Stef worked on the bazelbuild/bazel repository, focusing on improving the reliability of test coverage collection during flaky test retries. By addressing a critical incompatibility, Stef modified the Java-based build system to skip coverage collection on failed attempts and clear stale metadata after sandbox cleanup. This approach prevented FileNotFoundException errors and stabilized the continuous integration pipeline by reducing failures caused by lingering metadata. Stef’s work enhanced the accuracy of coverage reporting and contributed to faster, less noisy feedback cycles. The solution demonstrated a strong understanding of software testing and test automation, delivering a targeted fix that improved Bazel’s CI stability.