Open-source toolkit for AI memory that scales

Open-source toolkit for AI memory that scales

Lithium is an open-source storage engine designed for AI agents to navigate, store, and retrieve structured data with precision. Built on PostgreSQL's ltree extension, it offers hierarchical, versioned, and scoped data management. Unlike vector databases or graph traversals, Lithium provides deterministic, index-backed queries (e.g., 'give me everything under engineering.auth') with built-in immutable versioning. It includes a TypeScript API with Result types for error handling, MCP (Model Context Protocol) integration for AI tools like Claude Code, Cursor, and Windsurf, and hooks for extensibility. The toolkit supports fast setup via npx and manual installation, making it ideal for AI applications requiring exact structured memory.