I've played around with it and Hanami seems to be targeting the larger complex apps that eventually become become painful with Rails due to fat models / control

I've played around with it and Hanami seems to be targeting the larger complex apps that eventually become become painful with Rails due to fat models / controllers among other things. Hanami seems to be inspired by Uncle Bob's Clean Architecture. IMO it's pretty nicely done and a good example of how Clean Arch can be implemented. Worth playing with if only to get a feel for it's structure and potentially influence your Rails apps.