Over a two-month period, this developer focused on stabilizing and scaling test infrastructure across the facebook/buck2, facebook/metro, and githubnext/discovery-agent__facebook__react-native repositories. They resolved test deadlocks and enabled robust parallel execution by introducing Buck2 isolation directories and per-test build outputs, leveraging JavaScript and Node.js for integration with Jest and Metro. In Rust, they expanded Buck2’s gRPC worker request size limits to support large-scale test suites, aligning request handling for consistency and reliability. Their work improved test throughput, reduced flakiness, and eliminated manual workarounds, resulting in faster feedback loops and greater confidence in release pipelines for backend systems.