Programmatic Usage

Bunup can be used programmatically in your scripts. This is useful when you need custom build workflows or want to integrate bunup into your own tools.

INFO

The build function must be run in the Bun runtime.

Basic Usage

import { build } from 'bunup';

const result = await build({
  entry: 'src/index.ts',
});

console.log('Built files:', result.files);
console.log('Build context:', result.build);

Build Result

The build function returns a BuildResult object containing information about the generated files and build context:

type BuildResult = {
  /** Array of generated files with their paths and metadata */
  files: BuildOutputFile[]
  /** Build configuration and metadata that were used */
  build: {
    /** Build configuration options that were used */
    options: BuildOptions
    /** Build execution metadata */
    meta: BuildMeta
  }
}

type BuildOutputFile = {
  /** The entry point for which this file was generated (undefined for chunks/assets) */
  entrypoint: string | undefined
  /** The kind of the file */
  kind: 'entry-point' | 'chunk' | 'asset' | 'sourcemap' | 'bytecode'
  /** Absolute path to the generated file */
  fullPath: string
  /** Path relative to the root directory */
  pathRelativeToRootDir: string
  /** Path relative to the output directory */
  pathRelativeToOutdir: string
  /** Whether the file is a TypeScript declaration file */
  dts: boolean
  /** The format of the output file */
  format: Format
  /** The size of the file in bytes */
  size: number
}

Options

The build function accepts the same options as defineConfig. See the Options Guide for detailed documentation of all available options.

For TypeScript users, the BuildOptions type is available:

import { build, type BuildOptions } from 'bunup';

const options: BuildOptions = {
  entry: 'src/index.ts',
  format: ['esm', 'cjs'],
};

await build(options);

The full type definition can be found in the bunup source code.

Custom Root Directory

The build function accepts an optional second parameter to specify a custom root directory. By default, it uses process.cwd().

import { build } from 'bunup';

await build({
  entry: 'src/index.ts',
}, '/path/to/your/project');

await build({
  entry: 'src/index.ts',
}, './my-project');

Using Plugins

Plugins can be used programmatically the same way they are used in the configuration file:

import { build } from 'bunup';
import { copy } from 'bunup/plugins';
import { tailwindcss } from '@bunup/plugin-tailwindcss';

await build({
  entry: 'src/index.ts',
  plugins: [
    tailwindcss({
      minify: true,
    }),
    copy(['README.md', 'assets/**/*']),
  ]
});