Jérôme Leleu
Freelance at CAS in the cloud
Bordeaux, Nouvelle-Aquitaine, France
Summary
🤩
Rockstar🎓
Top SchoolJérôme Leleu is a freelance security engineer and open-source leader with nearly two decades of experience focused on authentication, SSO and identity protocols such as CAS, pac4j, OAuth, OpenID Connect and SAML. He is the creator of the pac4j security framework and a major contributor and committer to the Apereo CAS project, bringing deep hands-on expertise in token flows, session management and CSRF mitigation. Based in Bordeaux, he combines consultancy and remote expert missions with practical platform work—implementing CAS SaaS, integrating pac4j across frameworks like Ratpack and Shiro, and building production-ready Spring Boot services. His background includes leading identity teams at SFR, founding a CAS cloud offering, and delivering architecture and performance audits for Elasticsearch and MongoDB. Jérôme frequently bridges standards and implementations, having added Single Sign-Out support to the Apereo Java CAS client and implemented OAuth/OIDC improvements in CAS itself. He pairs architect-level thinking with active maintenance of security libraries, so clients get both strategy and reliable, audited code.
14 years of coding experience
9 years of employment as a software developer
Bac+5, Master’s Degree in Engineering, Bac+5, Master’s Degree in Engineering at Télécom SudParis
French, English
Stackoverflow
2,499reputation
147kreached
216answers
0questions
Github Skills (28)
authorizations10
back-end-development10
openid-connect10
testing10
it-security10
authentication10
user-authentication10
java10
security10
servlet10
javas10
authorization10
web-security10
oauth10
ratpack10
Programming languages (12)
Github contributions (5)
pac4j/pac4j
Jan 2012 - Jan 2023
Security engine for Java (authentication, authorization, multi frameworks): OpenID Connect, SAML2, CAS, OAuth, LDAP, JWT...
Role in this project:
Back-end Developer & Security Engineer
Back-end Developer & Security EngineerContributions:46 reviews, 3588 commits, 1705 PRs in 11 years 1 month
Contributions summary:Jérôme's contributions primarily focus on implementing security measures within the Java-based security engine, pac4j. They implemented and tested support for the CAS OAuth wrapper and improved the handling of OpenID Connect protocols, including the implementation of a token validator and the management of states and session indices. Furthermore, the user addressed vulnerabilities related to CSRF and ensured proper HTTP action handling and implemented OAuth 2.0 support.
authenticationauthorizationjavajwtldap
bujiio/buji-pac4j
Jul 2012 - Aug 2022
Bridge from the pac4j security library to Shiro
Role in this project:Back-end Developer
Back-end DeveloperContributions:246 commits, 261 PRs, 403 pushes in 10 years 3 months
Contributions summary:Jérôme primarily focused on updating the project by adding license information, adding `@since` tags, and updating the `maven-bundle-plugin` configuration in the `buji-pac4j` repository. The code modifications involve changes to several Java files within the project, including filter implementations and a test class. These modifications aimed to improve the project's structure and maintainability, especially with the addition of comments in the code base.
pac4jsecurityjavashiroauthentication
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.