diff --git a/nixos/modules/services/networking/consul.nix b/nixos/modules/services/networking/consul.nix
index f7d2afead06..bfaea4e167c 100644
--- a/nixos/modules/services/networking/consul.nix
+++ b/nixos/modules/services/networking/consul.nix
@@ -99,6 +99,7 @@ in
 
       extraConfig = mkOption {
         default = { };
+        type = types.attrsOf types.anything;
         description = ''
           Extra configuration options which are serialized to json and added
           to the config.json file.