diff --git a/Makefile b/Makefile
index 15a946cf..653ff13e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-SPEC_GENERATOR_VER=1.3.2
+SPEC_GENERATOR_VER=1.4.0
 
 .PHONY: install