Cloudflare recently announced worker, its new open source JavaScript/Wasm runtime that is based on the same code that powers Cloudflare Workers.
Although the worker shares most of its code with the runtime environment that Cloudfare Workers provides, it has been modified to make it more portable to other environments.
A Worker can be used to self-host applications that a user typically runs on Cloudflare Workers. According to Cloudflare, it must be a production-ready web server for this purpose.
The open source offering has been designed to be self-contained in the hosting environment so that it can fit into any server/VM/container hosting and orchestration system the user prefers. In addition, the worker is designed to facilitate realistic local testing of the Worker.
A Worker can also act as an application host, a proxy server, or both, and it supports both forward and reverse proxy models. JavaScript can be used to intercept and process requests and responses before they are transmitted.
Worker is currently available in beta. Interested users can click here to try. For more information read on blog post.