diff --git a/MANIFEST.in b/MANIFEST.in
index 9ec4e0b6c9ba6323d76b145c7d5400ebc1f7936d..741d4f2fae70983e30da70ccbc8e7ddb997b06f1 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,5 +1,7 @@
 include README.md
 include COPYING.txt
 include RELEASE-VERSION
+global-include *.pyx
+global-exclude phasefield/simplex_projection.c
 include versioneer.py
 include lbmpy/_version.py