diff --git a/passepartout b/passepartout
index fb7d337..fdf8d3a 100755
--- a/passepartout
+++ b/passepartout
@@ -406,6 +406,10 @@ case "$COMMAND" in
   (sleep 3) (finish-output) (uiop:quit 1))))
   (passepartout.channel-tui:tui-main))
 LISPEOF
+        # Capture terminal dimensions in non-standard env vars
+        # (SBCL strips COLUMNS/LINES but leaves MY_* alone).
+        local ts=$(stty size 2>/dev/null)
+        export MY_TERM_LINES="${ts%% *}" MY_TERM_COLS="${ts##* }"
         # Clear stale cl-tty cache to ensure latest backend-size fixes
         find ~/.cache/common-lisp -name "*.fasl" -path "*cl-tty*" -delete 2>/dev/null
         exec sbcl --noinform --load /tmp/tui-load.lisp