bunjs-env

Cross-platform environment variable setter optimized for Bun.js.

Installation

# Install globally
bun install -g bunjs-env

# Or use with bunx (no installation required)
bunx bunjs-env NODE_ENV=production bun run start

Usage

Set environment variables before running commands, works consistently across all platforms:

bunjs-env NODE_ENV=production bun run start
bunjs-env DEBUG=true API_KEY=secret bun run dev
bunjs-env NODE_ENV=test bun test

Multiple Environment Variables

bunjs-env NODE_ENV=production PORT=3000 DEBUG=false bun run start

Debug Mode

See exactly what environment variables are set and which command is executed:

bunjs-env --debug NODE_ENV=test bun run test

Why bunjs-env?

Built specifically for the Bun ecosystem with native performance optimizations. Inspired by the excellent cross-env but optimized for Bun's unique capabilities:

• Zero dependencies - Lightweight and secure
• Native Bun integration - Uses Bun's built-in shell capabilities
• TypeScript ready - Works seamlessly with TypeScript projects
• Fast execution - Leverages Bun's performance advantages

Note: If you're using Node.js, cross-env is the excellent standard choice. bunjs-env is designed specifically for Bun users who want native integration.

Examples

Development

bunjs-env NODE_ENV=development DEBUG=true bun run dev
bunjs-env NODE_ENV=test DATABASE_URL=test.db bun test

Production

bunjs-env NODE_ENV=production bun run build
bunjs-env NODE_ENV=production PORT=8080 bun run start

CI/CD

bunjs-env NODE_ENV=test CI=true bun run test:coverage

CLI Options

• -h, --help — Show help message
• --debug — Enable debug output showing environment variables and command execution

Requirements

• Bun.js >= 1.0.0

API

Environment variables must follow standard naming conventions:

• Start with a letter or underscore
• Contain only letters, numbers, and underscores
• Format: KEY=value

Migration from cross-env

Switching from cross-env is straightforward - just replace cross-env with bunjs-env:

# Before (cross-env)
cross-env NODE_ENV=production npm run build

# After (bunjs-env)
bunjs-env NODE_ENV=production bun run build

License

MIT License — see LICENSE for details.

Related

• cross-env
• Bun.js