diff --git a/flake.nix b/flake.nix
index 92cf3b0..2a62bf2 100644
--- a/flake.nix
+++ b/flake.nix
@@ -110,7 +110,7 @@
             type = "app";
             program = "${self'.packages.lispers}/bin/rt_interp";
           };
-          default = self'.apps.rt_lisp_lisp;
+          default = self'.apps.rt_lisp_demo;
         };
 
         devShells.default = pkgs.mkShell {