On: Z80 REPL (2018)

The source code for this is apparently 8 years old: https://github.com/abagames/z80-repl

With that said, I love the idea.

That makes me love it even more

Yea, it doesn't have that... uninspired design to it, looks like the design of someone who actually created it themselves.

Kenta Cho has created hundreds of games and toys over the past 20+ years. A lot of brilliant stuff.