diff --git a/lib/nulla/activitypub.ex b/lib/nulla/activitypub.ex
index 40410dd..fd50758 100644
--- a/lib/nulla/activitypub.ex
+++ b/lib/nulla/activitypub.ex
@@ -62,8 +62,8 @@ defmodule Nulla.ActivityPub do
     )
   end
 
-  @spec note(String.t(), Note.t()) :: Jason.OrderedObject.t()
-  def note(domain, note) do
+  @spec note(Note.t()) :: Jason.OrderedObject.t()
+  def note(note) do
     attachment =
       case note.media_attachments do
         [] ->
@@ -76,7 +76,7 @@ defmodule Nulla.ActivityPub do
                 Jason.OrderedObject.new(
                   type: "Document",
                   mediaType: att.mime_type,
-                  url: "https://#{domain}/files/#{att.file}"
+                  url: "https://#{note.actor.domain}/files/#{att.file}"
                 )
               end)
           ]
@@ -87,18 +87,18 @@ defmodule Nulla.ActivityPub do
         "https://www.w3.org/ns/activitystreams",
         Jason.OrderedObject.new(sensitive: "as:sensitive")
       ],
-      id: "https://#{domain}/users/#{note.actor.preferredUsername}/statuses/#{note.id}",
+      id: "#{note.actor.ap_id}/statuses/#{note.id}",
       type: "Note",
       summary: nil,
       inReplyTo: nil,
       published: note.inserted_at,
-      url: "https://#{domain}/@#{note.actor.preferredUsername}/#{note.id}",
-      attributedTo: "https://#{domain}/users/#{note.actor.preferredUsername}",
+      url: "#{note.actor.ap_id}/#{note.id}",
+      attributedTo: note.actor.ap_id,
       to: [
         "https://www.w3.org/ns/activitystreams#Public"
       ],
       cc: [
-        "https://#{domain}/users/#{note.actor.preferredUsername}/followers"
+        "#{note.actor.ap_id}/followers"
       ],
       sensetive: false,
       content: note.content,
@@ -107,11 +107,11 @@ defmodule Nulla.ActivityPub do
     )
   end
 
-  @spec activity(String.t(), Activity.t()) :: Jason.OrderedObject.t()
-  def activity(domain, activity) do
+  @spec activity(Activity.t()) :: Jason.OrderedObject.t()
+  def activity(activity) do
     Jason.OrderedObject.new(
       "@context": "https://www.w3.org/ns/activitystreams",
-      id: "https://#{domain}/activities/#{activity.id}",
+      id: activity.ap_id,
       type: activity.type,
       actor: activity.actor,
       object: activity.object
@@ -212,19 +212,19 @@ defmodule Nulla.ActivityPub do
     data = [
       subject: "#{actor.preferredUsername}@#{actor.domain}",
       aliases: [
-        "https://#{actor.domain}/@#{actor.preferredUsername}",
-        "https://#{actor.domain}/users/#{actor.preferredUsername}"
+        actor.url,
+        actor.ap_id
       ],
       links: [
         Jason.OrderedObject.new(
           rel: "http://webfinger.net/rel/profile-page",
           type: "text/html",
-          href: "https://#{actor.domain}/users/#{actor.preferredUsername}"
+          href: actor.url
         ),
         Jason.OrderedObject.new(
           rel: "self",
           type: "application/activity+json",
-          href: "https://#{actor.domain}/users/#{actor.preferredUsername}"
+          href: actor.ap_id
         )
       ]
     ]
@@ -295,21 +295,20 @@ defmodule Nulla.ActivityPub do
     )
   end
 
-  @spec outbox(String.t(), String.t(), Integer.t()) :: Jason.OrderedObject.t()
-  def outbox(domain, username, total) do
+  @spec outbox(Actor.t(), Integer.t()) :: Jason.OrderedObject.t()
+  def outbox(actor, total) do
     Jason.OrderedObject.new(
       "@context": "https://www.w3.org/ns/activitystreams",
-      id: "https://#{domain}/users/#{username}/outbox",
+      id: "#{actor.ap_id}/outbox",
       type: "OrderedCollection",
       totalItems: total,
-      first: "https://#{domain}/users/#{username}/outbox?page=true",
-      last: "https://#{domain}/users/#{username}/outbox?min_id=0&page=true"
+      first: "#{actor.ap_id}/outbox?page=true",
+      last: "#{actor.ap_id}/outbox?min_id=0&page=true"
     )
   end
 
-  @spec outbox(String.t(), Integer.t(), Integer.t(), String.t(), List.t()) ::
-          Jason.OrderedObject.t()
-  def outbox(domain, username, max_id, min_id, items) do
+  @spec outbox(Actor.t(), Integer.t(), Integer.t(), List.t()) :: Jason.OrderedObject.t()
+  def outbox(actor, max_id, min_id, items) do
     Jason.OrderedObject.new(
       "@context": [
         "https://www.w3.org/ns/activitystreams",
@@ -318,11 +317,11 @@ defmodule Nulla.ActivityPub do
           Hashtag: "as:Hashtag"
         )
       ],
-      id: "https://#{domain}/users/#{username}/outbox?page=true",
+      id: "#{actor.ap_id}/outbox?page=true",
       type: "OrderedCollectionPage",
-      next: "https://#{domain}/users/#{username}/outbox?max_id=#{max_id}&page=true",
-      prev: "https://#{domain}/users/#{username}/outbox?min_id=#{min_id}&page=true",
-      partOf: "https://#{domain}/users/#{username}/outbox",
+      next: "#{actor.ap_id}/outbox?max_id=#{max_id}&page=true",
+      prev: "#{actor.ap_id}/outbox?min_id=#{min_id}&page=true",
+      partOf: "#{actor.ap_id}/outbox",
       orderedItems: items
     )
   end
@@ -330,22 +329,20 @@ defmodule Nulla.ActivityPub do
   @spec activity_note(Note.t()) :: Jason.OrderedObject.t()
   def activity_note(note) do
     Jason.OrderedObject.new(
-      id:
-        "https://#{note.actor.domain}/users/#{note.actor.preferredUsername}/#{note.id}/activity",
+      id: "#{note.actor.ap_id}/statuses/#{note.id}/activity",
       type: "Create",
-      actor: "https://#{note.actor.domain}/users/#{note.actor.preferredUsername}",
+      actor: note.actor.ap_id,
       published: note.inserted_at |> DateTime.to_iso8601(),
       to: [
         "https://www.w3.org/ns/activitystreams#Public"
       ],
       object:
         Jason.OrderedObject.new(
-          id:
-            "https://#{note.actor.domain}/users/#{note.actor.preferredUsername}/statuses/#{note.id}",
+          id: "#{note.actor.ap_id}/statuses/#{note.id}",
           type: "Note",
           content: note.content,
           published: note.inserted_at |> DateTime.to_iso8601(),
-          attributedTo: "https://#{note.actor.domain}/users/#{note.actor.preferredUsername}",
+          attributedTo: note.actor.ap_id,
           to: [
             "https://www.w3.org/ns/activitystreams#Public"
           ]
diff --git a/lib/nulla_web/controllers/note_controller.ex b/lib/nulla_web/controllers/note_controller.ex
index 2b271be..c0237f5 100644
--- a/lib/nulla_web/controllers/note_controller.ex
+++ b/lib/nulla_web/controllers/note_controller.ex
@@ -3,12 +3,9 @@ defmodule NullaWeb.NoteController do
   alias Nulla.Repo
   alias Nulla.ActivityPub
   alias Nulla.Models.Note
-  alias Nulla.Models.InstanceSettings
 
   def show(conn, %{"username" => username, "id" => id}) do
     accept = List.first(get_req_header(conn, "accept"))
-    instance_settings = InstanceSettings.get_instance_settings!()
-    domain = instance_settings.domain
     note = Note.get_note!(id) |> Repo.preload([:user, :media_attachments])
 
     if username != note.user.username do
@@ -21,9 +18,9 @@ defmodule NullaWeb.NoteController do
     if accept in ["application/activity+json", "application/ld+json"] do
       conn
       |> put_resp_content_type("application/activity+json")
-      |> json(ActivityPub.note(domain, note))
+      |> json(ActivityPub.note(note))
     else
-      render(conn, :show, domain: domain, note: note, layout: false)
+      render(conn, :show, note: note, layout: false)
     end
   end
 end
diff --git a/lib/nulla_web/controllers/outbox_controller.ex b/lib/nulla_web/controllers/outbox_controller.ex
index 505a1fb..dffa3d8 100644
--- a/lib/nulla_web/controllers/outbox_controller.ex
+++ b/lib/nulla_web/controllers/outbox_controller.ex
@@ -38,7 +38,7 @@ defmodule NullaWeb.OutboxController do
         |> put_resp_content_type("application/activity+json")
         |> send_resp(
           200,
-          Jason.encode!(ActivityPub.outbox(domain, username, next_max_id, min_id || 0, items))
+          Jason.encode!(ActivityPub.outbox(actor, next_max_id, min_id || 0, items))
         )
 
       _ ->
@@ -49,7 +49,7 @@ defmodule NullaWeb.OutboxController do
 
         conn
         |> put_resp_content_type("application/activity+json")
-        |> send_resp(200, Jason.encode!(ActivityPub.outbox(domain, username, total)))
+        |> send_resp(200, Jason.encode!(ActivityPub.outbox(actor, total)))
     end
   end
 end