diff --git a/.github/ISSUE_TEMPLATE/proposal.md b/.github/ISSUE_TEMPLATE/proposal.md
index f347dcb..32d6ec3 100644
--- a/.github/ISSUE_TEMPLATE/proposal.md
+++ b/.github/ISSUE_TEMPLATE/proposal.md
@@ -1,10 +1,9 @@
 ---
 name: Proposal
 about: Suggest an idea for this project
-title: ''
+title: ""
 labels: enhancement, needs review
-assignees: ''
-
+assignees: ""
 ---
 
 **Is your feature request related to a problem? Please describe.**
@@ -29,7 +28,7 @@ For example
 Or
 
 ```elixir
-  Api.read(:resource, bar: 10) # <- Adding `bar` here would cause <x>
+  Ash.read(..., bar: 10) # <- Adding `bar` here would cause <x>
 ```
 
 **Additional context**
diff --git a/.tool-versions b/.tool-versions
deleted file mode 100644
index 38d92fa..0000000
--- a/.tool-versions
+++ /dev/null
@@ -1,2 +0,0 @@
-erlang 26.0.2
-elixir 1.15.4-otp-26
diff --git a/lib/data_layer/data_layer.ex b/lib/data_layer/data_layer.ex
index 03e097f..9ef71ac 100644
--- a/lib/data_layer/data_layer.ex
+++ b/lib/data_layer/data_layer.ex
@@ -133,7 +133,7 @@ defmodule AshJsonApiWrapper.DataLayer do
   defmodule Query do
     @moduledoc false
     defstruct [
-      :api,
+      :domain,
       :context,
       :headers,
       :action,
@@ -206,8 +206,8 @@ defmodule AshJsonApiWrapper.DataLayer do
   def can?(_, _), do: false
 
   @impl true
-  def resource_to_query(resource, api \\ nil) do
-    %Query{path: AshJsonApiWrapper.DataLayer.Info.endpoint_base(resource), api: api}
+  def resource_to_query(resource, domain \\ nil) do
+    %Query{path: AshJsonApiWrapper.DataLayer.Info.endpoint_base(resource), domain: domain}
   end
 
   @impl true
@@ -341,7 +341,7 @@ defmodule AshJsonApiWrapper.DataLayer do
        query
        | query_params: params,
          headers: headers,
-         api: query.api,
+         domain: query.domain,
          action: action,
          endpoint: AshJsonApiWrapper.DataLayer.Info.endpoint(resource, action.name),
          context: context
@@ -667,7 +667,7 @@ defmodule AshJsonApiWrapper.DataLayer do
     if is_nil(query.runtime_filter) do
       {:ok, results}
     else
-      Ash.Filter.Runtime.filter_matches(query.api, results, query.runtime_filter)
+      Ash.Filter.Runtime.filter_matches(query.domain, results, query.runtime_filter)
     end
   end
 
diff --git a/lib/errors/invalid_data.ex b/lib/errors/invalid_data.ex
index 13372c1..ea5c27e 100644
--- a/lib/errors/invalid_data.ex
+++ b/lib/errors/invalid_data.ex
@@ -1,19 +1,12 @@
 defmodule AshJsonApiWrapper.Errors.InvalidData do
   @moduledoc "Used when an invalid value is present in the response for a given attribute"
-  use Ash.Error.Exception
 
-  def_ash_error([:field, :value], class: :invalid)
+  use Splode.Error, fields: [:field, :value], class: :invalid
 
-  defimpl Ash.ErrorKind do
-    def id(_), do: Ash.UUID.generate()
-
-    def code(_), do: "invalid_data"
-
-    def message(error) do
-      "Invalid value provided#{for_field(error)}: #{inspect(error.value)}"
-    end
-
-    defp for_field(%{field: field}) when not is_nil(field), do: " for #{field}"
-    defp for_field(_), do: ""
+  def message(error) do
+    "Invalid value provided#{for_field(error)}: #{inspect(error.value)}"
   end
+
+  defp for_field(%{field: field}) when not is_nil(field), do: " for #{field}"
+  defp for_field(_), do: ""
 end
diff --git a/lib/open_api/resource_generator.ex b/lib/open_api/resource_generator.ex
index f90fe24..5ff00da 100644
--- a/lib/open_api/resource_generator.ex
+++ b/lib/open_api/resource_generator.ex
@@ -2,7 +2,7 @@ defmodule AshJsonApiWrapper.OpenApi.ResourceGenerator do
   @moduledoc "Generates resources from an open api specification"
 
   # sobelow_skip ["DOS.StringToAtom"]
-  def generate(json, main_config) do
+  def generate(json, domain, main_config) do
     main_config[:resources]
     |> Enum.map(fn {resource, config} ->
       endpoints =
@@ -158,7 +158,7 @@ defmodule AshJsonApiWrapper.OpenApi.ResourceGenerator do
       code =
         """
         defmodule #{resource} do
-          use Ash.Resource, data_layer: AshJsonApiWrapper.DataLayer
+          use Ash.Resource, domain: #{inspect(domain)}, data_layer: AshJsonApiWrapper.DataLayer
 
           json_api_wrapper do
             #{tesla}
diff --git a/test/custom_pagination_test.exs b/test/custom_pagination_test.exs
index a888273..3725d6c 100644
--- a/test/custom_pagination_test.exs
+++ b/test/custom_pagination_test.exs
@@ -72,8 +72,9 @@ defmodule AshJsonApiWrapper.CustomPagination.Test do
 
   defmodule Users do
     use Ash.Resource,
+      domain: AshJsonApiWrapper.CustomPagination.Test.Domain,
       data_layer: AshJsonApiWrapper.DataLayer,
-      validate_api_inclusion?: false
+      validate_domain_inclusion?: false
 
     json_api_wrapper do
       tesla(TestingTesla)
@@ -112,8 +113,8 @@ defmodule AshJsonApiWrapper.CustomPagination.Test do
     end
   end
 
-  defmodule Api do
-    use Ash.Api, validate_config_inclusion?: false
+  defmodule Domain do
+    use Ash.Domain, validate_config_inclusion?: false
 
     resources do
       allow_unregistered?(true)
@@ -160,12 +161,12 @@ defmodule AshJsonApiWrapper.CustomPagination.Test do
       Users
       |> Ash.Query.for_read(:list_users)
       # |> Ash.Query.limit(2)
-      |> Api.read!(page: [limit: 2, offset: 0])
+      |> Ash.read!(page: [limit: 2, offset: 0])
 
     users2 =
       Users
       |> Ash.Query.for_read(:list_users)
-      |> Api.read!(page: [limit: 2, offset: 1])
+      |> Ash.read!(page: [limit: 2, offset: 1])
 
     users_count = users.results |> Enum.count()
     users2_count = users2.results |> Enum.count()
diff --git a/test/hackernews_test.exs b/test/hackernews_test.exs
index 60bca73..86ec8dc 100644
--- a/test/hackernews_test.exs
+++ b/test/hackernews_test.exs
@@ -6,8 +6,9 @@ defmodule AshJsonApiWrapper.Hackernews.Test do
   defmodule TopStory do
     @moduledoc false
     use Ash.Resource,
+      domain: AshJsonApiWrapper.Hackernews.Test.Domain,
       data_layer: AshJsonApiWrapper.DataLayer,
-      validate_api_inclusion?: false
+      validate_domain_inclusion?: false
 
     json_api_wrapper do
       endpoints do
@@ -44,7 +45,7 @@ defmodule AshJsonApiWrapper.Hackernews.Test do
 
   defmodule ShortUrl do
     @moduledoc false
-    use Ash.Calculation
+    use Ash.Resource.Calculation
 
     def calculate(records, _, _) do
       Enum.map(records, fn record ->
@@ -60,8 +61,9 @@ defmodule AshJsonApiWrapper.Hackernews.Test do
   defmodule Story do
     @moduledoc false
     use Ash.Resource,
+      domain: AshJsonApiWrapper.Hackernews.Test.Domain,
       data_layer: AshJsonApiWrapper.DataLayer,
-      validate_api_inclusion?: false
+      validate_domain_inclusion?: false
 
     calculations do
       calculate(:short_url, :string, ShortUrl)
@@ -112,8 +114,9 @@ defmodule AshJsonApiWrapper.Hackernews.Test do
   defmodule User do
     @moduledoc false
     use Ash.Resource,
+      domain: AshJsonApiWrapper.Hackernews.Test.Domain,
       data_layer: AshJsonApiWrapper.DataLayer,
-      validate_api_inclusion?: false
+      validate_domain_inclusion?: false
 
     attributes do
       attribute :id, :string do
@@ -143,9 +146,9 @@ defmodule AshJsonApiWrapper.Hackernews.Test do
     end
   end
 
-  defmodule Api do
+  defmodule Domain do
     @moduledoc false
-    use Ash.Api, validate_config_inclusion?: false
+    use Ash.Domain, validate_config_inclusion?: false
 
     resources do
       allow_unregistered?(true)
@@ -157,7 +160,7 @@ defmodule AshJsonApiWrapper.Hackernews.Test do
              TopStory
              |> Ash.Query.limit(1)
              |> Ash.Query.load(story: :user)
-             |> Api.read!()
+             |> Domain.read!()
              |> Enum.map(& &1.story)
 
     assert is_binary(top_story.url)
diff --git a/test/open_api_cybrid_test.exs b/test/open_api_cybrid_test.exs
index aec23ab..ec03b98 100644
--- a/test/open_api_cybrid_test.exs
+++ b/test/open_api_cybrid_test.exs
@@ -38,9 +38,18 @@ defmodule AshJsonApiWrapper.OpenApi.CybridTest do
     ]
   ]
 
+  defmodule Domain do
+    use Ash.Domain,
+      validate_config_inclusion?: false
+
+    resources do
+      allow_unregistered? true
+    end
+  end
+
   test "it does stuff" do
     @json
-    |> AshJsonApiWrapper.OpenApi.ResourceGenerator.generate(@config)
+    |> AshJsonApiWrapper.OpenApi.ResourceGenerator.generate(Domain, @config)
     |> Enum.map(fn {resource, code} ->
       Code.eval_string(code)
       resource
diff --git a/test/open_api_petstore_test.exs b/test/open_api_petstore_test.exs
index ecea4e9..581bd89 100644
--- a/test/open_api_petstore_test.exs
+++ b/test/open_api_petstore_test.exs
@@ -31,9 +31,18 @@ defmodule AshJsonApiWrapper.OpenApi.PetstoreTest do
     ]
   ]
 
+  defmodule Domain do
+    use Ash.Domain,
+      validate_config_inclusion?: false
+
+    resources do
+      allow_unregistered? true
+    end
+  end
+
   test "it does stuff" do
     @json
-    |> AshJsonApiWrapper.OpenApi.ResourceGenerator.generate(@config)
+    |> AshJsonApiWrapper.OpenApi.ResourceGenerator.generate(Domain, @config)
     |> Enum.map(fn {resource, code} ->
       Code.eval_string(code)
       resource
diff --git a/test/petstore_test.exs b/test/petstore_test.exs
index aadb895..2ef4827 100644
--- a/test/petstore_test.exs
+++ b/test/petstore_test.exs
@@ -11,7 +11,8 @@ defmodule AshJsonApiWrapper.Petstore.Test do
   defmodule Petstore do
     use Ash.Resource,
       data_layer: AshJsonApiWrapper.DataLayer,
-      validate_api_inclusion?: false
+      domain: AshJsonApiWrapper.Petstore.Test.Domain,
+      validate_domain_inclusion?: false
 
     json_api_wrapper do
       tesla(TestingTesla)
@@ -68,8 +69,8 @@ defmodule AshJsonApiWrapper.Petstore.Test do
     end
   end
 
-  defmodule Api do
-    use Ash.Api, validate_config_inclusion?: false
+  defmodule Domain do
+    use Ash.Domain, validate_config_inclusion?: false
 
     resources do
       allow_unregistered?(true)
@@ -80,16 +81,16 @@ defmodule AshJsonApiWrapper.Petstore.Test do
     Petstore
     |> Ash.Query.for_read(:find_pets_by_status)
     |> Ash.Query.filter(status == "pending")
-    |> Api.read!()
+    |> Ash.read!()
 
     Petstore
     |> Ash.Query.for_read(:by_status)
     |> Ash.Query.filter(status == "available")
-    |> Api.read!()
+    |> Ash.read!()
 
     Petstore
     |> Ash.Query.for_read(:pet)
     |> Ash.Query.filter(id == 10)
-    |> Api.read!()
+    |> Ash.read!()
   end
 end