rollup-plugin-tree-shakeable

2.0.0 verified Mon Apr 27 auth: no javascript

A Rollup plugin (v2.0.0, latest) that automatically adds @__PURE__ annotations to top-level expressions in your JavaScript/TypeScript modules, convincing bundlers like Rollup, esbuild, and webpack that the module is side-effect free and enabling effective tree-shaking. Unlike setting `sideEffects: false` in package.json, which cannot handle function calls at module scope, this plugin annotates each call individually. Requires Node >= 22 and Rollup. Lightweight, zero-config, and actively maintained with few dependencies.

Common errors

error Require is not defined in ES module scope ↓

cause Package uses ESM; require() is not supported without special configuration.

fix

Use import syntax or set "type": "module" in package.json and consume as ES module.

error Cannot find module 'rollup-plugin-tree-shakeable' ↓

cause Plugin not installed or path incorrect.

fix

Run npm install rollup-plugin-tree-shakeable --save-dev and ensure import path is correct.

error TypeError: treeShakeable is not a plugin function ↓

cause treeShakeable() returns a plugin object, but treeShakeable alone is the function, not a plugin.

fix

Call treeShakeable() in the plugins array: plugins: [treeShakeable()]

Warnings

breaking Only use if your package is actually tree-shakeable: each export works independently when others are stripped. ↓

fix Verify that your module does not have side-effectful top-level expressions that depend on other exports.

gotcha Does NOT handle all cases: side effects inside exported function bodies are not annotated. ↓

fix Manually add @__PURE__ or refactor code that produces side effects inside functions.

breaking v2.0.0 requires Node >= 22; older versions of Node are unsupported. ↓

fix Upgrade to Node 22 or stay on v1.0.3.

deprecated v1.x may not be receiving further updates; upgrade to v2 for ongoing maintenance. ↓

fix Update to latest: npm install rollup-plugin-tree-shakeable@latest

Install

npm install rollup-plugin-tree-shakeable

yarn add rollup-plugin-tree-shakeable

pnpm add rollup-plugin-tree-shakeable

Imports

default
wrong
```
const treeShakeable = require('rollup-plugin-tree-shakeable')
```
correct
```
import treeShakeable from 'rollup-plugin-tree-shakeable'
```
Plugin has a default export; CommonJS require() may not work if the package is ESM-only (check your Rollup config). v2.0.0 likely ESM-only.
Plugin
wrong
```
import { Plugin } from 'rollup-plugin-tree-shakeable'
```
correct
```
import type { Plugin } from 'rollup'
```
The plugin does not export a Plugin type; you need to import it from Rollup itself.

application

wrong

export default { plugins: [treeShakeable] }

correct

import treeShakeable from 'rollup-plugin-tree-shakeable'; export default { plugins: [treeShakeable()] }

treeShakeable is a function that must be called; omitting parentheses will not produce a plugin instance.

Quickstart

Shows basic Rollup config using treeShakeable and demonstrates how top-level function calls get annotated with @__PURE__.

// install: npm i rollup rollup-plugin-tree-shakeable
import treeShakeable from 'rollup-plugin-tree-shakeable';

export default {
  input: 'src/index.js',
  output: {
    dir: 'output',
    format: 'esm',
  },
  plugins: [treeShakeable()],
};

// src/index.js (before plugin)
const withLogging = fn => (...args) => {
  console.log('start');
  try { return fn(...args); } finally { console.log('end'); }
};
export const f1 = withLogging(() => 1);
export const f2 = withLogging(() => 2);

// After plugin: each top-level call gets @__PURE__
// export const f1 = /* @__PURE__*/ withLogging(() => 1);
// export const f2 = /* @__PURE__*/ withLogging(() => 2);