   end
 
   def put_published_at(changeset) do
-    put_change(changeset, :published_at, Ecto.DateTime.local)
-    |> put_change(:published, true)
+    change(changeset, 
+      %{published_at: Ecto.DateTime.local, published: true})
   end
 
   def inflate_tags(changeset) do

  end

  @required_fields ~w(title)
  @optional_fields ~w(body permalink tags summary published_at)

  after_load :flat_tags


    field :body, :string
    field :permalink, :string
    field :tags, {:array, :string}
    field :published, :boolean, default: false
    field :published_at, Ecto.DateTime
    field :tags_text, :string, virtual: true

