esrun

library3.2.30jsnpmunverified

esrun is a lightweight CLI tool that executes TypeScript and modern JavaScript files directly using esbuild for near-instant compilation, without requiring a bundler. It supports custom tsconfig, top-level await, and watch mode for re-executing on file changes. It handles both CJS and ESM dependencies seamlessly. However, the package is deprecated as of version 3.2.30 (current stable). Maintainers recommend migrating to Bun or, for Node.js compatibility, tsx. Last useful release: 3.2.30, minimal maintenance since. Designed for quick demonstrations and test execution, it differentiates itself by zero-config setup and esbuild's speed, but is now superseded.

devops

npm install esrun

github ↗package ↗

INSTALL

IMPORT

SIG · ESRUN

esrun

devopsjavascriptv3.2.30

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ import esrun from 'esrun'

✗ const esrun = require('esrun')

The package is ESM-only from v3; CommonJS require will throw.

run

✓ import { run } from 'esrun'

✗ const { run } = require('esrun')

Named export 'run' available only via ESM import.

types (TypeScript)

✓ import type { Options } from 'esrun'

✗ import { Options } from 'esrun' (value import)

Types are exported, but using them as values will cause runtime errors.

Shows a minimal TypeScript file with an async import, executed via esrun CLI.

// 1. Install globally or locally // npm i -g esrun // 2. Create a TypeScript file: hello.ts // content: import { run } from 'esrun'; import { greet } from './greet'; async function main() { const message = await greet('World'); console.log(message); } // greet.ts export async function greet(name: string): Promise<string> { return `Hello, ${name}!`; } // 3. Execute: esrun hello.ts

esrun --version

Debug

Known issues

deprecatedThis package is deprecated. Use Bun or tsx instead.

fix

Migrate to Bun (bun run file.ts) or tsx (npx tsx file.ts).

affects: >=3.0.0

breakingv3 dropped CommonJS support. require() will throw.

fix

Use ESM imports (import) or use an older v2.x if absolutely required.

affects: >=3.0.0

gotchaWatch mode flag --watch must be placed before the file path, otherwise it's passed as an argument to the script.

fix

Correct: esrun --watch foo.ts. Wrong: esrun foo.ts --watch.

affects: >=1.0.0

gotchaTop-level await requires module setting in tsconfig: "module": "esnext".

fix

Set "compilerOptions": { "module": "esnext" } in tsconfig.json.

affects: >=2.0.0

deprecatedUse of --tsconfig parameter may be removed in future versions.

fix

Pass tsconfig via esrun --tsconfig=/path (still supported, but not guaranteed).

affects: >=3.0.0

Errors

Common errors & fixes

Error [ERR_REQUIRE_ESM]: require() of ES Module /path/to/esrun not supported.

Using CommonJS require() with ESM-only esrun v3.

fix

Change to dynamic import: const esrun = await import('esrun'); or switch to ESM.

ReferenceError: exports is not defined in ES module scope

Mixing import/export with CommonJS module.exports in the executed file.

fix

Use consistent ESM syntax: export/import, not module.exports/require.

Could not resolve: /path/to/tsconfig.json (tsconfig not found)

Invalid path provided to --tsconfig parameter.

fix

Use absolute path or relative path from current working directory.

Upgrade

Version history

3.2.30latest on npm

Audit

Dependencies

esbuildrequiredUsed to compile TypeScript to JavaScript at runtime.

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/digital-loukoum/esrun ↗

packagehttps://www.npmjs.com/package/esrun ↗