Hanami (formerly Lotus) is a newish Ruby framework for building web applications. Here's a few things I learned about it coming from Rails.
Leveraging RSpec metadata to control how specs are run with examples for altering database mode and toggling behavior based on spec directory
ActiveRecord will try hard to infer the inverse relation for your associations, but you may benefit from setting the inverse_of option wherever possible
Learn how to use RSpec metadata to add declarative ways to toggle features like Rails caching during test runs