2024-12 Monthly Summary — mongodb/mongo-c-driver Overview: In December, the repository delivered two high-impact features that enhance security control and broaden platform support, providing tangible business value through configurable encryption behavior and expanded deployment options. The work included alignment with documentation and tests to ensure quality and maintainability. Key features and outcomes: - Data Encryption Key (DEK) cache expiration configuration: Introduced APIs to configure DEK cache lifetime in milliseconds, enabling finer control over encryption performance and security. This supports use-case-specific tuning for latency and resource usage. Commit: b0edf300b8623bc8a4d861f02aaefc8c312c46c9 (CDRIVER-5644). - Documentation and tests updated to reflect the new DEK cache configuration, ensuring consistent usage guidance and test coverage. - Unofficial ARM64 Windows support: Added ARM64 Windows support by updating CMake and test code, linking necessary Windows libraries, and adjusting exception handling to enable the driver to run on ARM64 Windows. Commit: e71642a4b4cd964f1d3b91e753af6c43971956ac (CDRIVER-5839). Major bugs fixed: - None reported this month. Overall impact and accomplishments: - Expanded platform reach by enabling ARM64 Windows builds, broadening potential customer deployments. - Provided a tunable DEK cache lifetime API to optimize encryption performance and security posture on supported workloads. - Improved developer experience and confidence through updated documentation and tests aligned with new features. Technologies/skills demonstrated: - Cross-platform build configurations and ARM64 Windows adaptations (CMake, Windows libraries) - API design and versioned feature work for encryption key management (DEK cache lifetime) - Documentation and test strategy alignment for feature delivery

In 2024-11, the team focused on enhancing encryption configurability and strengthening test coverage for Data Encryption Keys (DEKs) in Client-Side Encryption. The major effort delivered a configurable DEK cache lifetime, along with aligning tests and docs to the updated behavior, ensuring robust validation of the new option and its impact on encryption workflows.