Maciej Turło focused on improving instrumentation reliability for feature toggles in the Unleash/yggdrasil repository during July 2025. He addressed a critical bug affecting feature toggle metrics by ensuring that metrics now count toggles based on their enabled status, rather than simply tracking whether a variant was returned. This change, implemented across both Java and WASM engines, required updating the underlying logic and expanding test coverage to validate the new approach. By refining the backend metric calculations and enhancing test reliability, Maciej’s work improved the accuracy of analytics used for feature rollout decisions and capacity planning, demonstrating strong backend and testing skills.