Worked on the rems-project/cn repository, focusing on core compiler reliability and solver correctness over a two-month period. Addressed critical issues in C and OCaml by aligning offsetof handling with C standards, switching from sint to size_t for memory layout calculations, and expanding test coverage to ensure type safety. Further stabilized the SMT solver by resolving a regression in integer-to-u64 casting during array shift operations, introducing type-aware checks and regression tests to codify edge-case behavior. Emphasized static analysis and robust testing practices, delivering targeted fixes that improved cross-platform consistency and reduced production risk without introducing new features during this period.