+# README.adoc exists because that filename is magic on GitLab.
+DOCS=COPYING NEWS README.adoc TODO advent.adoc history.adoc hints.adoc advent.6
+
+# Can't use GNU tar's --transform, needs to build under Alpine Linux.
+# This is a requirement for testing dist in GitLab's CI pipeline
+advent-$(VERS).tar.gz: $(SOURCES) $(DOCS)
+ @find $(SOURCES) $(DOCS) tests -print | sed s:^:advent-$(VERS)/: >MANIFEST
+ @(ln -s . advent-$(VERS))
+ (tar -T MANIFEST -czvf advent-$(VERS).tar.gz)
+ @(rm advent-$(VERS))