You can build "easy" on top of "simple", but it's hard to do the reverse.
– @weavejester
Biff speeds up web development by providing as much functionality as possible out-of-the-box while making it easy to swap out, modify, or remove parts as your project grows. It's built with solo developers in mind and is quite opinionated in its approach to serving that use case.
The goal is to provide the benefits of a web framework without sacrificing the simplicity that makes Clojure great.
See also: Should you use Biff?
Biff is developed by myself, Jacob O'Bryant. I started it while I was a full-time entrepreneur, working on apps like Yakread and The Sample (each of which is built with Biff and has 10-15k lines of code). See r/Clojure for comments about Biff.
Biff is generously sponsored by JUXT and other individuals, and it has received multiple grants from Clojurists Together.