You can guess it is written in Rust before even checking the repo whenever you see that somebody made a clone of some popular systems tool like top, ls, cd, etc.
I know, right?! It's a common theme.
But recently, there were two submissions here that actually turn the "rewrite in Rust" meme into something substantial.
The two factions of C++ https://news.ycombinator.com/item?id=42231489 On "Safe" C++ https://news.ycombinator.com/item?id=42186475
Be warned that the second one is a really long read!
I, for one, have been wishing for a high-performance, extensible alternative to emacs for a long time.