diff --git a/Makefile b/Makefile
index c5f152042b..7b6d101649 100644
--- a/Makefile
+++ b/Makefile
@@ -38,8 +38,7 @@ postgres: postgres-configure
 	+@echo "Compiling PostgreSQL"
 	$(MAKE) -C tmp_install/build MAKELEVEL=0 install
 	+@echo "Compiling contrib/zenith"
-	(cd vendor/postgres/contrib/zenith && \
-	$(MAKE) PG_CONFIG=$(abspath tmp_install)/bin/pg_config install USE_PGXS=1)
+	$(MAKE) -C tmp_install/build/contrib/zenith install
 
 postgres-clean:
 	$(MAKE) -C tmp_install/build MAKELEVEL=0 clean