Recursively clean CMake build directories

February 5, 2026

CMake build directories might contain 100s of megabytes of files for large projects. Over time, a developer computer might contain forgotten build directories that waste disk space. With Python, a script using send2trash allows safe removal of CMake build directories by first moving them to the OS trash/recycle bin. In distinction from shutil.rmtree, this send2trash approach allows recovery of files if the deletion was accidental. The heuristic used to detect a CMake build directory was inspired by ctest_empty_binary_directory.