And thou shalt remove your setup.py files and cast them out

extension_helpers/__init__.py

@@ -2,3 +2,17 @@
 from ._setup_helpers import get_compiler, get_extensions, pkg_config
 from ._utils import import_file, write_if_different
 from .version import version as __version__
+
+from configparser import ConfigParser
+
+
+def _finalize_distribution_hook(distribution):
+    """
+    Something something setuptools entrypoint
+    """
+    config_files = distribution.find_config_files()
+    cfg = ConfigParser()
+    cfg.read(config_files[0])
+    if cfg.has_option("extension_helpers", "use_extension_helpers") and cfg.get("extension_helpers", "use_extension_helpers"):
+        extension_helpers_cfg = cfg["extension_helpers"]
+        distribution.ext_modules = get_extensions(distribution=distribution)

extension_helpers/_setup_helpers.py

@@ -36,7 +36,7 @@ def get_compiler():
     return new_compiler().compiler_type
 
 
-def get_extensions(srcdir='.'):
+def get_extensions(srcdir='.', distribution=None):
     """
     Collect all extensions from Cython files and ``setup_package.py`` files.
 

setup.cfg

@@ -30,6 +30,10 @@ install_requires =
 [options.package_data]
 extension_helpers = src/compiler.c
 
+[options.entry_points]
+setuptools.finalize_distribution_options =
+    extension_helpers_get_extensions = extension_helpers:_finalize_distribution_hook
+
 [options.extras_require]
 test =
     pytest