diff --git a/lib/architex.ex b/lib/architex.ex
index 414248f..67c9608 100644
--- a/lib/architex.ex
+++ b/lib/architex.ex
@@ -154,16 +154,6 @@ defmodule Architex do
     |> Enum.into(%{})
   end
 
-  @doc """
-  Serialize and encode the given struct.
-  """
-  @spec serialize_and_encode(struct()) :: {:ok, String.t()} | {:error, Jason.EncodeError.t()}
-  def serialize_and_encode(struct) do
-    struct
-    |> to_serializable_map()
-    |> encode_canonical_json()
-  end
-
   @doc """
   Add a signature to the given map under the `:signatures` key.
 
diff --git a/lib/architex/encodable_map.ex b/lib/architex/encodable_map.ex
index 5c67439..96c2f77 100644
--- a/lib/architex/encodable_map.ex
+++ b/lib/architex/encodable_map.ex
@@ -1,7 +1,6 @@
 # https://github.com/michalmuskala/jason/issues/69
 defmodule Architex.EncodableMap do
   alias Architex.EncodableMap
-  alias Architex.Types.{UserId, RoomId, EventId, GroupId, AliasId}
 
   defstruct pairs: []
 
@@ -15,12 +14,6 @@ defmodule Architex.EncodableMap do
     pairs =
       map
       |> Enum.map(fn
-        {k, v}
-        when is_struct(v, UserId) or is_struct(v, RoomId) or is_struct(v, EventId) or
-               is_struct(v, GroupId) or is_struct(v, AliasId) ->
-          # Simply convert IDs to a string.
-          {k, to_string(v)}
-
         {k, v} when is_map(v) ->
           {k, from_map(v)}
 
diff --git a/lib/architex/room_server.ex b/lib/architex/room_server.ex
index da567b8..d32ae55 100644
--- a/lib/architex/room_server.ex
+++ b/lib/architex/room_server.ex
@@ -398,7 +398,7 @@ defmodule Architex.RoomServer do
     end
   end
 
-  @spec insert_single_event(Room.t(), t(), Event.t()) ::
+  @spec insert_single_event(Room.t(), t(), %Event{}) ::
           (() -> {t(), Room.t(), Event.t()} | {:error, atom()})
   defp insert_single_event(room, state_set, event) do
     fn ->
@@ -472,7 +472,7 @@ defmodule Architex.RoomServer do
   # Get the events for room creation as dictated by the given preset.
   # TODO: trusted_private_chat:
   #       All invitees are given the same power level as the room creator.
-  @spec room_creation_preset(Account.t(), String.t() | nil, Room.t()) :: [Event.t()]
+  @spec room_creation_preset(Account.t(), String.t() | nil, Room.t()) :: [%Event{}]
   defp room_creation_preset(account, nil, %Room{visibility: visibility} = room) do
     preset =
       case visibility do
@@ -505,7 +505,7 @@ defmodule Architex.RoomServer do
   # - Content hash
   # - Event ID
   # - Signature
-  @spec finalize_and_insert_event(Event.t(), t(), Room.t()) ::
+  @spec finalize_and_insert_event(%Event{}, t(), Room.t()) ::
           {:ok, t(), Room.t(), Event.t()} | {:error, atom()}
   defp finalize_and_insert_event(
          event,
@@ -516,6 +516,7 @@ defmodule Architex.RoomServer do
       event
       |> Map.put(:auth_events, auth_events_for_event(event, state_set))
       |> Map.put(:prev_events, forward_extremities)
+      |> Map.put(:depth, get_depth(forward_extremities))
 
     case Event.post_process(event) do
       {:ok, event} -> authenticate_and_insert_event(event, state_set, room)
@@ -523,8 +524,17 @@ defmodule Architex.RoomServer do
     end
   end
 
+  @spec get_depth([String.t()]) :: integer()
+  defp get_depth(prev_event_ids) do
+    Event
+    |> where([e], e.id in ^prev_event_ids)
+    |> select([e], e.depth)
+    |> Repo.all()
+    |> Enum.max(fn -> 0 end)
+  end
+
   # Get the auth events for an events.
-  @spec auth_events_for_event(Event.t(), t()) :: [{String.t(), String.t()}]
+  @spec auth_events_for_event(%Event{}, t()) :: [Event.t()]
   defp auth_events_for_event(%Event{type: "m.room.create"}, _), do: []
 
   defp auth_events_for_event(
diff --git a/lib/architex/schema/event.ex b/lib/architex/schema/event.ex
index e924ae8..6a6bccf 100644
--- a/lib/architex/schema/event.ex
+++ b/lib/architex/schema/event.ex
@@ -6,76 +6,58 @@ defmodule Architex.Event do
   alias Architex.{Repo, Room, Event, Account, EncodableMap, KeyServer}
   alias Architex.Types.UserId
 
-  # TODO: It seems unsigned is always set, even though it is not specified?
+  # TODO: It seems unsigned is always set in DB, even though it is not specified?
   @type t :: %__MODULE__{
-          type: String.t(),
-          origin_server_ts: integer(),
-          state_key: String.t() | nil,
-          sender: UserId.t(),
-          content: map(),
-          prev_events: [String.t()] | nil,
+          nid: integer(),
+          id: String.t(),
           auth_events: [String.t()],
-          unsigned: map() | nil,
-          signatures: map() | nil,
-          hashes: map() | nil
+          content: map(),
+          depth: integer(),
+          hashes: map(),
+          origin: String.t(),
+          origin_server_ts: integer(),
+          prev_events: [String.t()],
+          redacts: String.t() | nil,
+          room_id: String.t(),
+          sender: UserId.t(),
+          signatures: map(),
+          state_key: String.t() | nil,
+          type: String.t(),
+          unsigned: map() | nil
         }
 
-  @primary_key {:nid, :id, autogenerate: true}
+  @primary_key false
   schema "events" do
-    field :type, :string
-    field :origin_server_ts, :integer
-    field :state_key, :string
-    field :sender, UserId
-    field :content, :map
-    field :prev_events, {:array, :string}
-    field :auth_events, {:array, :string}
-    field :unsigned, :map
-    field :signatures, {:map, {:map, :string}}
-    field :hashes, {:map, :string}
+    field :nid, :id, primary_key: true, autogenerate: true
     field :id, :string
 
+    # PDU fields
+    field :auth_events, {:array, :string}
+    field :content, :map
+    field :depth, :integer
+    field :hashes, {:map, :string}
+    field :origin, :string
+    field :origin_server_ts, :integer
+    field :prev_events, {:array, :string}
+    field :redacts, :string
     belongs_to :room, Room, type: :string
+    field :sender, UserId
+    field :signatures, {:map, {:map, :string}}
+    field :state_key, :string
+    field :type, :string
+    field :unsigned, :map
   end
 
-  # TODO: Move this to a dedicated function in Event.Formatters.
-  defimpl Jason.Encoder, for: Event do
-    @pdu_keys [
-      :auth_events,
-      :content,
-      :depth,
-      :hashes,
-      :origin,
-      :origin_server_ts,
-      :prev_events,
-      :redacts,
-      :room_id,
-      :sender,
-      :signatures,
-      :state_key,
-      :type,
-      :unsigned
-    ]
-
-    def encode(event, opts) do
-      event
-      |> Map.take(@pdu_keys)
-      |> Map.update!(:sender, &Kernel.to_string/1)
-      |> Jason.Encode.map(opts)
-    end
-  end
-
-  @spec new(Room.t(), Account.t()) :: %Event{}
   def new(%Room{id: room_id}, %Account{localpart: localpart}) do
     %Event{
       room_id: room_id,
       sender: %UserId{localpart: localpart, domain: Architex.server_name()},
       origin_server_ts: DateTime.utc_now() |> DateTime.to_unix(:millisecond),
-      prev_events: [],
-      auth_events: []
+      origin: Architex.server_name()
     }
   end
 
-  @spec custom_message(Room.t(), Account.t(), String.t(), map()) :: t()
+  @spec custom_message(Room.t(), Account.t(), String.t(), map()) :: %Event{}
   def custom_message(room, sender, type, content) do
     %Event{
       Event.new(room, sender)
@@ -224,7 +206,7 @@ defmodule Architex.Event do
   defp calculate_content_hash(event) do
     m =
       event
-      |> Architex.to_serializable_map()
+      |> Architex.Event.Formatters.as_pdu()
       |> Map.drop([:unsigned, :signature, :hashes])
       |> EncodableMap.from_map()
 
@@ -233,11 +215,10 @@ defmodule Architex.Event do
     end
   end
 
-  @spec redact(t()) :: map()
   defp redact(%Event{type: type, content: content} = event) do
     redacted_event =
       event
-      |> Architex.to_serializable_map()
+      |> Architex.Event.Formatters.as_pdu()
       |> Map.take([
         :id,
         :type,
diff --git a/lib/architex/schema/event/formatters.ex b/lib/architex/schema/event/formatters.ex
index 02407ca..15a17e5 100644
--- a/lib/architex/schema/event/formatters.ex
+++ b/lib/architex/schema/event/formatters.ex
@@ -1,6 +1,10 @@
 defmodule Architex.Event.Formatters do
+  @moduledoc """
+  Functions to format events in order to convert them to JSON.
+  """
   alias Architex.Event
 
+  @spec for_client(Event.t()) :: map()
   def for_client(%Event{
         content: content,
         type: type,
@@ -23,4 +27,42 @@ defmodule Architex.Event.Formatters do
 
     data
   end
+
+  @spec as_pdu(Event.t()) :: map()
+  def as_pdu(%Event{
+        auth_events: auth_events,
+        content: content,
+        depth: depth,
+        hashes: hashes,
+        origin: origin,
+        origin_server_ts: origin_server_ts,
+        prev_events: prev_events,
+        redacts: redacts,
+        room_id: room_id,
+        sender: sender,
+        signatures: signatures,
+        state_key: state_key,
+        type: type,
+        unsigned: unsigned
+      }) do
+    data = %{
+      auth_events: auth_events,
+      content: content,
+      depth: depth,
+      hashes: hashes,
+      origin: origin,
+      origin_server_ts: origin_server_ts,
+      prev_events: prev_events,
+      room_id: room_id,
+      sender: to_string(sender),
+      signatures: signatures,
+      type: type
+    }
+
+    data = if redacts, do: Map.put(data, :redacts, redacts), else: data
+    data = if state_key, do: Map.put(data, :state_key, state_key), else: data
+    data = if unsigned, do: Map.put(data, :unsigned, unsigned), else: data
+
+    data
+  end
 end
diff --git a/lib/architex/schema/event/generators.ex b/lib/architex/schema/event/generators.ex
index 92bae47..abb52ad 100644
--- a/lib/architex/schema/event/generators.ex
+++ b/lib/architex/schema/event/generators.ex
@@ -1,7 +1,7 @@
 defmodule Architex.Event.Join do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t()) :: Event.t()
+  @spec new(Room.t(), Account.t()) :: %Event{}
   def new(room, %Account{localpart: localpart} = sender) do
     mxid = Architex.get_mxid(localpart)
 
@@ -19,7 +19,7 @@ end
 defmodule Architex.Event.CreateRoom do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, %Account{localpart: localpart} = creator, room_version) do
     mxid = Architex.get_mxid(localpart)
 
@@ -38,7 +38,7 @@ end
 defmodule Architex.Event.PowerLevels do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t()) :: Event.t()
+  @spec new(Room.t(), Account.t()) :: %Event{}
   def new(room, %Account{localpart: localpart} = sender) do
     mxid = Architex.get_mxid(localpart)
 
@@ -69,7 +69,7 @@ end
 defmodule Architex.Event.Name do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, sender, name) do
     %Event{
       Event.new(room, sender)
@@ -85,7 +85,7 @@ end
 defmodule Architex.Event.Topic do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, sender, topic) do
     %Event{
       Event.new(room, sender)
@@ -101,7 +101,7 @@ end
 defmodule Architex.Event.JoinRules do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, sender, join_rule) do
     %Event{
       Event.new(room, sender)
@@ -117,7 +117,7 @@ end
 defmodule Architex.Event.HistoryVisibility do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, sender, history_visibility) do
     %Event{
       Event.new(room, sender)
@@ -133,7 +133,7 @@ end
 defmodule Architex.Event.GuestAccess do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, sender, guest_access) do
     %Event{
       Event.new(room, sender)
@@ -149,7 +149,7 @@ end
 defmodule Architex.Event.Invite do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, sender, user_id) do
     %Event{
       Event.new(room, sender)
@@ -165,7 +165,7 @@ end
 defmodule Architex.Event.Leave do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t()) :: Event.t()
+  @spec new(Room.t(), Account.t()) :: %Event{}
   def new(room, sender) do
     %Event{
       Event.new(room, sender)
@@ -181,7 +181,7 @@ end
 defmodule Architex.Event.Kick do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t(), String.t() | nil) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t(), String.t() | nil) :: %Event{}
   def new(room, sender, user_id, reason \\ nil) do
     content = %{"membership" => "leave"}
     content = if reason, do: Map.put(content, "reason", reason), else: content
@@ -198,7 +198,7 @@ end
 defmodule Architex.Event.Ban do
   alias Architex.{Event, Account, Room}
 
-  @spec new(Room.t(), Account.t(), String.t(), String.t() | nil) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t(), String.t() | nil) :: %Event{}
   def new(room, sender, user_id, reason \\ nil) do
     content = %{"membership" => "ban"}
     content = if reason, do: Map.put(content, "reason", reason), else: content
@@ -214,7 +214,7 @@ end
 
 defmodule Architex.Event.Unban do
   alias Architex.{Event, Account, Room}
-  @spec new(Room.t(), Account.t(), String.t()) :: Event.t()
+  @spec new(Room.t(), Account.t(), String.t()) :: %Event{}
   def new(room, sender, user_id) do
     %Event{
       Event.new(room, sender)
diff --git a/lib/architex/schema/room.ex b/lib/architex/schema/room.ex
index 24fc07c..74a31eb 100644
--- a/lib/architex/schema/room.ex
+++ b/lib/architex/schema/room.ex
@@ -4,7 +4,7 @@ defmodule Architex.Room do
   import Ecto.Changeset
   import Ecto.Query
 
-  alias Architex.{Repo, Room, Event, Alias, RoomServer}
+  alias Architex.{Repo, Room, Event, Alias, RoomServer, Account}
   alias ArchitexWeb.Client.Request.{CreateRoom, Messages}
 
   @type t :: %__MODULE__{
@@ -22,7 +22,7 @@ defmodule Architex.Room do
     has_many :aliases, Alias, foreign_key: :room_id
   end
 
-  @spec changeset(Room.t(), map()) :: Ecto.Changeset.t()
+  @spec changeset(%Room{}, map()) :: Ecto.Changeset.t()
   def changeset(room, params \\ %{}) do
     cast(room, params, [:visibility])
   end
diff --git a/lib/architex_web/client/controllers/room_controller.ex b/lib/architex_web/client/controllers/room_controller.ex
index c330bdd..68ec9b2 100644
--- a/lib/architex_web/client/controllers/room_controller.ex
+++ b/lib/architex_web/client/controllers/room_controller.ex
@@ -229,11 +229,7 @@ defmodule ArchitexWeb.Client.RoomController do
     end
   end
 
-  # GET /_matrix/client/r0/rooms/!atYDsyowueiToUvuqY:localhost:4000/messages
-  # Parameters: %{"dir" => "b", "from" => "", "limit" => "727", "path" => ["_matrix", "client", "r0", "rooms", "!atYDsyowueiToUvuqY:localhost:4000", "messages"]}
   def messages(%Conn{assigns: %{account: account}} = conn, %{"room_id" => room_id} = params) do
-    # IO.inspect(Messages.changeset(%Messages{}, params))
-
     with {:ok, request} <- Messages.parse(params) do
       room_query =
         account
diff --git a/lib/architex_web/client/request/create_room.ex b/lib/architex_web/client/request/create_room.ex
index 33d507e..3d7d78f 100644
--- a/lib/architex_web/client/request/create_room.ex
+++ b/lib/architex_web/client/request/create_room.ex
@@ -6,13 +6,13 @@ defmodule ArchitexWeb.Client.Request.CreateRoom do
   alias Ecto.Changeset
 
   @type t :: %__MODULE__{
-          visibility: String.t(),
-          room_alias_name: String.t(),
-          name: String.t(),
-          topic: String.t(),
-          invite: list(String.t()),
-          room_version: String.t(),
-          preset: String.t()
+          visibility: String.t() | nil,
+          room_alias_name: String.t() | nil,
+          name: String.t() | nil,
+          topic: String.t() | nil,
+          invite: list(String.t()) | nil,
+          room_version: String.t() | nil,
+          preset: String.t() | nil
         }
 
   @primary_key false
diff --git a/lib/architex_web/federation/controllers/event_controller.ex b/lib/architex_web/federation/controllers/event_controller.ex
index 6c048ed..151e932 100644
--- a/lib/architex_web/federation/controllers/event_controller.ex
+++ b/lib/architex_web/federation/controllers/event_controller.ex
@@ -90,16 +90,23 @@ defmodule ArchitexWeb.Federation.EventController do
         case RoomServer.get_room_server(room) do
           {:ok, pid} ->
             if RoomServer.server_in_room?(pid, origin) do
-              {state_events, auth_chain} =
+              # {state_events, auth_chain} =
+              data =
                 case state_or_state_ids do
-                  :state -> RoomServer.get_state_at_event(pid, event)
-                  :state_ids -> RoomServer.get_state_ids_at_event(pid, event)
-                end
+                  :state ->
+                    {state_events, auth_chain} = RoomServer.get_state_at_event(pid, event)
 
-              data = %{
-                auth_chain: auth_chain,
-                pdus: state_events
-              }
+                    %{
+                      auth_chain: Enum.map(auth_chain, &Architex.Event.Formatters.as_pdu/1),
+                      pdus: Enum.map(state_events, &Architex.Event.Formatters.as_pdu/1)
+                    }
+
+                  :state_ids ->
+                    {state_event_ids, auth_chain_ids} =
+                      RoomServer.get_state_ids_at_event(pid, event)
+
+                    %{auth_chain: auth_chain_ids, pdus: state_event_ids}
+                end
 
               conn
               |> put_status(200)
diff --git a/lib/architex_web/federation/transaction.ex b/lib/architex_web/federation/transaction.ex
index 1826479..0366ebd 100644
--- a/lib/architex_web/federation/transaction.ex
+++ b/lib/architex_web/federation/transaction.ex
@@ -8,7 +8,7 @@ defmodule ArchitexWeb.Federation.Transaction do
   @type t :: %__MODULE__{
           origin: String.t(),
           origin_server_ts: integer(),
-          pdus: [Event.t()],
+          pdus: [map()],
           edus: [edu()] | nil
         }
 
@@ -29,7 +29,7 @@ defmodule ArchitexWeb.Federation.Transaction do
     %Transaction{
       origin: Architex.server_name(),
       origin_server_ts: System.os_time(:millisecond),
-      pdus: Enum.map(pdu_events, &Architex.to_serializable_map/1),
+      pdus: Enum.map(pdu_events, &Architex.Event.Formatters.as_pdu/1),
       edus: edus
     }
   end
diff --git a/priv/repo/migrations/20210830160818_create_initial_tables.exs b/priv/repo/migrations/20210830160818_create_initial_tables.exs
index 5f28c00..f9848dd 100644
--- a/priv/repo/migrations/20210830160818_create_initial_tables.exs
+++ b/priv/repo/migrations/20210830160818_create_initial_tables.exs
@@ -27,19 +27,23 @@ defmodule Architex.Repo.Migrations.CreateInitialTables do
 
     create table(:events, primary_key: false) do
       add :nid, :serial, primary_key: true
-
-      add :origin_server_ts, :bigint, null: false
-      add :unsigned, :map, default: %{}, null: true
-      add :hashes, :map, null: false
-      add :signatures, :map, null: false
       add :id, :string, null: false
-      add :content, :map
-      add :type, :string, null: false
-      add :state_key, :string
-      add :sender, :string, null: false
-      add :prev_events, {:array, :string}, null: false
+
+      # PDU Fields
       add :auth_events, {:array, :string}, null: false
+      add :content, :map, null: false
+      add :depth, :integer, null: false
+      add :hashes, :map, null: false
+      add :origin, :string, null: false
+      add :origin_server_ts, :bigint, null: false
+      add :prev_events, {:array, :string}, null: false
+      add :redacts, :string, null: true
       add :room_id, references(:rooms, type: :string), null: false
+      add :sender, :string, null: false
+      add :signatures, :map, null: false
+      add :state_key, :string, null: true
+      add :type, :string, null: false
+      add :unsigned, :map, default: %{}, null: true
     end
 
     create index(:events, [:id], unique: true)
diff --git a/test/controllers/login_controller_test.exs b/test/controllers/login_controller_test.exs
index 4d2b1a7..59a8b30 100644
--- a/test/controllers/login_controller_test.exs
+++ b/test/controllers/login_controller_test.exs
@@ -40,7 +40,7 @@ defmodule ArchitexWeb.LoginControllerTest do
     test "handles unknown matrix user id", %{conn: conn} do
       conn = post_json(conn, Routes.login_path(Endpoint, :login), @basic_params)
 
-      assert %{"errcode" => "M_FORBIDDEN"} = json_response(conn, 400)
+      assert %{"errcode" => "M_FORBIDDEN"} = json_response(conn, 403)
     end
 
     test "handles wrong password", %{conn: conn} do
@@ -48,7 +48,7 @@ defmodule ArchitexWeb.LoginControllerTest do
 
       conn = post_json(conn, Routes.login_path(Endpoint, :login), @basic_params)
 
-      assert %{"errcode" => "M_FORBIDDEN"} = json_response(conn, 400)
+      assert %{"errcode" => "M_FORBIDDEN"} = json_response(conn, 403)
     end
 
     # TODO: Test display name