During May 2025, Alex Smart enhanced pattern matching error messages and type coverage analysis in the hazelgrove/hazel repository. Working in ReasonML, Alex refactored the type-coverage pattern generation logic, introducing new helpers to generate more robust pattern suggestions and clearer guidance for inexhaustive matches. This example-driven approach improved the accuracy and usability of error reporting, making it easier for developers to identify and resolve coverage gaps. Alex also applied formatting and readability improvements across the codebase, increasing maintainability. The work demonstrated depth in compiler development, pattern matching, and static analysis, directly reducing debugging time and improving the overall developer experience.