diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index a11ac299bccd7..e059a8dbe413d 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2539,8 +2539,8 @@ with pkgs;
   mkspiffs-presets = recurseIntoAttrs (callPackages ../tools/filesystems/mkspiffs/presets.nix { });
 
   mobilizon = callPackage ../servers/mobilizon {
-    elixir = elixir_1_15;
-    beamPackages = beamPackages.extend (self: super: { elixir = elixir_1_15; });
+    elixir = beam.packages.erlang_26.elixir_1_15;
+    beamPackages = beam.packages.erlang_26.extend (self: super: { elixir = self.elixir_1_15; });
     mobilizon-frontend = callPackage ../servers/mobilizon/frontend.nix { };
   };