Cairn

Cairn is a self-hosted, persistent memory platform designed for both AI agents and humans. It serves as a long-term, cross-session memory store, enabling agents (and teams) to retain, query, and structure knowledge, decisions, and beliefs across projects and time. Featuring vector and keyword-based search, automated knowledge graph construction, multi-user authentication, code intelligence, and work management, it's aimed at systems thinkers and those needing a unified, persistent memory for both automated and human workflows. Cairn is now retired and archived; its successor is Rill.