```ruby
if RUBY_ENGINE == "rbx"
  require "codeclimate-test-reporter"
  CodeClimate::TestReporter.start
end

$LOAD_PATH.unshift File.expand_path('../../lib', __FILE__)

require 'dry-types'

begin
  require 'byebug'
  require 'mutant'

  module Mutant
    class Selector
      class Expression < self
        def call(_subject)
          integration.all_tests
        end
      end # Expression
    end # Selector
  end # Mutant
rescue LoadError; end

Dir[Pathname(__dir__).join('shared/*.rb')].each(&method(:require))

RSpec.configure do |config|
  config.before do
    @types = Dry::Types.container._container.keys

    module Test
      def self.remove_constants
        constants.each { |const| remove_const(const) }
        self
      end
    end
  end

  config.after do
    container = Dry::Types.container._container
    (container.keys - @types).each { |key| container.delete(key) }
    Dry::Types.instance_variable_set('@type_map', ThreadSafe::Cache.new)

    Object.send(:remove_const, Test.remove_constants.name)
  end
end
```

Use concurrent in spec after hook
user
```ruby
if RUBY_ENGINE == "rbx"
  require "codeclimate-test-reporter"
  CodeClimate::TestReporter.start
end

$LOAD_PATH.unshift File.expand_path('../../lib', __FILE__)

require 'dry-types'

begin
  require 'byebug'
  require 'mutant'

  module Mutant
    class Selector
      class Expression < self
        def call(_subject)
          integration.all_tests
        end
      end # Expression
    end # Selector
  end # Mutant
rescue LoadError; end

Dir[Pathname(__dir__).join('shared/*.rb')].each(&method(:require))

RSpec.configure do |config|
  config.before do
    @types = Dry::Types.container._container.keys

    module Test
      def self.remove_constants
        constants.each { |const| remove_const(const) }
        self
      end
    end
  end

  config.after do
    container = Dry::Types.container._container
    (container.keys - @types).each { |key| container.delete(key) }
    Dry::Types.instance_variable_set('@type_map', Concurrent::Map.new)

    Object.send(:remove_const, Test.remove_constants.name)
  end
end
```
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