I had a good time being involved with a couple JavaScript runtimes which didn't make this list, most notably PythonMonkey [1] which embeds SpiderMonkey into Python and uses Python's event loop for its async stuff. Another interesting one was DCP which is sort of a pseudo js runtime that runs ontop of other js runtimes (including a custom sandboxed server-side runtime we made [3], but also any web browser), to provide cloud function like compute for js and wasm based workloads.

Unrelated to the article, and already well known, is Pyodide which is a Python runtime in JS/WASM. I shoved Pyodide into DCP so people could run Python workloads in web browsers [4]. Crazy stuff...

1. https://pythonmonkey.io/ 2. https://distributive.network/workers 3. https://gitlab.com/Distributed-Compute-Protocol/dcp-native 4. https://willpringle.ca/blog/dcp/pyodide-worktime/

My analysis on the polyglot runtimes was relatively shallow and I did anticipate I might disappoint, sorry! Thanks for the additions!

I did begin a section on WASM runtimes, so Pyodide would've been of interest, but I could see the scope was likely to grow too much if I got into WASM so I held back.