Keybase

Keybase is a cross-platform key directory and secure communications platform that uses public-key cryptography to bind online identities to cryptographic keys. It enables end-to-end encrypted chat, secure file storage, and team collaboration. The service combines a public key directory with proof-based identity verification, allowing users to prove ownership of social media accounts and other online identities so that others can verify control of a given key.

Key features include end-to-end encrypted messaging and file sharing, a versioned encrypted file system called KBFS (Keybase File System), and a team-centered workspace. The platform supports proofs tying a user’s key to identities across platforms (for example Twitter, GitHub, Reddit) and provides a client-side cryptographic workflow for key management and recovery. Keybase also offers desktop and mobile clients as well as a command-line interface, and has open-source components such as the cryptographic libraries and KBFS.

In terms of security, Keybase emphasizes client-side encryption, with private keys stored on user devices and never sent in plaintext to the server; the server facilitates coordination but cannot read end-to-end encrypted content. The project relies on a public key infrastructure and social proofs to facilitate trust in keys without relying solely on a central authority.

Keybase was launched in 2014 and was acquired by Zoom Video Communications in 2020, after which it continued to operate as a subsidiary and maintained its open-source components. The service remains focused on privacy-preserving identity, messaging, and data storage for individuals and teams.