diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index a1bc92893f..008966cae4 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -99,10 +99,10 @@ test:osx:
   parallel:
     matrix:
       - jobname: osx-clang
-        image: macos-13-xcode-14
+        image: macos-14-xcode-15
         CC: clang
       - jobname: osx-reftable
-        image: macos-13-xcode-14
+        image: macos-14-xcode-15
         CC: clang
   artifacts:
     paths:
diff --git a/ci/lib.sh b/ci/lib.sh
index 930f98d722..5440eb6dc0 100755
--- a/ci/lib.sh
+++ b/ci/lib.sh
@@ -18,7 +18,8 @@ elif test true = "$GITLAB_CI"
 then
 	begin_group () {
 		need_to_end_group=t
-		printf "\e[0Ksection_start:$(date +%s):$(echo "$1" | tr ' ' _)[collapsed=true]\r\e[0K$1\n"
+		printf '\e[0Ksection_start:%s:%s[collapsed=true]\r\e[0K%s\n' \
+			"$(date +%s)" "$(echo "$1" | tr ' ' _)" "$1"
 		trap "end_group '$1'" EXIT
 		set -x
 	}
@@ -27,7 +28,8 @@ then
 		test -n "$need_to_end_group" || return 0
 		set +x
 		need_to_end_group=
-		printf "\e[0Ksection_end:$(date +%s):$(echo "$1" | tr ' ' _)\r\e[0K\n"
+		printf '\e[0Ksection_end:%s:%s\r\e[0K\n' \
+			"$(date +%s)" "$(echo "$1" | tr ' ' _)"
 		trap - EXIT
 	}
 else
@@ -55,8 +57,7 @@ group () {
 	return $res
 }
 
-begin_group "CI setup"
-trap "end_group 'CI setup'" EXIT
+begin_group "CI setup via $(basename $0)"
 
 # Set 'exit on error' for all CI scripts to let the caller know that
 # something went wrong.
@@ -394,5 +395,5 @@ esac
 
 MAKEFLAGS="$MAKEFLAGS CC=${CC:-cc}"
 
-end_group "CI setup"
+end_group "CI setup via $(basename $0)"
 set -x