diff --git a/jsonapi-rails.gemspec b/jsonapi-rails.gemspec
index 656a00b..3a38e72 100644
--- a/jsonapi-rails.gemspec
+++ b/jsonapi-rails.gemspec
@@ -20,5 +20,4 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'sqlite3'
   spec.add_development_dependency 'rake',        '~> 11.3'
   spec.add_development_dependency 'rspec-rails', '~> 3.5'
-  spec.add_development_dependency 'dry-validation', '~> 0.10'
 end
diff --git a/lib/jsonapi/rails/action_controller.rb b/lib/jsonapi/rails/action_controller.rb
index d3b1aab..856e2de 100644
--- a/lib/jsonapi/rails/action_controller.rb
+++ b/lib/jsonapi/rails/action_controller.rb
@@ -33,8 +33,6 @@ def _deserializable(key, options, fallback, &block)
         end
       end
 
-      private
-
       def jsonapi_pointers
         request.env[JSONAPI_POINTERS_KEY]
       end
diff --git a/spec/action_controller_spec.rb b/spec/action_controller_spec.rb
index bd608cd..7c3842f 100644
--- a/spec/action_controller_spec.rb
+++ b/spec/action_controller_spec.rb
@@ -1,17 +1,72 @@
 require 'rails_helper'
 
-RSpec.describe ActionController::Base do
-  it 'exposes the deserialization mapping via the jsonapi_pointers method' do
-    pointers = { id: '/data/id', type: '/data/type' }
-
-    allow(subject).to receive(:request) do
-      OpenStruct.new(
-        env: {
-          JSONAPI::Rails::ActionController::JSONAPI_POINTERS_KEY => pointers
+describe ActionController::Base, type: :controller do
+  describe '.deserializable_resource' do
+    controller do
+      deserializable_resource :user
+
+      def create
+        render plain: 'ok'
+      end
+    end
+
+    let(:payload) do
+      {
+        _jsonapi: {
+          'data' => {
+            'type' => 'users',
+            'attributes' => { 'foo' => 'bar', 'bar' => 'baz' }
+          }
+        }
+      }
+    end
+
+    it 'makes the deserialized resource available in params' do
+      post :create, params: payload
+
+      expected = { 'type' => 'users', 'foo' => 'bar', 'bar' => 'baz' }
+      expect(controller.params[:user]).to eq(expected)
+    end
+
+    it 'makes the deserialization mapping available via #jsonapi_pointers' do
+      post :create, params: payload
+
+      expected = { foo: '/data/attributes/foo',
+                   bar: '/data/attributes/bar',
+                   type: '/data/type' }
+      expect(controller.jsonapi_pointers).to eq(expected)
+    end
+  end
+
+  describe '#render jsonapi:' do
+    controller do
+      def index
+        serializer = Class.new(JSONAPI::Serializable::Resource) do
+          type :users
+          attribute :name
+        end
+        user = OpenStruct.new(id: 1, name: 'Lucas')
+
+        render jsonapi: user, class: serializer
+      end
+    end
+
+    subject { JSON.parse(response.body) }
+    let(:serialized_user) do
+      {
+        'data' => {
+          'id' => '1',
+          'type' => 'users',
+          'attributes' => { 'name' => 'Lucas' }
         }
-      )
+      }
     end
 
-    expect(subject.send(:jsonapi_pointers)).to equal pointers
+    it 'renders a JSON API document' do
+      get :index
+
+      expect(response.content_type).to eq('application/vnd.api+json')
+      is_expected.to eq(serialized_user)
+    end
   end
 end
diff --git a/spec/dummy/app/controllers/tweets_controller.rb b/spec/dummy/app/controllers/tweets_controller.rb
deleted file mode 100644
index 4b1c381..0000000
--- a/spec/dummy/app/controllers/tweets_controller.rb
+++ /dev/null
@@ -1,49 +0,0 @@
-class TweetsController < ActionController::Base
-  deserializable_resource :tweet, only: [:create, :update]
-
-  def index
-    tweets = Tweet.all
-
-    render jsonapi: tweets,
-           jsonapi_object: { version: '1.0' },
-           meta: { foo: 'bar' },
-           links: {
-             self: 'http://foo.bar'
-           }
-  end
-
-  def show
-    tweet = Tweet.find(params[:id])
-
-    render jsonapi: tweet
-  end
-
-  def create
-    tweet = Tweet.new(create_params.merge(author: current_user))
-
-    p request.env['jsonapi_deserializable.reverse_mapping']
-
-    unless tweet.save
-      render jsonapi_errors: tweet.errors
-      return
-    end
-
-    render jsonapi: tweet, status: :created
-  end
-
-  def destroy
-    Tweet.delete(params[:id])
-
-    head :no_content
-  end
-
-  private
-
-  def current_user
-    User.first || User.create(name: 'Lucas', email: 'lucas@jsonapi-rb.org')
-  end
-
-  def create_params
-    params.require(:tweet).permit(:content, :parent_id)
-  end
-end
diff --git a/spec/dummy/app/deserializable/deserializable_tweet.rb b/spec/dummy/app/deserializable/deserializable_tweet.rb
deleted file mode 100644
index 99d5972..0000000
--- a/spec/dummy/app/deserializable/deserializable_tweet.rb
+++ /dev/null
@@ -1,13 +0,0 @@
-class DeserializableTweet < JSONAPI::Deserializable::Resource
-  id
-
-  attribute :content
-
-  has_one :parent do |rel, id, type|
-    field parent_id: id
-  end
-
-  has_one :author do |rel, id, type|
-    field author_id: id
-  end
-end
diff --git a/spec/dummy/app/models/tweet.rb b/spec/dummy/app/models/tweet.rb
deleted file mode 100644
index 90a76c2..0000000
--- a/spec/dummy/app/models/tweet.rb
+++ /dev/null
@@ -1,4 +0,0 @@
-class Tweet < ApplicationRecord
-  belongs_to :parent, optional: true
-  belongs_to :author, class_name: 'User'
-end
diff --git a/spec/dummy/app/models/user.rb b/spec/dummy/app/models/user.rb
deleted file mode 100644
index fef2809..0000000
--- a/spec/dummy/app/models/user.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-class User < ApplicationRecord
-  has_many :tweets
-end
diff --git a/spec/dummy/app/serializable/serializable_tweet.rb b/spec/dummy/app/serializable/serializable_tweet.rb
deleted file mode 100644
index e32465d..0000000
--- a/spec/dummy/app/serializable/serializable_tweet.rb
+++ /dev/null
@@ -1,9 +0,0 @@
-class SerializableTweet < JSONAPI::Serializable::Resource
-  type 'tweets'
-
-  attribute :content
-  attribute(:date) { @object.created_at }
-
-  has_one :parent
-  has_one :author
-end
diff --git a/spec/dummy/app/serializable/serializable_user.rb b/spec/dummy/app/serializable/serializable_user.rb
deleted file mode 100644
index 2a84a46..0000000
--- a/spec/dummy/app/serializable/serializable_user.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-class SerializableUser < JSONAPI::Serializable::Resource
-  type 'users'
-
-  attribute :name
-  attribute :email
-  attribute :created_at
-  attribute :updated_at
-
-  has_many :tweets
-end
diff --git a/spec/rails_helper.rb b/spec/rails_helper.rb
index 736d6e8..17e25b6 100644
--- a/spec/rails_helper.rb
+++ b/spec/rails_helper.rb
@@ -6,7 +6,6 @@
 require 'spec_helper'
 require 'rspec/rails'
 # Add additional requires below this line. Rails is not loaded until this point!
-require 'dry-validation'
 
 # Requires supporting ruby files with custom matchers and macros, etc, in
 # spec/support/ and its subdirectories. Files matching `spec/**/*_spec.rb` are
@@ -56,40 +55,3 @@
   # arbitrary gems may also be filtered via:
   # config.filter_gems_from_backtrace("gem name")
 end
-
-# Custom RSpec matchers
-module JSONAPI
-  module RSpec
-    class BeValidJsonapiMatcher
-      def matches?(body)
-        JSONAPI.parse_response!(JSON.parse(body))
-        true
-      end
-    end
-
-    def be_valid_jsonapi
-      BeValidJsonapiMatcher.new
-    end
-
-    class MatchSchemaMatcher
-      def matches?(body, &block)
-        schema = Dry::Validation.Schema(&block)
-        @body = JSON.parse(body) unless body.is_a?(Hash)
-        @result = schema.call(@body.with_indifferent_access)
-        @result.success?
-      end
-
-      def failure_message
-        "#{@body} #{@result.errors}"
-      end
-    end
-
-    def match_schema(&block)
-      MatchSchemaMatcher.new(&block)
-    end
-  end
-end
-
-RSpec.configure do |config|
-  config.include JSONAPI::RSpec
-end
diff --git a/spec/railtie_spec.rb b/spec/railtie_spec.rb
new file mode 100644
index 0000000..1b1879d
--- /dev/null
+++ b/spec/railtie_spec.rb
@@ -0,0 +1,11 @@
+require 'rails_helper'
+
+describe JSONAPI::Rails::Railtie do
+  it 'registers the JSON API MIME type' do
+    expect(Mime[:jsonapi]).to eq('application/vnd.api+json')
+  end
+
+  it 'registers the params parser for the JSON API MIME type' do
+    expect(::ActionDispatch::Request.parameter_parsers[:jsonapi]).not_to be_nil
+  end
+end
diff --git a/spec/requests/crud_spec.rb b/spec/requests/crud_spec.rb
deleted file mode 100644
index fb9a58b..0000000
--- a/spec/requests/crud_spec.rb
+++ /dev/null
@@ -1,99 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe 'Basic CRUD', type: :request do
-  let(:headers) do
-    { 'ACCEPT' => 'application/vnd.api+json' }
-  end
-
-  def body
-    JSON.parse(response.body)
-  end
-
-  it 'works' do
-    # Get empty tweets list
-    get '/tweets', headers: headers
-    expect(response).to be_success
-    expect(response).to have_http_status(200)
-    expect(response.body).to be_valid_jsonapi
-    expect(response.body).to match_schema do
-      required(:data).value(eql?: [])
-      required(:meta).value(eql?: { 'foo' => 'bar' })
-      required(:jsonapi).value(eql?: { 'version' => '1.0' })
-      required(:links).value(eql?: { 'self' => 'http://foo.bar' })
-    end
-
-    # Post first tweet
-    params = {
-      data: {
-        type: 'tweets',
-        attributes: {
-          content: 'foo'
-        },
-        relationships: {
-          author: {
-            data: {
-              id: 'foo',
-              type: 'bar'
-            }
-          }
-        }
-      }
-    }
-    post '/tweets',
-         params: params,
-         as: :json,
-         headers: headers.merge('CONTENT_TYPE' => 'application/vnd.api+json')
-    expect(response).to be_success
-    expect(response).to have_http_status(201)
-    expect(response.body).to be_valid_jsonapi
-    expect(response.body).to match_schema do
-      required(:data).schema do
-        required(:type).value(eql?: 'tweets')
-        required(:attributes).schema do
-          required(:content).value(eql?: 'foo')
-        end
-        required(:relationships).schema do
-          required(:author)
-        end
-      end
-    end
-    first_tweet = body
-
-    # Post second tweet
-    params = {
-      data: {
-        type: 'tweets',
-        attributes: {
-          content: 'foo'
-        }
-      }
-    }
-    post '/tweets',
-         params: params,
-         as: :json,
-         headers: headers.merge('CONTENT_TYPE' => 'application/vnd.api+json')
-    expect(response).to be_success
-    expect(response).to have_http_status(201)
-    expect { JSONAPI.parse_response!(body) }.not_to raise_error
-    second_tweet = body
-
-    # Get first tweet
-    get "/tweets/#{first_tweet['data']['id']}", headers: headers
-    expect(response).to be_success
-    expect(response).to have_http_status(200)
-    expect(response.body).to be_valid_jsonapi
-    expect(body).to eq(first_tweet)
-
-    # Delete first tweet
-    delete "/tweets/#{first_tweet['data']['id']}"
-    expect(response).to be_success
-    expect(response).to have_http_status(204)
-
-    # List remaining tweets
-    get '/tweets'
-    expect(response).to be_success
-    expect(response).to have_http_status(200)
-    expect(response.body).to be_valid_jsonapi
-    expect(body['data'].first).to eq(second_tweet['data'])
-  end
-end