I once implemented something like forth, in a tutorial-based fashion based on a thread I found on hacker news:

https://github.com/skx/foth

As per the original post this would be "user-level" not "hacker-level". I keep meaning to go back and do it properly, but instead I hacked up a simple Z80-based implementation and exhausted my interest in forth for the moment.

Seems like this post duplicates https://news.ycombinator.com/item?id=45039301