During October 2025, Wataru Imai enhanced path prefix rewriting for root paths in the DataDog/cilium repository, focusing on backend development with Go and comprehensive testing. He updated the Envoy configuration logic to ensure that leading slashes are preserved during prefix rewrites, addressing issues with root-path matches that previously led to misrouting. By refining the pathPrefixMutation function and introducing regression tests, Wataru improved routing accuracy for services dependent on root-path configurations. His work emphasized deterministic configuration rewrites and robust test coverage, contributing to more reliable production deployments and reducing the risk of routing errors in complex backend environments.