Hanami core team-member here :)

We re-did our homepage recently, and we should make these things clearer. They're legitimate concerns and questions. We agree you don't have to write bad code in Rails, and we don't pretend that we can prevent bad code in Hanami. Instead we give application builders the tools to architect their applications in the way they desire. Really what we're doing is building an *option* for building Ruby apps that may speak better to some people. If you're completely happy with Rails then there's no reason to change. Still, you may learn something that'll help you build Rails apps by seeing how we do things. Additionally, it's completely modular: you can pull parts of Hanami into a Rails app. The most popular one people pull into Rails apps is dry-validation [1]

Some concrete differences:

- We have small, simple API's. Rails core classes have hundreds of methods for convenience, not to mention dozens of core extensions (a.k.a. monkey patches) to base Ruby classes. We prefer small, narrowly focused classes over large ones with many responsibilities.

- We have a dependency injection framework dry-system [2] included by default. This lets you write `include Deps["repos.article_repo"] to get an automatically instantiated (and now memoized!) `Repos::ArticleRepo.new` within your class. This makes dependencies trivial to stub out, and it also declares your dependencies in a single place, instead of littering constants throughout your code.

- We have sub-applications called Slices. Similar to Rails Engines but well... good, since they're a first-class concept that we encourage. Importantly, they're independently deployable. You can export and import components across slices, too. We can't tell you how to slice up your application, but we give you the tools to decide for yourself.

[1]: https://hanakai.org/learn/dry/dry-validation

[2]: https://hanakai.org/learn/dry/dry-system

user:	cllns_ruby
created:	July 1, 2026
karma:	18
about:	Hanakai core team member: Hanami, Dry, Rom https://hanakai.org/