diff --git a/.cirrus.yml b/.cirrus.yml
index 3ef6079..34e28ec 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -1,3 +1,5 @@
+# This file is auto-generated by tools/cirrus_gen_yml.sh -- do not edit manually!
+
 release_linux_x86_64_download_docker_builder:
   timeout_in: 120m
   out_release_linux_x86_64_cache:
diff --git a/tools/cirrus_gen_yml.sh b/tools/cirrus_gen_yml.sh
index 42a2905..810b03e 100755
--- a/tools/cirrus_gen_yml.sh
+++ b/tools/cirrus_gen_yml.sh
@@ -153,6 +153,8 @@ print_os_arch () {
 }
 
 (
+echo "# This file is auto-generated by tools/cirrus_gen_yml.sh -- do not edit manually!"
+echo ""
 for CHANNEL in release; do
     print_os_arch linux x86_64
     print_os_arch linux i686