Hi, Keycloak implements OpenID Connect and SAML specifications from both client and server perspective. You can find some diagrams related to those specs on the web. Client (adapters) code is inside "integration" module and it's submodules. Then in "core" module is some shared code for both adapters and server. The rest of the code are mainly server parts. For the server, you can start to look at KeycloakApplication class, which is entry point where are registered REST resources and KeycloakSessionFactory, which registers SPIs. That's for the start. For the rest, I would suggest to dig into code, debug and see how it works :-) ah, and some startup docs for developers is also in readme files under "misc" directory (you can take a look at least to HackingOnKeycloak.md and Testsuite.md ). Good luck:-) Marek On 15.5.2015 06:41, Carlos Feria wrote: