diff --git a/make/templates.mk b/make/templates.mk
index edcf265a..f738db56 100644
--- a/make/templates.mk
+++ b/make/templates.mk
@@ -1,6 +1,45 @@
+
+#
+# Finds a file in a package and assigns it to the given variable.
+# Produces an evaluation-time error if the file could not be found.
+#
+# Example:
+#
+# $(eval $(call onlpm_find_file,KERNEL_4_14,onl-kernel-4.14-lts-x86-64-all:amd64,kernel-4.14-lts-x86_64-all))
+#
 define onlpm_find_file
 $(1) := $$(shell $(ONLPM) --find-file $(2) $(3))
 ifeq ($$($(1)),)
 $$(error $(2):$(3) not found)
 endif
 endef
+
+#
+# The --find-dir equivalent.
+#
+define onlpm_find_dir
+$(1) := $$(shell $(ONLPM) --find-dir $(2) $(3))
+ifeq ($$($(1)),)
+$$(error $(2):$(3) not found)
+endif
+endef
+
+
+#
+# Just like onlpm_find_{file,dir} but also add the result to another variable for easier aggregation.
+#
+define onlpm_find_file_add
+$(1) := $$(shell $(ONLPM) --find-file $(2) $(3))
+ifeq ($$($(1)),)
+$$(error $(2):$(3) not found)
+endif
+$(4) := $$($(4)) $$($(1))
+endef
+
+define onlpm_find_dir_add
+$(1) := $$(shell $(ONLPM) --find-file $(2) $(3))
+ifeq ($$($(1)),)
+$$(error $(2):$(3) not found)
+endif
+$(4) := $$($(4)) $$($(1))
+endef