Rails vs. Spring vs. Yesod

Rails is a web-application framework that includes everything needed to create database-backed web applications according to the Model-View-Controller (MVC) pattern.

A key element of Spring is infrastructural support at the application level: Spring focuses on the "plumbing" of enterprise applications so that teams can focus on application-level business logic, without unnecessary ties to specific deployment environments.

Yesod believes in the philosophy of making the compiler your ally, not your enemy. We use the type system to enforce as much as possible, from generating proper links, to avoiding XSS attacks, to dealing with character encoding issues. In general, if your code compiles, it works. And instead of declaring types everywhere you let the compiler figure them out for you with type inference.