diff --git a/pkgs/by-name/mo/mo/package.nix b/pkgs/by-name/mo/mo/package.nix
index cd8d1c003d2a..e303dd2bc1ec 100644
--- a/pkgs/by-name/mo/mo/package.nix
+++ b/pkgs/by-name/mo/mo/package.nix
@@ -32,5 +32,6 @@ stdenv.mkDerivation rec {
     homepage = "https://github.com/tests-always-included/mo";
     license = lib.licenses.mit;
     maintainers = with lib.maintainers; [ sheepforce ];
+    mainProgram = "mo";
   };
 }