Bottom Up vs Top Down Design in Clojure - Mark Bastian

What this video covers

Mark Bastian contrasts top-down object-oriented design with bottom-up, data-oriented design in Clojure. He models a board game as plain data plus small composable functions and compares it with a roughly 22-class OOP version.

Why it surfaced in Hacker News

HN repeatedly recommends it as the talk that made data-oriented, REPL-driven bottom-up design click.

Recommendation context

Short excerpts from positive mentions. Open the source to read the full Hacker News discussion.

“One of my favorite videos from Clojure Conj last year”

“I highly recommend this talk from Mark Bastian in Clojure/conj 2015”

“Here's a good video highlighting the difference of approach. Well worth watching.”