GitHub - unjs/obuild: 📦 😯 Zero-config ESM/TS package builder.

✅ Zero-config ESM/TS package builder powered by rolldown.

Used by

Usage

CLI

# bundle
npx obuild ./src/index.ts

# transform
npx obuild ./src/runtime/:./dist/runtime

You can use --dir to set the working directory.

If paths end with /, obuild uses transpile mode using oxc-transform instead of bundle mode with rolldown.

Programmatic

import { build } from "obuild";

await build({
  cwd: ".",
  entries: ["./src/index.ts"],
});

Config

You can use build.config.mjs (or .ts) or pass config to build() function.

import { defineBuildConfig } from "obuild/config";

export default defineBuildConfig({
  entries: [
    {
      type: "bundle",
      input: ["./src/index.ts", "./src/cli.ts"],
      // outDir: "./dist",
      // minify: false,
      // stub: false,
      // rolldown: {}, // https://rolldown.rs/reference/config-options
      // dts: {}, // https://github.com/sxzz/rolldown-plugin-dts#options
    },
    {
      type: "transform",
      input: "./src/runtime",
      outDir: "./dist/runtime",
      // minify: false,
      // stub: false,
      // oxc: {},
      // resolve: {}
    },
  ],
  hooks: {
    // start: (ctx) => {},
    // end: (ctx) => {},
    // entries: (entries, ctx) => {},
    // rolldownConfig: (config, ctx) => {},
    // rolldownOutput: (output, res, ctx) => {},
  },
});

Stub Mode

When working on a package locally, it can be tedious to rebuild or run the watch command every time.

You can use stub: true (per entry config) or the --stub CLI flag. In this mode, obuild skips the actual build and instead links the expected dist paths to the source files.

For bundle entries, .mjs and .d.mts files re-export the source file.
For transpile entries, src dir is symlinked to dist.

Caveats:

You need a runtime that natively supports TypeScript. Deno, Bun, Vite, and Node.js (1)
For transpile mode, you need to configure your bundler to resolve either .ts or .mjs extensions.
For bundle mode, if you add a new entry or add/remove a default export, you need to run the stub build again.

(1) For Node.js, you have several options:

Using node --experimental-strip-types (Available in 22.6)
Using jiti (node --import jiti/register)
Using oxc-node (node --import @oxc-node/core/register)
Using unloader (node --import unloader/register)

Prior Arts

unbuild: Stable solution based on rollup and mkdist.
tsdown: Alternative bundler based on rolldown.

License

💛 Released under the MIT license.