InfoQ - Large Concept Models https://www.infoq.com InfoQ Large Concept Models feed Uber Migrates 75,000+ Test Classes from Junit 4 to Junit 5 Using Automated Code Transformation https://www.infoq.com/news/2026/04/uber-junit4-junit5-migration/?utm_campaign=infoq_content&utm_source=infoq&utm_medium=feed&utm_term=Large+Concept+Models <img src="https://res.infoq.com/news/2026/04/uber-junit4-junit5-migration/en/headerimage/generatedHeaderImage-1776546803798.jpg"/><p>Uber engineers migrated over 75,000 test classes from JUnit 4 to JUnit 5 using automated code transformation with OpenRewrite and internal orchestration. By enabling the JUnit Platform for dual execution with Bazel and validating changes through CI, the team modernized testing infrastructure while maintaining correctness at monorepo scale.</p> <i>By Leela Kumili</i> Large Concept Models Test Automation JUnit Unit Testing Productivity Orchestration Bazel AI Coding migration Developer Experience AI Development Development Architecture & Design AI, ML & Data Engineering news Mon, 27 Apr 2026 14:07:00 GMT https://www.infoq.com/news/2026/04/uber-junit4-junit5-migration/?utm_campaign=infoq_content&utm_source=infoq&utm_medium=feed&utm_term=Large+Concept+Models Leela Kumili 2026-04-27T14:07:00Z /news/2026/04/uber-junit4-junit5-migration/en