Worked on enhancing the robustness and performance of the HNSW-based semantic router in the vllm-project/semantic-router repository. Focused on improving the randomness source by replacing timestamp-based randomness with Go’s math/rand/v2 random number generator, which resulted in a more uniform level distribution within the HNSW index. This change led to reduced variance in recall and latency, providing more predictable caching behavior and a smoother user experience during route resolution. Demonstrated backend development and testing skills in Go, maintaining compatibility and comprehensive test coverage while refactoring a performance-critical path to improve reliability without introducing breaking changes to the existing API.