ezBun

Make running Bun sandboxes easy. ezbun is a CLI tool that scans your project for scripts and provides an interactive menu to run them. It also includes built-in environment variable validation and type generation.

Without direct installation with bunx:

bunx ezbun

Installed into your project:

bun ezbun

Tip. you can add a script to your package.json:

{
  "scripts": {
    "dev": "ezbun --watch", // with hot reloading
    "start": "ezbun"
  }
}

Then run:

bun dev

CLI Options

Customize behavior with command-line flags:

# Default usage - scans ./src for ts, tsx, js, jsx, cjs, mjs files
ezbun

# Custom directory
ezbun --dir ./scripts

# Custom file extensions
ezbun --extensions js,ts

# Combined options
ezbun --dir ./src --extensions ts,tsx,js

# Watch mode (hot reloading)
ezbun --watch

# Short flags
ezbun -d ./scripts -e js,ts --watch

Available options:

• --dir, -d - Source directory (default: ./src)
• --extensions, -e - Comma-separated extensions (default: ts,tsx,js,jsx,cjs,mjs)
• --watch - Run in watch mode

Watch Mode

You can run scripts in watch mode (hot reloading) by passing the --watch flag:

bun ezbun --watch

1. Create an env.schema.ts file in your project root:

import { defineEnv } from "ezbun";
import { z } from "zod";

export default defineEnv({
  DATABASE_URL: z.url().startsWith("postgres://"),
  API_KEY: z.string().startsWith("sk-"),
  PORT: z.coerce.number(),
});

2. When you run a script via ezbun, it will:

• Validate process.env against your schema.
• Print helpful error messages if validation fails.
• Automatically generate env.d.ts for global type definitions.

Now you can use process.env with full type safety in your code!

/** typed as `string` not `string | undefined` */
console.log(process.env.API_KEY);