See https://github.com/spring-projects/spring-framework/wiki/Downloading-Spring-artifacts[downloading Spring artifacts] for Maven repository information.
Extensive JavaDoc for the Spring Security code is also available in the https://docs.spring.io/spring-security/site/docs/current/api/[Spring Security API Documentation].
See https://docs.spring.io/spring-security/site/docs/5.3.x/reference/html5/#servlet-hello[Hello Spring Security] to get started with a "Hello, World" application.
https://help.github.com/articles/creating-a-pull-request[Pull requests] are welcome; see the https://github.com/spring-projects/spring-security/blob/master/CONTRIBUTING.md[contributor guidelines] for details.