diff --git a/runner_scripts/root/config.sh b/runner_scripts/root/config.sh
index 0f5e727b1a6d3d55913bb4eed0953001bf3a60ee..c1d54cc3f8fb3ffab87e6589627133ce61735421 100755
--- a/runner_scripts/root/config.sh
+++ b/runner_scripts/root/config.sh
@@ -2,6 +2,9 @@
 set -euf -o pipefail
 shopt -s inherit_errexit
 
+: "${CUSTOM_ENV_AUTH_USER:?"AUTH_USER CI/CD variable has not been set."}"
+: "${CUSTOM_ENV_AUTH_KEY:?"AUTH_KEY secret CI/CD variable has not been set."}"
+
 AUTH_USER_WORK=$(runuser "$AUTH_USER" --login --command "echo \$WORK")
 
 : "${AUTH_USER_WORK:?"Could not determine $AUTH_USER's \$WORK directory."}"