diff --git a/install-wings.sh b/install-wings.sh
index 88dd706..7e4c922 100644
--- a/install-wings.sh
+++ b/install-wings.sh
@@ -252,8 +252,11 @@ if confirm_default_no "Run wings configure --join-data now?"; then
   JOIN_DATA="$(extract_join_data "$JOIN_DATA_RAW")"
 
   if [[ -n "$JOIN_DATA" ]]; then
-  $SUDO mkdir -p /etc/calagopus-wings
-    $SUDO "$WINGS_BIN" configure --join-data "$JOIN_DATA"
+    $SUDO mkdir -p /etc/calagopus-wings
+    # --override skips wings' interactive "overwrite existing config?" prompt.
+    # Without it, a re-run (or any pre-existing config.yml) makes wings try to
+    # read a confirm from stdin, which fails with "not a terminal" under curl|bash.
+    $SUDO "$WINGS_BIN" configure --join-data "$JOIN_DATA" --override
     CONFIG_CREATED=true
     say "Configuration complete"
   else