During March 2026, Schan focused on enhancing the testability and telemetry infrastructure within the temporalio/sdk-core repository. He developed a conditional compilation pathway for the WorkerTelemetry struct using Rust, enabling test-only telemetry metrics to be isolated from production code. This approach introduced a dedicated helper and change gates, allowing developers to validate telemetry behavior without impacting production stability. By leveraging backend development skills and Rust’s compilation features, Schan’s work reduced risk during testing and streamlined the validation process for telemetry instrumentation. The depth of this contribution lies in its careful separation of test and production concerns, improving overall code maintainability.