Vaultwarden

Bitwarden is already an excellent password manager, and the company allows self-hosting. The problem is that the official server is a full .NET plus SQL Server stack and is fairly heavy to run.

That is Vaultwarden's value: the same API, rewritten in Rust, with a footprint small enough to ignore. 65,396 stars, AGPL-3.0. A Raspberry Pi or a container of a few dozen megabytes can hold the whole family's vault, and you keep using Bitwarden's official browser extensions and mobile apps — no client changes at all, just point the server URL at your own domain in settings.

Another point many people value: several of Bitwarden's paid features — TOTP code storage, attachments, organizations and shared collections — are all available here. This is not a crack; the project implements those APIs itself. If you rely on them, consider donating to both upstream Bitwarden and this project.

Some things must be stated seriously, because this is passwords:

• It is a community project, not an official Bitwarden product, and the depth of security auditing is not comparable to the hosted service. The vault itself is end-to-end encrypted (the server never sees plaintext), but the operational security of that server is now your job.
• HTTPS is mandatory, and do not expose it bare to the internet. The common approach is behind a reverse proxy, or reachable only on your LAN or Tailscale network.
• Back it up, repeatedly. Losing the database on that machine means losing every account credential at once.

If you have neither the appetite nor the experience for server maintenance, Bitwarden's official free hosted tier is the safer choice — its free allowance is ample for an individual. Vaultwarden is for people who specifically want to hold the keys themselves.