Kyushu – A self-hostable WASM sandbox for JavaScript workers

In plain words

Kyushu is a self-hostable WebAssembly sandbox designed to run JavaScript workers in isolated environments. It allows developers to execute JavaScript code safely within a contained WASM runtime that can be hosted on their own infrastructure. The product is aimed at developers who need secure code execution capabilities without relying on third-party services. The self-hosting option distinguishes it from cloud-based alternatives, giving users full control over their runtime environment.

written from the facts on this page · September 2026

From the sources

Kyushu is a self-hostable Wasm sandbox for JavaScript workers. Think Cloudflare Workers, but on your own VPS. Write a JS fetch handler, ship it as a standalone binary, and run it on your server. Use cases could be running untrusted code safely, building edge-like handlers on your infra, or giving AI agents a sandboxed environment to execute logic. Open source. Early stage. Give it a try and upvote if you ❤️ it!

Ever wanted to run a Cloudflare Workers-style handler, on a VPS or anywhere, without Node.js, Bun, or even Docker? curl -fsSL https://kyushu.dev/install | bash Get started View on GitHub What is Kyushu? Kyushu is an open source CLI that lets you write a JavaScript or TypeScript handler, build it into a self-contained WebAssembly binary, and run it anywhere with one command - kyufrom kyushu.dev

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