diff --git a/collects/launcher/launcher-sig.ss b/collects/launcher/launcher-sig.ss
index 689b354a95..6101935a3e 100644
--- a/collects/launcher/launcher-sig.ss
+++ b/collects/launcher/launcher-sig.ss
@@ -17,6 +17,9 @@
      install-mred-program-launcher
      install-mzscheme-program-launcher
 
+     mred-launcher-up-to-date?
+     mzscheme-launcher-up-to-date?
+
      current-launcher-variant
      available-mred-variants
      available-mzscheme-variants)))