diff --git a/Makefile b/Makefile
index edff811..c2a24c1 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-IGNORED = .jekyll-metadata Gemfile.lock _site
+IGNORED := $(shell grep -v testenv .gitignore)
 VOLUME_ARG =
 
 .PHONY: all