--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -43,6 +43,7 @@ AM_TESTS_ENVIRONMENT = \
 TEST_EXTENSIONS = .vtc
 VTC_LOG_COMPILER = varnishtest -v -t 120
 AM_VTC_LOG_FLAGS = \
+    -D vmod_selector="$(VMOD_SELECTOR)" \
     -p vcl_path="$(abs_top_srcdir)/vcl:$(VARNISHAPI_VCLDIR)" \
     -p vmod_path="$(abs_builddir)/.libs:$(vmoddir):$(VARNISHAPI_VMODDIR)"
 
