diff --git a/miniupnpd/gitrev.mk b/miniupnpd/gitrev.mk
index fa09314..f1a529c 100644
--- a/miniupnpd/gitrev.mk
+++ b/miniupnpd/gitrev.mk
@@ -1,8 +1,23 @@
-# (c) 2019-2020 Thomas Bernard
+# (c) 2019-2021 Thomas Bernard
 # For GNU Make
 
+# CI_COMMIT_TAG / CI_COMMIT_BRANCH / CI_COMMIT_SHORT_SHA are gitlab-ci
+# predefined variables
+# see https://docs.gitlab.com/ee/ci/variables/predefined_variables.html
+ifneq ($(CI_COMMIT_TAG),)
+GITREF = $(CI_COMMIT_TAG)
+else
+ifneq ($(CI_COMMIT_BRANCH),)
+GITREF = $(CI_COMMIT_BRANCH)-$(CI_COMMIT_SHORT_SHA)
+else
 ISGITREPO := $(shell git rev-parse --is-inside-work-tree)
 ifeq ($(ISGITREPO),true)
+# <tag> or <branch>-<short commit ref>
 GITREF := $(shell git describe --exact-match --tags 2> /dev/null || echo "`git rev-parse --abbrev-ref HEAD`-`git rev-parse --short HEAD`" )
+endif
+endif
+endif
+
+ifneq ($(GITREF),)
 CPPFLAGS += -DMINIUPNPD_GIT_REF=\"$(GITREF)\"
 endif