This package does not support Python 3.12. Please test it with Python 3.12 as a matter of urgency as the default will change in early June, as per message on gentoo-dev: https://www.mail-archive.com/gentoo-dev@lists.gentoo.org/msg99104.html. Ask in #gentoo-python on IRC if need any help. $ pkgcheck scan -k PythonCompatUpdate dev-python/marshmallow_enum dev-python/marshmallow_enum PythonCompatUpdate: version 1.5.1: PYTHON_COMPAT update available: python3_12