-%-download: FORCE
- $(MAKE) -C $(patsubst %-download,%,$@) download
-
-%-prepare: $(TARGET_DIR) FORCE
- $(MAKE) -C $(patsubst %-prepare,%,$@) prepare
-
-%-compile: %-prepare
- $(MAKE) -C $(patsubst %-compile,%,$@) compile
+%-prepare %-prereq %-download %-clean: FORCE
+else
+%-prepare %-prereq %-download %-clean %-compile %-install: FORCE
+endif
+ $(MAKE) -j1 -C $* $(patsubst $*-%,%,$@)