module ActiveModelSerializers::KeyTransform

def camel(value)

Other tags:
    See: {https://github.com/rails/rails/blob/master/activesupport/lib/active_support/inflector/methods.rb#L66-L76 - ActiveSupport::Inflector.camelize} 
def camel(value)
  case value
  when Hash then value.deep_transform_keys! { |key| camel(key) }
  when Symbol then camel(value.to_s).to_sym
  when String then value.underscore.camelize
  else value
  end
end