Jailed uses native JavaScript functions to run other libraries in a sandboxed environment, which could be the route to safer plugins and better automated testing of code ...

Gitpod is an open source developer platform designed to work at automating the provisioning of ready-to-code developer environments for applications running in the cloud.

It allows developers to write and run Python code in HTML, and call Javascript libraries in PyScript. This system allows a website to be written entirely in Python.