diff --git a/setup.sh b/setup.sh
index 9810680..df85e56 100755
--- a/setup.sh
+++ b/setup.sh
@@ -17,7 +17,7 @@ fi
 echo "Generating configuration with domain: $DOMAIN..."
 docker run -it --rm \
   -v $(pwd)/config/synapse:/data \
-  -e SYNAPSE_SERVER_NAME= "$DOMAIN" \
+  -e SYNAPSE_SERVER_NAME="$DOMAIN" \
   -e SYNAPSE_REPORT_STATS=no \
   matrixdotorg/synapse:latest generate