1 files changed, 1 insertions, 0 deletions
diff --git a/nixpkgs/nixos/modules/services/x11/display-managers/default.nix b/nixpkgs/nixos/modules/services/x11/display-managers/default.nix
index 92b3af8527f1..a5db3dd5dd45 100644
--- a/nixpkgs/nixos/modules/services/x11/display-managers/default.nix
+++ b/nixpkgs/nixos/modules/services/x11/display-managers/default.nix
@@ -219,6 +219,7 @@ in
 
       session = mkOption {
         default = [];
+        type = types.listOf types.attrs;
         example = literalExpression
           ''
             [ { manage = "desktop";