Attila Hegyeli worked on the DSA_courses_for_teamwork repository, focusing on improving correctness and reliability in the project’s build and algorithmic components. He addressed a bug in the isPrime function, ensuring it accurately identifies prime numbers, which is essential for coursework and team exercises. Attila also enhanced the build process by updating the CMakeLists.txt configuration, adding necessary directories and setting the build type to Debug for better local debugging and reproducibility. His work utilized C and CMake, demonstrating attention to both algorithmic accuracy and build system robustness, though the scope was limited to targeted bug fixes rather than new feature development.