The article provides a comprehensive guide on managing Java monorepos, focusing on their structure, tools, and optimization techniques. It explains that while monorepos simplify code management compared to polyrepos, they still require careful setup, especially in Java ecosystems. The article details how to establish a monorepo using tools like Apache Maven, Gradle, Bazel, and Earthly, with an emphasis on Maven for build automation and dependency management. It guides the reader through creating a Maven archetype to enforce a standardized project structure, refining monorepo setups, and optimizing builds with Earthly, which helps manage resources efficiently through caching and Docker integration. The piece concludes by discussing the benefits and challenges of monorepos, suggesting that utilizing Earthly for build and CI/CD operations can mitigate some of these challenges by streamlining build times and improving resource utilization.