Open source authorization projects
Every project in the registry tagged authorization, ranked by real GitHub adoption.
Take control of your identity with a secure, flexible solution
Apache Casbin: an authorization library that supports access control models like ACL, RBAC, ABAC.
✨ 开源、免费、一站式 Java 权限认证框架，让鉴权变得简单、优雅！—— 登录认证、权限认证、分布式 Session 会话、微服务网关鉴权、SSO 单点登录、OAuth2.0 统一认证、jwt 集成、API Key 秘钥授权、API 参数签名
Internet-scale OpenID Certified™ OpenID Connect and OAuth2.1 provider that integrates with your user management through headless APIs. Solve OIDC/OAuth2 user ca
Secure, customizable identity infrastructure for developers
Secure, seamless authentication for modern applications
Open Policy Agent (OPA) is an open source, general-purpose policy engine.
Expose your FastAPI endpoints as Model Context Protocol (MCP) tools, with Auth!
Apereo CAS - Identity & Single Sign On for all earthlings and beyond.
Open Source, Google Zanzibar-inspired database for scalably storing and querying fine-grained authorization data
Modular auth, payments, emails, and analytics for your product
Build scalable authorization in minutes, not months
Secure, scalable API key management for developers
Secure, policy-based access control for modern applications
Easy integration with OAuth 2.0 service providers.
Modern data layer for TypeScript apps - type-safe ORM, built-in access control, automatic query services
Security engine for Java (authentication, authorization, multi frameworks): OpenID Connect, SAML2, CAS, OAuth, LDAP, JWT...
SpringBoot single sign-on authentication and authorization, implemented with OAuth 2.0, supporting cross-domain and distributed deployment.
🔐 Authentication, Authorization, and Accounting (AAA) App and Plugin for Caddy v2. 💎 Implements Form-Based, Basic, Local, LDAP, OpenID Connect, OAuth 2.0 (Git
A distributed single-sign-on framework.（单点登录框架XXL-SSO）
Welcome to the WSO2 Identity Server source code! For info on working with the WSO2 Identity Server repository and contributing code, click the link below.
An execution-authority gateway for AI agents and APIs. It intercepts consequential HTTP actions, asks Decionis whether they are authorized, and forwards exactly
Related tags
Frequently asked questions
How many open source authorization projects are there?
This registry tracks 22 projects tagged authorization, with 197,193 GitHub stars between them. The most-adopted is Authentik at 26,194 stars.
Are these authorization projects free to use?
Yes — 19 of the 22 carry an explicit open-source licence across 5 distinct licences, so there is no licence fee. Where a project also sells a hosted or enterprise version, the self-hosted path remains free.
Which authorization project should I choose?
The list above is ranked by GitHub stars, but stars measure attention rather than fit. Check three things on each card: the licence (permissive versus copyleft), the language it is written in, and the last-push date — a high-star project that has not been pushed in a year is a liability.
Are these authorization projects still maintained?
20 of the 22 were pushed in the last 90 days, and every card shows its exact last-push date so you can see the rest. Sort your shortlist by that date before committing to a migration.