Hi. I've been working on this open-source projects last time:
ghstats[1] - self-hosted service to track & keep GitHub repos views (Rust)
macmon[2] - Apple M-series performance monitor in CLI with power metrics (Rust)
ecloop[3] - let say fast Bitcoin addresses checker by bloom filter (a lot of interesting math inside) (pure C)
[1] https://github.com/vladkens/ghstats