Apereo CAS - Identity & Single Sign On for all earthlings and beyond.
OpenID Connect (OIDC) identity and OAuth 2.0 provider with pluggable connectors
一账通是一款开源的统一身份认证授权管理解决方案，支持多种标准协议(LDAP, OAuth2, SAML, OpenID)，细粒度权限控制，完整的WEB管理功能，钉钉、企业微信集成等，QQ group: 167885406
Node.js library for SAML SSO
Login.gov Core App: Identity Provider (IdP)
This is a MongoDB provider for the ASP.NET Core 2 Identity framework
A turnkey OAuth & authentication system, designed for both Cloudflare Workers and Node.js
[UNMAINTAINED] Serverless Authentication as a Service (AaaS) provider built on top of AWS Cognito
Ruby SAML Identity Provider, best used with Rails (though not required)
A centralized login and SSO application to authenticate several websites and mobile apps.
Building blocks for servers implementing Simple Cloud Identity Management v2
A ranked list of awesome Digital Identity open source projects
Spring Boot OAuth 2.0 & OpenID Connect Identity Provider / Authorization Server
Mountable Rails engine that provides OpenID server/identity provider functionality
Get up and running quickly with Okta's OAuth as a Service and your favorite API Gateway.
OAuth 2.0 & OIDC Auth Server and Identity Provider
Projeto Login Cidadão