diff --git a/MANIFEST.in b/MANIFEST.in
index 6b2e857..d4915a9 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,2 +1,3 @@
+recursive-include httptools *.pxd *.pyx
 recursive-include vendor *.c *.h LICENSE* README*
 include MANIFEST.in LICENSE