diff --git a/Makefile b/Makefile
index 227101d..17fe872 100644
--- a/Makefile
+++ b/Makefile
@@ -24,6 +24,7 @@ all: clean missions server
 
 server:
 	@./rebar compile
+	rm src/egs_script_lexer.erl src/egs_script_parser.erl
 
 missions:
 	$(ERLC) src/psu/psu_parser.erl