Neat. I'm curious, which problems did you have with existing password managers that made you write your own? You mention Lastpass and mitro in the REAMDE, but there are lots of other good options available, like KeePass or Bitwarden.
I got fed up with switching these services so often and didn't want to do the same thing yet again (and can't remember what alternatives existed back then).
Since security has been my point of interest for years I decided to look into building my own so that I would actually know for sure (as long as cryptography itself is secure) about all the parts - how secrets are encrypted, how they're stored and how they're synced. It was spring 2015 when I wrote my first password manager in Ruby. It worked great, but the problem was that I didn't want to install Ruby and its gems on every system where I wanted to access my secrets so I went with Go and this is where secrets-cli (https://github.com/jarmo/secrets-cli/) grew up. After that I decided that I'd also want to access secrets via browser and created secrets-web (https://github.com/jarmo/secrets-web/). Web and CLI versions are interoperable between each-other so that you can use either one of them or both at the same time.