diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8f29b7c..de16328 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1,7 +1,8 @@
 name: Tests
 
 on:
-  push
+  - push
+  - pull_request
 
 jobs:
   test:
@@ -9,11 +10,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [2.3, 2.7, '3.0']
-        graphql_version: ['1.9.19', '1.11.6']
-        exclude:
-          - graphql_version: '1.9.19'
-            ruby: '3.0'
+        ruby: [2.4, 2.7, '3.0']
+        graphql_version: ['~> 1.10.0', '~> 1.13']
     steps:
     - uses: actions/checkout@v2
     - uses: ruby/setup-ruby@v1
@@ -22,6 +20,4 @@ jobs:
         ruby-version: ${{ matrix.ruby }}
       env:
         GRAPHQL_VERSION: ${{ matrix.graphql_version }}
-        TESTING_LEGACY_DEFINITION_LAYER: ${{ startsWith(matrix.graphql_version, '1.9') }}
-    - run: bundle install
     - run: bundle exec rake
diff --git a/.rubocop.yml b/.rubocop.yml
index 34b2a82..8e0a2a5 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -5,6 +5,7 @@ inherit_from:
   - .rubocop_todo.yml
 
 AllCops:
+  SuggestExtensions: false
   TargetRubyVersion: 2.7
   Exclude:
     - vendor/**/*
diff --git a/README.md b/README.md
index 0b9917f..e142787 100644
--- a/README.md
+++ b/README.md
@@ -50,7 +50,7 @@ end
 
 Use `GraphQL::Batch` as a plugin in your schema _after_ specifying the mutation
 so that `GraphQL::Batch` can extend the mutation fields to clear the cache after
-they are resolved (for graphql >= `1.5.0`).
+they are resolved.
 
 ```ruby
 class MySchema < GraphQL::Schema
@@ -61,16 +61,6 @@ class MySchema < GraphQL::Schema
 end
 ```
 
-For pre `1.5.0` versions:
-
-```ruby
-MySchema = GraphQL::Schema.define do
-  query MyQueryType
-
-  GraphQL::Batch.use(self)
-end
-```
-
 #### Field Usage
 
 The loader class can be used from the resolver for a graphql field by calling `.for` with the grouping arguments to get a loader instance, then call `.load` on that instance with the key to load.
@@ -155,19 +145,19 @@ end
 ## Unit Testing
 
 Your loaders can be tested outside of a GraphQL query by doing the
-batch loads in a block passed to GraphQL::Batch.batch.  That method
+batch loads in a block passed to `GraphQL::Batch.batch`. That method
 will set up thread-local state to store the loaders, batch load any
 promise returned from the block then clear the thread-local state
 to avoid leaking state between tests.
 
 ```ruby
-  def test_single_query
-    product = products(:snowboard)
-    title = GraphQL::Batch.batch do
-      RecordLoader.for(Product).load(product.id).then(&:title)
-    end
-    assert_equal product.title, title
+def test_single_query
+  product = products(:snowboard)
+  title = GraphQL::Batch.batch do
+    RecordLoader.for(Product).load(product.id).then(&:title)
   end
+  assert_equal product.title, title
+end
 ```
 
 ## Development
diff --git a/graphql-batch.gemspec b/graphql-batch.gemspec
index a716bf6..f4bc6b6 100644
--- a/graphql-batch.gemspec
+++ b/graphql-batch.gemspec
@@ -1,7 +1,4 @@
-# coding: utf-8
-lib = File.expand_path('../lib', __FILE__)
-$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
-require 'graphql/batch/version'
+require_relative 'lib/graphql/batch/version'
 
 Gem::Specification.new do |spec|
   spec.name          = "graphql-batch"
@@ -20,7 +17,7 @@ Gem::Specification.new do |spec|
 
   spec.metadata['allowed_push_host'] = "https://rubygems.org"
 
-  spec.add_runtime_dependency "graphql", ">= 1.3", "< 2"
+  spec.add_runtime_dependency "graphql", ">= 1.10", "< 2"
   spec.add_runtime_dependency "promise.rb", "~> 0.7.2"
 
   spec.add_development_dependency "byebug" if RUBY_ENGINE == 'ruby'
diff --git a/lib/graphql/batch.rb b/lib/graphql/batch.rb
index dca20fe..0979cc1 100644
--- a/lib/graphql/batch.rb
+++ b/lib/graphql/batch.rb
@@ -16,29 +16,17 @@ def self.batch(executor_class: GraphQL::Batch::Executor)
     end
 
     def self.use(schema_defn, executor_class: GraphQL::Batch::Executor)
-      # Support 1.10+ which passes the class instead of the definition proxy
-      schema = schema_defn.is_a?(Class) ? schema_defn : schema_defn.target
-      current_gem_version = Gem::Version.new(GraphQL::VERSION)
-      if current_gem_version >= Gem::Version.new("1.6.0")
-        instrumentation = GraphQL::Batch::SetupMultiplex.new(schema, executor_class: executor_class)
-        schema_defn.instrument(:multiplex, instrumentation)
-        if schema.mutation
-          if current_gem_version >= Gem::Version.new('1.9.0.pre3') &&
-              (schema.mutation.is_a?(Class) || schema.mutation.metadata[:type_class])
-            require_relative "batch/mutation_field_extension"
-            schema.mutation.fields.each do |name, f|
-              field = f.respond_to?(:type_class) ? f.type_class : f.metadata[:type_class]
-              field.extension(GraphQL::Batch::MutationFieldExtension)
-            end
-          else
-            schema_defn.instrument(:field, instrumentation)
-          end
+      instrumentation = GraphQL::Batch::SetupMultiplex.new(schema_defn, executor_class: executor_class)
+      schema_defn.instrument(:multiplex, instrumentation)
+
+      if schema_defn.mutation
+        require_relative "batch/mutation_field_extension"
+
+        schema_defn.mutation.fields.each do |name, field|
+          field.extension(GraphQL::Batch::MutationFieldExtension)
         end
-      else
-        instrumentation = GraphQL::Batch::Setup.new(schema, executor_class: executor_class)
-        schema_defn.instrument(:query, instrumentation)
-        schema_defn.instrument(:field, instrumentation)
       end
+
       schema_defn.lazy_resolve(::Promise, :sync)
     end
   end
@@ -47,5 +35,4 @@ def self.use(schema_defn, executor_class: GraphQL::Batch::Executor)
 require_relative "batch/version"
 require_relative "batch/loader"
 require_relative "batch/executor"
-require_relative "batch/setup"
 require_relative "batch/setup_multiplex"
diff --git a/lib/graphql/batch/loader.rb b/lib/graphql/batch/loader.rb
index 0bc8ea2..646edf2 100644
--- a/lib/graphql/batch/loader.rb
+++ b/lib/graphql/batch/loader.rb
@@ -34,7 +34,7 @@ def current_executor
         unless executor
           raise GraphQL::Batch::NoExecutorError, 'Cannot create loader without'\
             ' an Executor. Wrap the call to `for` with `GraphQL::Batch.batch`'\
-            ' or use `GraphQL::Batch::Setup` as a query instrumenter if'\
+            ' or use `GraphQL::Batch::SetupMultiplex` as a query instrumenter if'\
             ' using with `graphql-ruby`'
         end
 
diff --git a/lib/graphql/batch/setup.rb b/lib/graphql/batch/setup.rb
deleted file mode 100644
index 3967586..0000000
--- a/lib/graphql/batch/setup.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-module GraphQL::Batch
-  class Setup
-    class << self
-      def start_batching(executor_class)
-        GraphQL::Batch::Executor.start_batch(executor_class)
-      end
-
-      def end_batching
-        GraphQL::Batch::Executor.end_batch
-      end
-
-      def instrument_field(schema, type, field)
-        return field unless type == schema.mutation
-        old_resolve_proc = field.resolve_proc
-        field.redefine do
-          resolve(->(obj, args, ctx) {
-            GraphQL::Batch::Executor.current.clear
-            begin
-              ::Promise.sync(old_resolve_proc.call(obj, args, ctx))
-            ensure
-              GraphQL::Batch::Executor.current.clear
-            end
-          })
-        end
-      end
-    end
-
-    def initialize(schema, executor_class:)
-      @schema = schema
-      @executor_class = executor_class
-    end
-
-    def before_query(query)
-      Setup.start_batching(@executor_class)
-    end
-
-    def after_query(query)
-      Setup.end_batching
-    end
-
-    def instrument(type, field)
-      Setup.instrument_field(@schema, type, field)
-    end
-  end
-end
diff --git a/lib/graphql/batch/setup_multiplex.rb b/lib/graphql/batch/setup_multiplex.rb
index 8ed05de..940d2a7 100644
--- a/lib/graphql/batch/setup_multiplex.rb
+++ b/lib/graphql/batch/setup_multiplex.rb
@@ -6,15 +6,11 @@ def initialize(schema, executor_class:)
     end
 
     def before_multiplex(multiplex)
-      Setup.start_batching(@executor_class)
+      GraphQL::Batch::Executor.start_batch(@executor_class)
     end
 
     def after_multiplex(multiplex)
-      Setup.end_batching
-    end
-
-    def instrument(type, field)
-      Setup.instrument_field(@schema, type, field)
+      GraphQL::Batch::Executor.end_batch
     end
   end
 end
diff --git a/test/support/schema.rb b/test/support/schema.rb
index a0501e9..3e4e537 100644
--- a/test/support/schema.rb
+++ b/test/support/schema.rb
@@ -157,41 +157,17 @@ def resolve
   end
 end
 
-if ENV["TESTING_LEGACY_DEFINITION_LAYER"] != "true"
-  class MutationType < GraphQL::Schema::Object
-    field :increment_counter, mutation: IncrementCounterMutation
-    field :counter_loader, mutation: CounterLoaderMutation
-    field :no_op, mutation: NoOpMutation
-  end
-else
-  MutationType = GraphQL::ObjectType.define do
-    name "Mutation"
-
-    field :incrementCounter, CounterType.to_non_null_type do
-      resolve ->(_, _, ctx) { ctx[:counter][0] += 1; CounterLoader.load(ctx[:counter]) }
-    end
-
-    field :counterLoader, !types.Int do
-      resolve ->(_, _, ctx) {
-        CounterLoader.load(ctx[:counter])
-      }
-    end
-
-    field :noOp, QueryType.to_non_null_type do
-      resolve ->(_, _, ctx) { Hash.new }
-    end
-  end
+class MutationType < GraphQL::Schema::Object
+  field :increment_counter, mutation: IncrementCounterMutation
+  field :counter_loader, mutation: CounterLoaderMutation
+  field :no_op, mutation: NoOpMutation
 end
 
 class Schema < GraphQL::Schema
   query QueryType
   mutation MutationType
 
-  if ENV["TESTING_LEGACY_DEFINITION_LAYER"] != "true"
-    use GraphQL::Execution::Interpreter
-    # This probably has no effect, but just to get the full test:
-    use GraphQL::Analysis::AST
-  end
-
+  use GraphQL::Execution::Interpreter
+  use GraphQL::Analysis::AST
   use GraphQL::Batch
 end