Excalibase is an open-source backend platform. Spin up a project and get a full stack instantly: Postgres (15/16/17), a MongoDB-compatible DocumentDB built on Postgres, auto-generated GraphQL + REST APIs, role-based permissions, realtime notifications, S3-compatible storage, Deno serverless functions, and container deploys — plus automatic backups with point-in-time restore. Runs on Kubernetes; free during beta.