Bunli - The CLI Framework for Bun

What is Bunli?

Bunli is a complete ecosystem for building command-line interfaces with Bun. It combines a minimal, type-safe framework with powerful tooling for development, testing, building, and distribution.

Type-Safe

Full TypeScript support with automatic type inference and code generation

// Types flow automatically
handler: async ({ flags }) => {
  // flags is fully typed
}

// Generated types for advanced patterns
import { getCommandApi } from './commands.gen'

Zero Dependencies

Pure implementation with no external dependencies

"dependencies": {}

Fast Startup

Leverages Bun's quick boot time for instant CLI response

$ time mycli --help
0.012s

Production Ready

Automated builds, releases, and cross-platform distribution

bunli build --targets all
bunli release

Quick Start

# Create a new CLI project
bunx create-bunli my-cli
cd my-cli

# Start development
bunli dev

# Build for production
bunli build

# Create a new CLI project
npx create-bunli my-cli
cd my-cli

# Start development
npm run dev

# Build for production
npm run build

Why Bunli?

Designed for Bun

Bunli is built specifically for the Bun runtime, taking advantage of:

Native TypeScript execution
Built-in test runner
Fast startup times
Bun Shell integration
Single-file executables

Type Inference First

Strong typing without manual annotations:

import { defineCommand, option } from "@bunli/core";
import { z } from "zod";

// Bunli infers everything
export default defineCommand({
  name: "deploy",
  options: {
    env: option(z.enum(["dev", "staging", "prod"]), { description: "Target environment" }),
  },
  handler: async ({ flags }) => {
    // TypeScript knows flags.env is 'dev' | 'staging' | 'prod'
    switch (flags.env) {
      case "dev": // ✅ Autocompleted
      case "staging": // ✅ Autocompleted
      case "prod": // ✅ Autocompleted
    }
  },
});

Standard Schema Support

Use any validation library you prefer:

import { defineCommand, option } from "@bunli/core";
import { z } from "zod";

export default defineCommand({
  name: "serve",
  description: "Example command",
  options: {
    email: option(z.string().email(), { description: "Email address" }),
    port: option(z.coerce.number().int().min(1).max(65535), { description: "Port" }),
  },
  handler: async ({ flags }) => {
    // flags.email is string
    // flags.port is number
  },
});