diff --git a/contrib/teamcity/build-configurations.sh b/contrib/teamcity/build-configurations.sh
--- a/contrib/teamcity/build-configurations.sh
+++ b/contrib/teamcity/build-configurations.sh
@@ -4,6 +4,7 @@
 
 set -euxo pipefail
 
+: ${ABC_BUILD_NAME:=""}
 if [ -z "$ABC_BUILD_NAME" ]; then
   echo "Error: Environment variable ABC_BUILD_NAME must be set"
   exit 1