During May 2025, Mateusz Bach implemented a hierarchical threading option for the antmicro/verilator repository, enabling independent control over the number of threads used for scheduling hierarchical blocks. He designed and integrated a new command-line interface option, --hierarchical-threads, making core changes in C++ to decouple hierarchical and main thread counts within the simulation engine. This work leveraged his expertise in compiler development, multithreading, and SystemVerilog, and included comprehensive updates to both user and developer documentation. The feature addressed scalability and performance challenges in large hierarchical designs, demonstrating a focused and technically deep contribution to Verilator’s simulation capabilities.