The Top 10 Authentication Open Source Projects

An open-source alternative to Firebase, this platform provides a full backend stack built on PostgreSQL — including authentication, real-time subscriptions, storage, and auto-generated APIs. It targets developers who want Firebase-like convenience without vendor lock-in or NoSQL constraints.

• Key strength: Combines a relational database with Firebase-style developer experience, making it easy to build production apps with row-level security and real-time capabilities out of the box.
• Caveat: Self-hosting requires managing PostgreSQL and multiple services, which adds operational complexity compared to fully managed backends.

A curated list of awesome Go frameworks, libraries and software

A reverse proxy that provides authentication with Google, Azure, OpenID Connect and many more identity providers.

appwrite is an open source backend platform that provides APIs and managed services for application development. The repository includes authentication, databases, storage, functions, messaging, and administrative tooling that can be self hosted. Appwrite is commonly used for web and mobile backends, prototypes, and teams building product features without custom infrastructure from scratch.

The Single Sign-On Multi-Factor portal for web apps, now OpenID Certified™

Open Source realtime backend in 1 file

Daemon to ban hosts that cause multiple authentication errors

hackathon-starter is a Node.js boilerplate project that bundles common web app patterns such as authentication, account management, database integration, and API examples. It provides starter structure and sample implementations for rapid application setup. The project is commonly used in hackathons, prototypes, student projects, and early-stage product experiments.

Open source alternative to Auth0 / Firebase Auth / AWS Cognito

The Web framework for perfectionists with deadlines.