Alexander Liemen enhanced the IPPL-framework/ippl repository by developing foundational unit test coverage for the particle module’s Gather/Scatter API. Focusing on C++ with Kokkos and MPI, he implemented GatherScatterTest.cpp to validate gather and scatter operations across multiple modes and policies. This work improved the module’s testability and maintainability, enabling more reliable regression protection and supporting safer future refactoring. By laying the groundwork for continuous integration of API validation, Alexander addressed the need for robust verification of core functionality in parallel computing environments. His contributions provided measurable improvements in code quality, setting the stage for broader test adoption within the project.