Tom Daffurn worked on the TBD54566975/ftl repository, focusing on optimizing the build process by refactoring stub generation in Go. He redesigned the build pipeline so that stub generation occurs only once per build, rather than multiple times within the build loop, which previously led to redundant operations and potential inconsistencies. By moving stub generation to a single stage before the topological sort, Tom improved both the efficiency and reliability of the build system. His work demonstrated strong skills in build systems, code generation, and refactoring, resulting in a more maintainable and predictable continuous integration and build environment.