diff --git a/lib/nulla/activitypub.ex b/lib/nulla/activitypub.ex
index 0f7dd73..838aae4 100644
--- a/lib/nulla/activitypub.ex
+++ b/lib/nulla/activitypub.ex
@@ -209,7 +209,7 @@ defmodule Nulla.ActivityPub do
 
   @spec webfinger(Actor.t()) :: Jason.OrderedObject.t()
   def webfinger(actor) do
-    data = [
+    Jason.OrderedObject.new(
       subject: "#{actor.preferredUsername}@#{actor.domain}",
       aliases: [
         "https://#{actor.domain}/@#{actor.preferredUsername}",
@@ -225,27 +225,14 @@ defmodule Nulla.ActivityPub do
           rel: "self",
           type: "application/activity+json",
           href: "https://#{actor.domain}/users/#{actor.preferredUsername}"
+        ),
+        Jason.OrderedObject.new(
+          rel: "http://webfinger.net/rel/avatar",
+          type: actor.icon.mediaType,
+          href: actor.icon.url
         )
       ]
-    ]
-
-    data =
-      if actor.icon do
-        Keyword.update!(data, :links, fn links ->
-          links ++
-            [
-              Jason.OrderedObject.new(
-                rel: "http://webfinger.net/rel/avatar",
-                type: Map.get(actor.icon, :mediaType),
-                href: Map.get(actor.icon, :url)
-              )
-            ]
-        end)
-      else
-        data
-      end
-
-    Jason.OrderedObject.new(data)
+    )
   end
 
   @spec nodeinfo(String.t()) :: Jason.OrderedObject.t()
diff --git a/lib/nulla/models/actor.ex b/lib/nulla/models/actor.ex
index d77fcb0..f1c58a1 100644
--- a/lib/nulla/models/actor.ex
+++ b/lib/nulla/models/actor.ex
@@ -29,8 +29,8 @@ defmodule Nulla.Models.Actor do
     field :tag, {:array, :map}, default: []
     field :attachment, {:array, :map}, default: []
     field :endpoints, :map
-    field :icon, :map
-    field :image, :map
+    field :icon, :map, default: %{}
+    field :image, :map, default: %{}
     field :vcard_bday, :date
     field :vcard_Address, :string
 
diff --git a/lib/nulla_web/controllers/webfinger_controller.ex b/lib/nulla_web/controllers/webfinger_controller.ex
index a36e6b3..cc7854f 100644
--- a/lib/nulla_web/controllers/webfinger_controller.ex
+++ b/lib/nulla_web/controllers/webfinger_controller.ex
@@ -5,13 +5,13 @@ defmodule NullaWeb.WebfingerController do
   alias Nulla.Models.InstanceSettings
 
   def index(conn, %{"resource" => resource}) do
-    case Regex.run(~r/^acct:(.+)@(.+)$/, resource) do
+    case Regex.run(~r/^acct:([^@]+)@(.+)$/, resource) do
       [_, username, domain] ->
         case Actor.get_actor(username, domain) do
           nil ->
             conn
-            |> put_resp_content_type("text/plain")
-            |> send_resp(404, "")
+            |> put_status(:not_found)
+            |> json(%{error: "Not Found"})
 
           %Actor{} = actor ->
             instance_settings = InstanceSettings.get_instance_settings!()
@@ -20,21 +20,15 @@ defmodule NullaWeb.WebfingerController do
               json(conn, ActivityPub.webfinger(actor))
             else
               conn
-              |> put_resp_content_type("text/plain")
-              |> send_resp(404, "")
+              |> put_status(:not_found)
+              |> json(%{error: "Not Found"})
             end
         end
 
       _ ->
         conn
-        |> put_resp_content_type("text/plain")
-        |> send_resp(400, "")
+        |> put_status(:bad_request)
+        |> json(%{error: "Bad Request"})
     end
   end
-
-  def index(conn, _params) do
-    conn
-    |> put_resp_content_type("text/plain")
-    |> send_resp(400, "")
-  end
 end
diff --git a/priv/repo/migrations/20250615130714_create_actors.exs b/priv/repo/migrations/20250615130714_create_actors.exs
index 8098ce9..da2ff37 100644
--- a/priv/repo/migrations/20250615130714_create_actors.exs
+++ b/priv/repo/migrations/20250615130714_create_actors.exs
@@ -26,8 +26,8 @@ defmodule Nulla.Repo.Migrations.CreateActors do
       add :tag, {:array, :map}, default: []
       add :attachment, {:array, :map}, default: []
       add :endpoints, :map
-      add :icon, :map
-      add :image, :map
+      add :icon, :map, default: %{}
+      add :image, :map, default: %{}
       add :vcard_bday, :date
       add :vcard_Address, :string
     end