SAML Protocol Identity Provider Middleware

samlp is a Node.js middleware library designed to facilitate the creation of SAML Protocol Identity Provider (IdP) endpoints. It handles the complexities of generating SAML responses and metadata, allowing developers to focus on user authentication mechanisms. The current stable version is 8.0.0, released March 31, 2026. This library is actively maintained by Auth0 and sees releases for new features, bug fixes, and dependency updates, typically on a monthly to quarterly cadence. Its key differentiator is its focus specifically on the IdP side of SAML, providing a configurable Express/Koa-compatible middleware, in contrast to libraries that are more general-purpose or service provider-centric. It requires Node.js version 12 or greater, reflecting modern Node.js ecosystem practices.