keyper

A self-hosted credential manager with zero-knowledge encryption, multi-user support, and emergency recovery. Store API keys, passwords, and secrets securely with your own database. Features AES-256-GCM encryption, Argon2 key derivation, PWA support, and professional-grade security architecture. Maintained by pinkpixel-dev on GitHub, where it has earned 106 stars from the community.

It's actively developed around aes, aes-encryption, api-keys, and is a solid reference for anyone building with these tools.