There's a Rust project (used to be OCaml iirc) that aims to be a better Git, it's called Pijul.
https://nest.pijul.com/pijul/pijul (self hosted, thus not on Github)
It uses the interesting Sanakirja db engine:
https://pijul.org/posts/2021-02-06-rethinking-sanakirja
https://docs.rs/sanakirja/1.0.1/sanakirja
When I look at the design goals of Evo, it seems to be more on the user ergonomics side. There have been many attempts to fix Git's UX; so there is probably some things about Git's UX that can be improved.