The trick from the linked post still seems to work for me. It has even installed an interpreter for a made-up lang, a mixture of Python and TypeScript, complete with the docs [1] and everything, and it was doing a pretty convincing job when I poked at its made-up REPL.
[1]: https://gist.github.com/notpushkin/de9ec3f4571a4d0074daa0ef6...