During January 2026, contributed to both the google-deepmind/torax and rust-lang/rust repositories by expanding test coverage and strengthening verification for critical code paths. Developed targeted unit tests in Python for mathematical formulas within torax, validating volume integrals, peak locations, and output shapes to ensure formula correctness and reliability. In the rust-lang/rust repository, enhanced compiler optimization testing by introducing FileCheck annotations in Rust, verifying constant propagation and dead code elimination within the GVN optimization. These efforts improved maintainability and confidence in core components, with traceable commits supporting future regression checks and ongoing performance optimization across both projects.