This gem works in conjuction with Jets to allow you to run a Rails application on AWS Lambda. Jets automatically adds this gem to a Rails application as part of Mega Mode Rails Support. Here's a Blog Post Tutorial that covers Mega Mode: Jets Mega Mode: Run Rails on AWS Lambda.
Mega Mode Video Tutorial:
This gem is not meant to be used standalone. You can enable it though by adding to your Rails Gemfile and setting the JETS_MEGA=1 env var.
For more information about Jets and Rails Support refer to: