Comment by Narishma

This is one of many Turbo Vision ports/clones.

There's also this one in C++: https://github.com/kloczek/tvision

The one that comes with FreePascal/Lazarus is written in Pascal.

There's even one in Rust, though it might have been vibe-coded: https://github.com/aovestdipaperino/turbo-vision-4-rust