Worked on the maximhq/bifrost repository to enhance provider configuration integrity and API reliability. Developed a Provider Update Validation Guard in Go, ensuring that PUT requests to provider endpoints reject key configurations, thereby preventing silent data loss and enforcing a per-key update model. Addressed cache coherence issues by refining how provider config updates interact with in-memory storage, reducing the risk of stale data. Added comprehensive unit tests to validate guard behavior and edge cases involving empty or absent keys. These changes improved backend robustness, clarified the API contract, and provided clearer client feedback, leveraging skills in API design, backend development, and unit testing.