diff --git a/graph-lib/Makefile b/graph-lib/Makefile
index efd3a26b..ff095c05 100644
--- a/graph-lib/Makefile
+++ b/graph-lib/Makefile
@@ -13,4 +13,4 @@ clean:
 .PHONY: build-dep
 build-dep:
 	# datatype is only used as an example in the docs.
-	raco pkg install --deps search-auto --update-deps --skip-installed alexis-util cover cover-coveralls debug datatype
+	raco pkg install --deps search-auto --update-deps --skip-installed alexis-util cover cover-coveralls debug datatype mischief