diff --git a/cython/setup.py.in b/cython/setup.py.in
index ed02372d8..c35e54079 100644
--- a/cython/setup.py.in
+++ b/cython/setup.py.in
@@ -7,7 +7,7 @@ except ImportError:
 
 if 'SETUP_PY_NO_CHECK' not in os.environ:
     script_path = os.path.abspath(os.path.realpath(__file__))
-    install_path = os.path.abspath(os.path.realpath(os.path.join('${GTSAM_CYTHON_INSTALL_PATH}', 'setup.py')))
+    install_path = os.path.abspath(os.path.realpath(os.path.join('${GTSAM_CYTHON_INSTALL_PATH}${GTSAM_BUILD_TAG}', 'setup.py')))
     if script_path != install_path:
         print('setup.py is being run from an unexpected location: "{}"'.format(script_path))
         print('please run `make install` and run the script from there')