diff --git a/make.sh b/make.sh
index f273625..0061a75 100644
--- a/make.sh
+++ b/make.sh
@@ -5,4 +5,5 @@ gcc `find src/ -name '*.c'` \
 	submodules/utilitiec/build/lib/liballocator-interface.a \
 	submodules/utilitiec/build/lib/libStringView.a \
 	submodules/utilitiec/build/lib/libScratchpad.a \
+	-Isubmodules/utilitiec/src \
 	-lm -ggdb -Wall -Wextra -pedantic -o bin/flup
diff --git a/test-inputs/factorial.flup b/test-inputs/factorial.flup
new file mode 100644
index 0000000..1e6e681
--- /dev/null
+++ b/test-inputs/factorial.flup
@@ -0,0 +1,6 @@
+factorial: int n -> int
+	| n 0 == -> 1
+	| 1      -> n 1 - factorial n * duplicate println
+	;
+
+25 factorial