diff --git a/pkgs/applications/window-managers/river/default.nix b/pkgs/applications/window-managers/river/default.nix
index 53714a03c5c3..453dcf14d82e 100644
--- a/pkgs/applications/window-managers/river/default.nix
+++ b/pkgs/applications/window-managers/river/default.nix
@@ -86,6 +86,7 @@ stdenv.mkDerivation (finalAttrs: {
       fortuneteller2k
       rodrgz
     ];
+    mainProgram = "river";
     platforms = lib.platforms.linux;
   };
 })