Ivan focused on stabilizing and maintaining core infrastructure in the facebook/fbthrift and facebook/buck2-prelude repositories, addressing critical issues in build and test reliability. He reverted changes to serialization dependencies in C++ protocol tests, restoring module includes and ensuring test suite compatibility. In buck2-prelude, Ivan rolled back a dependency upgrade in BUCK build scripts, resolving integration issues and preserving CI stability. His work emphasized disciplined version control, careful rollback procedures, and thorough validation of test coverage. Leveraging skills in C++, Protocol Buffers, and build system configuration, Ivan prioritized reproducibility and maintenance, delivering depth in infrastructure reliability over new feature development.