diff --git a/skimage/morphology/_skel.pyx b/skimage/morphology/_skel.pyx.in
similarity index 100%
rename from skimage/morphology/_skel.pyx
rename to skimage/morphology/_skel.pyx.in
diff --git a/skimage/morphology/setup.py b/skimage/morphology/setup.py
index 5a26ac52..6d572ec6 100644
--- a/skimage/morphology/setup.py
+++ b/skimage/morphology/setup.py
@@ -16,7 +16,7 @@ def configuration(parent_package='', top_path=None):
     cython(['_skeletonize_cy.pyx'], working_path=base_path)
     cython(['_convex_hull.pyx'], working_path=base_path)
     cython(['_greyreconstruct.pyx'], working_path=base_path)
-    cython(['_skel.pyx'], working_path=base_path)
+    cython(['_skel.pyx.in'], working_path=base_path)
 
     config.add_extension('_watershed', sources=['_watershed.c'],
                          include_dirs=[get_numpy_include_dirs()])