diff --git a/Makefile b/Makefile
index 9f90261..9b9185c 100644
--- a/Makefile
+++ b/Makefile
@@ -1,11 +1,13 @@
 .PHONY: default
 
+libs = lib/Parser.h lib/VerbLib.h lib/Grammar.h
+
 default: remontel.ulx remontel.z5
 
-remontel.ulx: remontel.inf includes/*.inf lib/Parser.h lib/VerbLib.h lib/Grammar.h
+remontel.ulx: remontel.inf includes/*.inf $(libs)
 	inform -G +include_path=includes,lib $<
 
-remontel.z5: remontel.inf includes/*.inf lib/Parser.h lib/VerbLib.h lib/Grammar.h
+remontel.z5: remontel.inf includes/*.inf $(libs)
 	inform +include_path=includes,lib $<
 
 lib/%.h: