During March 2025, Thunig focused on improving simulation accuracy in the matsim-org/matsim-libs repository by addressing a regression in the QueueWithBuffer inflow capacity calculation. He reverted a previous change that incorrectly multiplied inflow capacity by the flow capacity factor, restoring the original maxFlowFromFdiag logic. This adjustment corrected simulation outcomes, particularly enhancing the accuracy of car mode share predictions. Thunig ensured code quality through comprehensive regression testing and code review, maintaining clear commit history and traceability. His work leveraged Java and simulation engineering expertise, demonstrating careful attention to both technical detail and the broader impact on transportation modeling reliability.