Desktop · Windows & Linux
A Monaco-powered playground for Node.js — multi-tab, npm-sandboxed, and inspired by the TypeScript Playground. No project folder, no install step, no ceremony.
Features
Built for the moment you want to test one thing, not scaffold an app.
The same engine behind VS Code — full syntax highlighting, IntelliSense, and auto-formatting.
Open as many tabs as you need. Each keeps its own editor and console output, renamed with a double-click.
Write await fetch(...) directly — no wrapping everything in an async function first.
Install any package — axios, lodash, dayjs — from the UI. Installed once, isolated, persisted between sessions.
A dark terminal panel shows stdout and stderr after every run, with errors highlighted in red.
Every tab and its content is saved automatically and restored the next time you launch.
How it works
Your code is automatically wrapped in an async IIFE, so top-level await always works.
It's written to a temporary .js file inside the NPM sandbox folder.
Run as a Node child process from within the sandbox, so any require(...) resolves against its own node_modules.
The temporary file is deleted immediately after execution. Isolated, fast, and it never touches your global Node environment.
Tech stack