diff --git a/kitty/launcher/main.c b/kitty/launcher/main.c
index 10e4ca3d0..bdee1fe18 100644
--- a/kitty/launcher/main.c
+++ b/kitty/launcher/main.c
@@ -5,6 +5,7 @@
  * Distributed under terms of the GPL3 license.
  */
 
+#define PY_SSIZE_T_CLEAN
 #include <libgen.h>
 #ifdef __APPLE__
 #include <mach-o/dyld.h>