--- Makefile.orig	2018-10-21 23:10:07.000000000 +0200
+++ Makefile	2018-11-07 00:22:00.872017000 +0100
@@ -3,6 +3,7 @@
 TESTS        = $(wildcard test/sql/*.sql)
 REGRESS      = $(patsubst test/sql/%.sql,%,$(TESTS))
 REGRESS_OPTS = --inputdir=test
+DOCS         = $(wildcard doc/*.md)
 MODULES      = $(patsubst %.c,%,$(wildcard *.c))
 PG_CONFIG    ?= pg_config