diff --git a/libultraship/Makefile b/libultraship/Makefile
index d6789db0b..58e0e1d1a 100644
--- a/libultraship/Makefile
+++ b/libultraship/Makefile
@@ -69,6 +69,7 @@ INC_DIRS := $(addprefix -I, \
 	libultraship/Lib/spdlog \
 	libultraship/Lib/spdlog/include \
 	libultraship \
+	../StormLib/src \
 )
 
 # create build directories