Dear Maintainer, changing this line:
export PYBUILD_TEST_ARGS = mkdir {build_dir}/.tmp; cp -a {dir}/compressor/tests/static {build_dir}/.tmp/static; env TMP_TEST_DIR={build_dir}/.tmp {interpreter} -m coverage run --branch --source=compressor /usr/bin/django-admin test --settings=compressor.test_settings compressor to: export PYBUILD_BEFORE_TEST = mkdir {build_dir}/.tmp; cp -a {dir}/compressor/tests/static {build_dir}/.tmp/static export PYBUILD_TEST_ARGS = env TMP_TEST_DIR={build_dir}/.tmp {interpreter} -m coverage run --branch --source=compressor /usr/bin/django-admin test --settings=compressor.test_settings compressor export PYBUILD_AFTER_TEST = rm -rf {build_dir}/.tmp in debian/rules solves the issue. Adding: COMPRESS_MTIME_DELAY = 0.1 in compressor/test_settings.py also works. Maybe the cache does need to be flushed after each step in the python3 version loop. I don't know the internal structure of this package, I apologize if I misunderstood something. Kind Regards