```ruby
# frozen_string_literal: true
require 'bundler_diffgems/cli'
require 'bundler_diffgems/formatter/default'
require 'bundler_diffgems/formatter/md_table'
require 'bundler_diffgems/version'

module BundlerDiffgems
  def self.formatters
    @formatters ||= {
      default: Formatter::Default,
      md_table: Formatter::MdTable
    }
  end
end
```

Fix a bug that does not parallelize
user
```ruby
# frozen_string_literal: true
require 'parallel'
require 'bundler_diffgems/cli'
require 'bundler_diffgems/formatter/default'
require 'bundler_diffgems/formatter/md_table'
require 'bundler_diffgems/version'

module BundlerDiffgems
  def self.formatters
    @formatters ||= {
      default: Formatter::Default,
      md_table: Formatter::MdTable
    }
  end
end
```
assistant