Java Spring Codebase Upgrade
Budget: €12 – €18 EUR
I’m migrating an older Java backend—built on legacy Spring and Hibernate—into a fresh Spring Boot 3 project so the stack is fully modern and future-proof. The focus is code refactoring: untangling dated patterns, replacing XML configuration with annotations, adopting Spring Data JPA, and cleaning up any deprecated API usage. No new features are needed right now; the goal is pure code modernization.
You’ll receive a private Git repo containing the current application and a lightweight skeleton for the new one. Work incrementally, push frequent commits, and raise pull requests so the migration stays transparent and reviewable. GitHub Actions is already wired, so every PR should keep the build green.
Deliverables
• A runnable Spring Boot 3.x application that preserves all existing business logic
• Updated entity mappings compatible with Hibernate 6 and JPA annotations
• Refactored service layer following current Spring patterns and best practices
• A concise migration guide highlighting major structural changes and any breaking points
Acceptance Criteria
• Application starts cleanly without deprecation warnings
• All existing integration tests pass against PostgreSQL 15
• Code complies with google-java-format and shows zero issues on SonarLint
If you’ve successfully lifted legacy Java projects onto modern Spring stacks before, I’m ready to give you access to the repo and outline the first milestone.
You’ll receive a private Git repo containing the current application and a lightweight skeleton for the new one. Work incrementally, push frequent commits, and raise pull requests so the migration stays transparent and reviewable. GitHub Actions is already wired, so every PR should keep the build green.
Deliverables
• A runnable Spring Boot 3.x application that preserves all existing business logic
• Updated entity mappings compatible with Hibernate 6 and JPA annotations
• Refactored service layer following current Spring patterns and best practices
• A concise migration guide highlighting major structural changes and any breaking points
Acceptance Criteria
• Application starts cleanly without deprecation warnings
• All existing integration tests pass against PostgreSQL 15
• Code complies with google-java-format and shows zero issues on SonarLint
If you’ve successfully lifted legacy Java projects onto modern Spring stacks before, I’m ready to give you access to the repo and outline the first milestone.