diff --git a/apps/one_piece_ecto/.formatter.exs b/apps/one_piece_ecto/.formatter.exs
new file mode 100644
index 0000000..86d2bdb
--- /dev/null
+++ b/apps/one_piece_ecto/.formatter.exs
@@ -0,0 +1,5 @@
+[
+  line_length: 120,
+  import_deps: [:ecto],
+  inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"]
+]
diff --git a/apps/one_piece_ecto/.gitignore b/apps/one_piece_ecto/.gitignore
new file mode 100644
index 0000000..4459deb
--- /dev/null
+++ b/apps/one_piece_ecto/.gitignore
@@ -0,0 +1,26 @@
+# The directory Mix will write compiled artifacts to.
+/_build/
+
+# If you run "mix test --cover", coverage assets end up here.
+/cover/
+
+# The directory Mix downloads your dependencies sources to.
+/deps/
+
+# Where third-party dependencies like ExDoc output generated docs.
+/doc/
+
+# Ignore .fetch files in case you like to edit your project deps locally.
+/.fetch
+
+# If the VM crashes, it generates a dump, let's ignore it too.
+erl_crash.dump
+
+# Also ignore archive artifacts (built via "mix archive.build").
+*.ez
+
+# Ignore package tarball (built via "mix hex.build").
+one_piece_ecto-*.tar
+
+# Temporary files, for example, from tests.
+/tmp/
diff --git a/apps/one_piece_ecto/README.md b/apps/one_piece_ecto/README.md
new file mode 100644
index 0000000..77a801a
--- /dev/null
+++ b/apps/one_piece_ecto/README.md
@@ -0,0 +1,21 @@
+# OnePieceEcto
+
+**TODO: Add description**
+
+## Installation
+
+If [available in Hex](https://hex.pm/docs/publish), the package can be installed
+by adding `one_piece_ecto` to your list of dependencies in `mix.exs`:
+
+```elixir
+def deps do
+  [
+    {:one_piece_ecto, "~> 0.1.0"}
+  ]
+end
+```
+
+Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
+and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
+be found at <https://hexdocs.pm/one_piece_ecto>.
+
diff --git a/apps/one_piece_ecto/lib/one_piece/ecto/schema.ex b/apps/one_piece_ecto/lib/one_piece/ecto/schema.ex
new file mode 100644
index 0000000..753d3c1
--- /dev/null
+++ b/apps/one_piece_ecto/lib/one_piece/ecto/schema.ex
@@ -0,0 +1,153 @@
+defmodule OnePiece.Ecto.Schema do
+  @moduledoc """
+  Extends a `Ecto.Schema` module with functionality.
+  """
+
+  alias Ecto.Changeset
+
+  @doc """
+  Extends a `Ecto.Schema` module with some functionality.
+
+      defmodule MySchema do
+        use Ecto.Schema
+        use OnePiece.Ecto.Schema
+
+        embedded_schema do
+          field :title, :string
+          # ...
+        end
+      end
+
+  The following functions are available in the module now:
+
+  `new/1`: **overridable** struct factory function. It takes an attribute map
+  and runs the `changeset/2`.
+
+  `new!/1`: **overridable** like `new/1` raising an error when the validation
+  fails.
+
+  `changeset/2`: **overridable** function. It takes a struct and the attributes
+  and returns a `Ecto.Changeset`.
+  The default implementation apply a deeply-nested casting over all the fields
+  using `Ecto.Changeset.cast/4` and `Ecto.Changeset.cast_embed/4`.
+  When `@enforce_keys` is defined, it will apply `Ecto.Changeset.validate_required/3`
+  to the list of fields.
+  When overriding the function, allows you have full control over the validation
+  layer, deactivating all the nested-casting.
+  """
+  @spec __using__(opts :: []) :: any()
+  defmacro __using__(_opts \\ []) do
+    quote do
+      @before_compile OnePiece.Ecto.Schema
+
+      @doc """
+      Creates a `t:t/0`.
+      """
+      @spec new(attrs :: map()) :: {:ok, %__MODULE__{}}
+      def new(attrs) do
+        OnePiece.Ecto.Schema.__new__(__MODULE__, attrs)
+      end
+
+      @doc """
+      Creates a `t:t/0`.
+      """
+      @spec new!(attrs :: map()) :: %__MODULE__{}
+      def new!(attrs) do
+        OnePiece.Ecto.Schema.__new__!(__MODULE__, attrs)
+      end
+
+      @doc """
+      Returns an `t:Ecto.Changeset.t/0` for a given `t:t/0` model.
+      """
+      @spec changeset(model :: %__MODULE__{}, attrs :: map()) :: Ecto.Changeset.t()
+      def changeset(model, attrs) do
+        OnePiece.Ecto.Schema.__changeset__(model, attrs)
+      end
+
+      defoverridable new: 1, new!: 1, changeset: 2
+    end
+  end
+
+  defmacro __before_compile__(env) do
+    enforced_keys = get_enforced_keys(env)
+
+    quote unquote: false, bind_quoted: [enforced_keys: enforced_keys] do
+      def __enforced_keys__ do
+        unquote(enforced_keys)
+      end
+
+      for the_key <- enforced_keys do
+        def __enforced_keys__?(unquote(the_key)) do
+          true
+        end
+      end
+
+      def __enforced_keys__?(_) do
+        false
+      end
+    end
+  end
+
+  defp get_enforced_keys(env) do
+    enforce_keys = Module.get_attribute(env.module, :enforce_keys) || []
+    enforce_keys ++ get_primary_key_name(env)
+  end
+
+  defp get_primary_key_name(env) do
+    case Module.get_attribute(env.module, :primary_key) do
+      {field_name, _, _} -> [field_name]
+      _ -> []
+    end
+  end
+
+  def __new__(struct_module, attrs) do
+    struct_module
+    |> apply_changeset(attrs)
+    |> Changeset.apply_action(:new)
+  end
+
+  def __new__!(struct_module, attrs) do
+    struct_module
+    |> apply_changeset(attrs)
+    |> Changeset.apply_action!(:new!)
+  end
+
+  def __changeset__(%struct_module{} = model, attrs) do
+    embeds = struct_module.__schema__(:embeds)
+    fields = struct_module.__schema__(:fields)
+
+    changeset =
+      message
+      |> Changeset.cast(attrs, fields -- embeds)
+      |> Changeset.validate_required(struct_module.__enforced_keys__() -- embeds)
+
+    Enum.reduce(
+      embeds,
+      changeset,
+      &cast_embed(&1, &2, struct_module, attrs)
+    )
+  end
+
+  defp cast_embed(field, changeset, struct_module, attrs) do
+    case is_struct(attrs[field]) do
+      false ->
+        Changeset.cast_embed(changeset, field, required: struct_module.__enforced_keys__?(field))
+
+      true ->
+        # credo:disable-for-next-line Credo.Check.Design.TagTODO
+        # TODO: Validate that the struct is of the correct type.
+        #   It may be the case that you passed a completely different struct as the value. We could `cast_embed`
+        #   always and fix the `Changeset.cast(attrs, fields -- embeds)` by converting the `attrs` into a map. But it
+        #   would be a bit more expensive since it will run the casting for a field that was already casted.
+        #   Checking the struct types MAY be enough but taking into consideration `embeds_many` could complicated
+        #   things. For now, we'll just assume that the user knows what they're doing.
+        Changeset.put_change(changeset, field, attrs[field])
+    end
+  end
+
+  defp apply_changeset(struct_module, attrs) do
+    struct_module
+    |> struct()
+    |> struct_module.changeset(attrs)
+  end
+end
diff --git a/apps/one_piece_ecto/mix.exs b/apps/one_piece_ecto/mix.exs
new file mode 100644
index 0000000..a7278d2
--- /dev/null
+++ b/apps/one_piece_ecto/mix.exs
@@ -0,0 +1,110 @@
+defmodule OnePiece.Ecto.MixProject do
+  use Mix.Project
+
+  @app :one_piece_ecto
+  @version "0.1.0"
+  @elixir_version "~> 1.13"
+  @source_url "https://github.com/straw-hat-team/beam-monorepo"
+
+  def project do
+    [
+      build_path: "../../_build",
+      config_path: "../../config/config.exs",
+      deps_path: "../../deps",
+      lockfile: "../../mix.lock",
+      name: "OnePiece.Ecto",
+      description: "Extend Ecto package",
+      app: @app,
+      version: @version,
+      elixir: @elixir_version,
+      elixir: "~> 1.14",
+      start_permanent: Mix.env() == :prod,
+      deps: deps(),
+      aliases: aliases(),
+      test_coverage: test_coverage(),
+      preferred_cli_env: preferred_cli_env(),
+      package: package(),
+      docs: docs(),
+      dialyzer: dialyzer()
+    ]
+  end
+
+  def application do
+    [
+      extra_applications: [:logger]
+    ]
+  end
+
+  defp deps do
+    [
+      {:ecto, "~> 3.6"},
+
+      # Tools
+      {:dialyxir, ">= 0.0.0", only: [:dev], runtime: false},
+      {:credo, ">= 0.0.0", only: [:dev, :test], runtime: false},
+      {:excoveralls, ">= 0.0.0", only: [:test], runtime: false},
+      {:ex_doc, ">= 0.0.0", only: [:dev], runtime: false}
+    ]
+  end
+
+  defp aliases do
+    [
+      test: ["test --trace"]
+    ]
+  end
+
+  defp test_coverage do
+    [tool: ExCoveralls]
+  end
+
+  defp preferred_cli_env do
+    [
+      "coveralls.html": :test,
+      "coveralls.json": :test,
+      coveralls: :test
+    ]
+  end
+
+  defp dialyzer do
+    [
+      plt_core_path: "priv/plts",
+      ignore_warnings: ".dialyzer_ignore.exs"
+    ]
+  end
+
+  defp package do
+    [
+      name: @app,
+      files: [
+        ".formatter.exs",
+        "lib",
+        "mix.exs",
+        "README*",
+        "LICENSE*"
+      ],
+      maintainers: ["Yordis Prieto"],
+      licenses: ["MIT"],
+      links: %{
+        "GitHub" => @source_url
+      }
+    ]
+  end
+
+  defp docs do
+    [
+      main: "readme",
+      homepage_url: @source_url,
+      source_url_pattern: "#{@source_url}/blob/#{@app}@v#{@version}/apps/#{@app}/%{path}#L%{line}",
+      skip_undefined_reference_warnings_on: ["CHANGELOG.md"],
+      extras: [
+        "README.md",
+        "CHANGELOG.md"
+      ],
+      groups_for_extras: [
+        "How-to": ~r/docs\/how-to\/.?/,
+        Explanations: ~r/docs\/explanations\/.?/,
+        References: ~r/docs\/references\/.?/
+      ]
+    ]
+  end
+end
diff --git a/apps/one_piece_ecto/priv/plts/.gitkeep b/apps/one_piece_ecto/priv/plts/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/apps/one_piece_ecto/test/one_piece/ecto/schema_test.exs b/apps/one_piece_ecto/test/one_piece/ecto/schema_test.exs
new file mode 100644
index 0000000..a3d54a7
--- /dev/null
+++ b/apps/one_piece_ecto/test/one_piece/ecto/schema_test.exs
@@ -0,0 +1,42 @@
+defmodule OnePiece.Ecto.SchemaTest do
+  use ExUnit.Case, async: true
+
+  describe "new/1" do
+    test "creates a struct" do
+      assert {:ok, %TestSupport.MessageOne{title: nil}} = TestSupport.MessageOne.new(%{})
+    end
+
+    test "validates a key enforce" do
+      {:error, changeset} = TestSupport.MessageTwo.new(%{})
+      assert %{title: ["can't be blank"]} = TestSupport.errors_on(changeset)
+    end
+
+    test "validates a key enforce for embed fields" do
+      {:error, changeset} = TestSupport.MessageThree.new(%{})
+      assert %{target: ["can't be blank"]} = TestSupport.errors_on(changeset)
+    end
+
+    test "validates casting embed fields" do
+      assert {:ok, %TestSupport.MessageThree{target: %TestSupport.MessageOne{title: "Hello, World!"}}} =
+               TestSupport.MessageThree.new(%{target: %{title: "Hello, World!"}})
+    end
+
+    test "bypass casting structs" do
+      assert {:ok, %TestSupport.MessageThree{target: %TestSupport.MessageOne{title: "Hello, World!"}}} =
+               TestSupport.MessageThree.new(%{target: %TestSupport.MessageOne{title: "Hello, World!"}})
+    end
+
+    test "validates casting embed fields with a wrong value" do
+      {:error, changeset} = TestSupport.MessageThree.new(%{target: "a wrong value"})
+      assert %{target: ["is invalid"]} = TestSupport.errors_on(changeset)
+    end
+  end
+
+  describe "new!/1" do
+    test "raises an error when a validation fails" do
+      assert_raise Ecto.InvalidChangesetError, fn ->
+        TestSupport.MessageTwo.new!(%{})
+      end
+    end
+  end
+end
diff --git a/apps/one_piece_ecto/test/support/messages.ex b/apps/one_piece_ecto/test/support/messages.ex
new file mode 100644
index 0000000..f672171
--- /dev/null
+++ b/apps/one_piece_ecto/test/support/messages.ex
@@ -0,0 +1,82 @@
+defmodule TestSupport do
+  @moduledoc false
+
+  defmodule MessageOne do
+    @moduledoc false
+
+    use Ecto.Schema
+    use OnePiece.Commanded.ValueObject
+
+    embedded_schema do
+      field :title, :string
+    end
+  end
+
+  defmodule MessageTwo do
+    @moduledoc false
+
+    use Ecto.Schema
+    use OnePiece.Commanded.ValueObject
+
+    @enforce_keys [:title]
+    embedded_schema do
+      field :title, :string
+    end
+  end
+
+  defmodule MessageThree do
+    @moduledoc false
+
+    use Ecto.Schema
+    use OnePiece.Commanded.ValueObject
+
+    @enforce_keys [:target]
+    embedded_schema do
+      embeds_one(:target, MessageOne)
+    end
+  end
+
+  defmodule MyEntityOne do
+    @moduledoc false
+
+    use OnePiece.Commanded.Entity, identifier: :uuid
+
+    @enforce_keys [:name]
+    embedded_schema do
+      field :name, :string
+    end
+  end
+
+  defmodule MyCommandOne do
+    @moduledoc false
+
+    use Ecto.Schema, aggregate_identifier: :uuid
+
+    embedded_schema do
+    end
+  end
+
+  defmodule MyEventOne do
+    @moduledoc false
+
+    use Ecto.Schema
+
+    @primary_key {:uuid, :string, autogenerate: false}
+
+    embedded_schema do
+      field :name, :string
+    end
+  end
+
+  defmodule MyEventTwo do
+    @moduledoc false
+
+    use Ecto.Schema, aggregate_identifier: :uuid
+
+    @primary_key {:uuid, :string, autogenerate: false}
+
+    embedded_schema do
+      field :name, :string
+    end
+  end
+end
diff --git a/apps/one_piece_ecto/test/test_helper.exs b/apps/one_piece_ecto/test/test_helper.exs
new file mode 100644
index 0000000..869559e
--- /dev/null
+++ b/apps/one_piece_ecto/test/test_helper.exs
@@ -0,0 +1 @@
+ExUnit.start()