diff --git a/tests/wl-smoke-test.sh b/tests/wl-smoke-test.sh
index d49b612..5f5aa87 100755
--- a/tests/wl-smoke-test.sh
+++ b/tests/wl-smoke-test.sh
@@ -114,7 +114,10 @@
 #      WMAKER_WAYLAND_NESTED=1 (uses wlr_wl_backend + wlr_multi_backend),
 #      headless mode otherwise.  Scene nodes added for each XDG/XWayland
 #      surface so client content is composited into the output frame.
-#      Verified by "scene graph created" + "headless compositor mode" logs.
+#      Phase 18 fix: scene and output_layout created before wlr_backend_start
+#      so handle_backend_new_output finds a valid scene when it fires.
+#      Verified by "scene graph created" + "scene output created" +
+#      "headless compositor mode" logs.
 #  39. (Phase 17) XWayland started: wlr_xwayland_create() is called in
 #      wl_display_open(); compositor logs "XWayland started DISPLAY=:<n>"
 #      so X11 clients (GNUstep apps) can connect.  DISPLAY env var is set.
@@ -287,7 +290,10 @@ grep -q 'scene graph created' /tmp/wl-smoke-stderr \
 # Verify headless compositor mode (WMAKER_WAYLAND_NESTED not set in test)
 grep -q 'headless compositor mode' /tmp/wl-smoke-stderr \
     || die "compositor did not log headless compositor mode"
-echo "  scene check: scene graph created (headless compositor mode)"
+# Verify scene_output was created in handle_backend_new_output (ordering fix)
+grep -q 'scene output created' /tmp/wl-smoke-stderr \
+    || die "compositor did not log scene output creation (scene was NULL in new_output handler)"
+echo "  scene check: scene graph created + scene_output wired (headless compositor mode)"
 
 # -- 5. Core Wayland globals must be advertised ---------------------------
 #