Pretty good overview of better-than-average to top-notch software, in terms of security and privacy (note that there are also service providers and tools listed on this page that I would neither endorse nor recommend):
Unofficial Bitwarden compatible server written in Rust
An interesting project if you want to self-host your own Bitwarden compatible server, written in Rust instead of in C#:
Unofficial Bitwarden compatible server written in Rust
(/ht https://news.ycombinator.com/item?id=41243147)
(Disclaimer: Keep in mind that every software, also formally verified one, can contain bugs, also security bugs.)