diff --git a/Makefile b/Makefile
index bb613e73..18e903b4 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,8 @@
+.ONESHELL:
+.DELETE_ON_ERROR:
+MAKEFLAGS += --warn-undefined-variables
+MAKEFLAGS += --no-builtin-rules
+
 PROJECT = tildefriends
 BUILD_DIR ?= out
 BUILD_TYPES := debug release windebug winrelease