Rapidly starting to think even a vibecoded solution may be a better plan relying on commercial options. High risk of don’t roll your own crypto mistakes but realistically that’s not the threat model here anymore for the random individual. It’s online breaches or perhaps a wrench attack not highly skilled crypto adversary. Plus there are probably ready made crypto modules so wouldn’t be a true handroll
I mean I'm just spitballing here, but not convinced this is true.
From a formal security theory perspective certainly, but practically...nobody with half an ounce of skill is going to spend their time breaking one individual's custom solution that almost certainly just contains their hn password. That's if you can even get to it - selfhosted password managers are usually on LAN/behind vpn.
Risk profile wise the thing could be a god damn plain text .txt on a LAN network drive and still outperform a Lastpass.com that by definition has a giant hack-me sign on it's back.
The crypto part barely moves the needles here
So while Bitwarden is more secure than modern Excel out of the box, neither one is a slouch. You'll definitely spend a lot of compute cracking either one. The weakest part, as always, is the user's password.
Especially if the concerns around Mythos are well founded.
The mythical Mythos can't even find Claude code bugs before releases.