Worked on correctness and reliability improvements for a16z/jolt and extended Lean Batteries in leanprover-community/batteries. In Rust, addressed edge cases in signed remainder validation by refactoring calculation logic, aligning range checks, and expanding test coverage to ensure robust handling of 32-bit and 64-bit scenarios. For Lean, introduced the LawfulMonadLift class to support lawful lifting of monad transformers, ensuring that lifting operations preserved key properties when composing monads. Delivered a targeted fix to maintain commutativity with bind, reducing integration risk for developers. The work demonstrated depth in formal verification, functional programming, instruction set architecture, and type theory across both projects.