diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2f0a297..c552e1c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,7 +16,10 @@ endif ()
 add_subdirectory(dependencies/libcsptr/ EXCLUDE_FROM_ALL)
 add_subdirectory(dependencies/dyncall/ EXCLUDE_FROM_ALL)
 
-include_directories(SYSTEM /usr/local/include)
+include_directories(SYSTEM
+  /usr/local/include
+  /usr/include/GNUStep
+)
 
 include_directories(
   dependencies/libcsptr/include/