Worked on the pydantic/pydantic repository to enhance build system reliability by addressing a key issue in the Makefile configuration. Focused on restoring the default build target to 'all', this change ensured that both local development and continuous integration environments produced consistent, reproducible builds. The technical approach involved modifying the Makefile using Makefile syntax and build system configuration skills, specifically by uncommenting the .DEFAULT_GOAL assignment. This adjustment aligned the build process with standard conventions, reducing potential confusion for contributors. The work was documented with a clear commit message and linked to the relevant issue, providing traceability and clarity for future maintenance.