module ActiveModelSerializers::KeyTransform

def dash(value)

Other tags:
    See: {https://github.com/rails/rails/blob/master/activesupport/lib/active_support/inflector/methods.rb#L185-L187 - ActiveSupport::Inflector.dasherize} 
def dash(value)
  case value
  when Hash then value.deep_transform_keys! { |key| dash(key) }
  when Symbol then dash(value.to_s).to_sym
  when String then value.underscore.dasherize
  else value
  end
end