {
  expect(2 + 2).toBe(4)
})

// Built-in bundler
await Bun.build({
  entrypoints: ["./index.ts"],
  outdir: "./dist",
})

// Secure by default
// deno run --allow-net server.ts

Deno.serve({ port: 3000 }, (req) => {
  return new Response("Hello from Deno!")
})

// Built-in formatter and linter
// deno fmt
// deno lint

// Native TypeScript
const data: string = await Deno.readTextFile("./file.txt")

// The standard
import { createServer } from 'http'

createServer((req, res) => {
  res.end('Hello from Node!')
}).listen(3000)

// Massive ecosystem
// 2.5M+ packages on npm
// Works with everything

// First-class Web APIs
const response = await fetch("https://api.example.com")
const data = await response.json()

// Web Streams
const file = await Deno.open("./large.txt")
const readable = file.readable

// Also Web-first
const server = Bun.serve({
  websocket: {
    message(ws, message) {
      ws.send(message) // Echo
    }
  }
})

// Bun shines with SQLite
import { Database } from "bun:sqlite"

const db = new Database("app.db")
const query = db.query("SELECT * FROM users WHERE id = ?")

// 5x faster than Node
for (let i = 0; i < 10000; i++) {
  query.get(i)
}

# Run TypeScript directly
bun run script.ts

# Install deps crazy fast
bun install # <1s vs 15s

// Explicit permissions
// deno run --allow-read=./data --allow-net=api.example.com app.ts

// Can't access outside permissions

// Built for Web APIs
const kv = await Deno.openKv()
await kv.set(["users", userId], userData)

// Deploy to edge easily
Deno.serve(handler) // Works on Deno Deploy

// package.json
{
  "scripts": {
    - "start": "node index.js",
    + "start": "bun index.js",
    - "test": "jest",
    + "test": "bun test"
  }
}

// More work required
// Old (Node)
const fs = require('fs').promises
const data = await fs.readFile('./file.txt', 'utf8')

// New (Deno)
const data = await Deno.readTextFile('./file.txt')

Need maximum speed? → Bun
Need security/modern? → Deno  
Need compatibility? → Node.js
Need stability? → Node.js
Building new? → Try Bun/Deno
Have legacy? → Stick with Node