During July 2025, Jean Lestel enhanced backend reliability and scalability across the home-assistant/core and teslamate-org/teslamate repositories. He implemented strict domain validation logic in Python for Tesla Fleet, reducing configuration errors by ensuring only valid domain formats are accepted. In teslamate-org/teslamate, he introduced dynamic HTTP connection pool sizing, allowing the system to adjust pool size based on fleet size and configurable environment variables, which improved performance for users managing large numbers of vehicles. His work demonstrated strong skills in API integration, configuration management, and backend development, addressing both feature delivery and bug resolution with a focus on operational robustness.