JavaOne 2026 Session

Summary

At CERN, Java has been at the core of business applications for almost three decades, with its first production Java system being released in 1998. The system lives on to this day. This long history means dealing with everything from aging monoliths to modern microservices, all coexisting and evolving under one roof. How does it all keep working, consistent, and productive for more than 80 developers across many teams?

This talk analyzes the strategies used to streamline & improve the developer experience: from standardizing development environments with templates and documentation to making onboarding painless through easy bootstrapping.

You'll also hear how CERN uses Gradle to boost productivity, with centralized build logic, build caching, custom repositories, and internal plugins all developed to address real-world issues in a codebase spanning generations. This talk offers a behind-the-scenes look at what it takes to keep 30 years of Java running smoothly.