Vaultwarden

Vaultwarden is an unofficial reimplementation of the Bitwarden server API, written in Rust instead of the original .NET stack. The key implication: you run your own password manager backend that all official Bitwarden clients connect to as if it were the real service. The iOS app, Android app, browser extensions, and desktop clients work without modification. Your vault data lives on your server, not Bitwarden’s.

The resource difference from the official server is substantial. The official Bitwarden server is a .NET application that typically needs 1GB or more of RAM to run comfortably. Vaultwarden handles the same client traffic in roughly 10MB. That means it runs on a Raspberry Pi, on a VPS with 512MB RAM, or alongside other containers on shared hardware without noticeable overhead.

The feature coverage is complete for personal and small-team use. Organisations, collections, user groups, TOTP authentication, password sharing, and attachment storage all work. The only meaningful limitations are at the enterprise end: audit logging is basic and there is no official support contract.

The HTTPS requirement is worth stating clearly. Bitwarden clients will not connect to a Vaultwarden instance over plain HTTP. You need a valid certificate on the domain before the apps will work. A Traefik or Caddy reverse proxy with Let’s Encrypt handles this automatically and is the standard setup.

Vaultwarden is not officially endorsed by Bitwarden. The Bitwarden clients connect to it because it accurately implements the API, but a client update could theoretically change the API in a way that breaks compatibility. In practice, this has not been a recurring problem.

Vaultwarden: Pros & Cons