diff --git a/pkgs/sagemath-standard/setup.py b/pkgs/sagemath-standard/setup.py
index 7ac2294b609..368fad8b037 100755
--- a/pkgs/sagemath-standard/setup.py
+++ b/pkgs/sagemath-standard/setup.py
@@ -44,13 +44,11 @@
     from sage_setup.setenv import setenv
     setenv()
 
-    from sage_setup.command.sage_build import sage_build
     from sage_setup.command.sage_build_cython import sage_build_cython
     from sage_setup.command.sage_build_ext import sage_build_ext
     from sage_setup.command.sage_install import sage_develop, sage_install_and_clean
 
-    cmdclass = dict(build=sage_build,
-                    build_cython=sage_build_cython,
+    cmdclass = dict(build_cython=sage_build_cython,
                     build_ext=sage_build_ext,
                     develop=sage_develop,
                     install=sage_install_and_clean)
@@ -76,6 +74,10 @@
     python_modules = []
     cython_modules = []
 else:
+    log.info("Generating auto-generated sources")
+    from sage_setup.autogen import autogen_all
+    autogen_all()
+
     # TODO: This should be quiet by default
     print("Discovering Python/Cython source code....")
     t = time.time()
diff --git a/src/sage_setup/command/sage_build.py b/src/sage_setup/command/sage_build.py
deleted file mode 100644
index 229af4292fb..00000000000
--- a/src/sage_setup/command/sage_build.py
+++ /dev/null
@@ -1,37 +0,0 @@
-# Import setuptools before importing distutils, so that setuptools
-# can replace distutils by its own vendored copy.
-import setuptools
-
-from distutils import log
-from distutils.command.build import build
-
-class sage_build(build):
-    sub_commands = [('build_cython', lambda *args: True)] + build.sub_commands
-
-    def run_autogen(self):
-        """
-        Generate auto-generated sources.
-
-        This must be done before building the python modules,
-        see :trac:`22106`.
-        """
-        from sage_setup.autogen import autogen_all
-        from sage_setup.find import find_python_sources
-        from sage.env import SAGE_SRC
-
-        log.info("Generating auto-generated sources")
-
-        pkgs = autogen_all()
-        python_packages, python_modules, cython_modules = find_python_sources(
-            SAGE_SRC, [ pkg.replace('.', '/') for pkg in pkgs])
-
-        for pkg in python_packages:
-            if pkg not in self.distribution.packages:
-                self.distribution.packages.append(pkg)
-
-        for cython_module in cython_modules:
-            self.distribution.ext_modules.append(cython_module)
-
-    def run(self):
-        self.run_autogen()
-        build.run(self)