The ebuild lacks dependency to dev-python/semantic-version[${PYTHON_USEDEP}] Reproducible: Always Steps to Reproduce: 1.emerge pluggy without dev-python/semantic in the same python targets installed 2. 3. Actual Results: The build fails without or with the insufficient python versions. I set the use flags and emerge -1 dev-python/semantic-version to workaround. After that I compiled pluggy with success. Expected Results: (re)build dev-python/semantic-version first and build successfully.