diff --git a/v0/include.mk b/v0/include.mk
index bc390ad..b81c728 100644
--- a/v0/include.mk
+++ b/v0/include.mk
@@ -1,4 +1,4 @@
-V0_SRC := v0/main.c v0/token.c v0/parser.c v0/log.c
+V0_SRC := v0/main.c v0/util.c v0/token.c v0/parser.c v0/log.c
 
 # V0_TEST must only include `v0/test.c` itself, as all other test C–source files are
 # included directly into `v0/test.c` using `#include "test_xyz.c"`.