Node Plugins

Node plugins provide seamless integration with Node.js environments by handling Node-specific features and functionality automatically.

TIP

If you have suggestions or ideas for Node plugins, please open a new issue.

shims

The Shims plugin provides compatibility layers for Node.js globals and ESM/CJS interoperability. It automatically adds appropriate shims when it detects usage of environment-specific features in your code.

Usage

import { defineConfig } from 'bunup';
import { shims } from 'bunup/plugins';

export default defineConfig({
	entry: ['src/index.ts'],
	format: ['esm', 'cjs'],
	plugins: [shims()],
});

For example:

• For CJS output, any import.meta.url references are transformed to pathToFileURL(__filename).href
• For ESM output, any __dirname and __filename references are transformed to use dirname(fileURLToPath(import.meta.url))

This ensures your code works consistently across different module formats and environments without requiring manual compatibility code.