Clojure Programmer Skill

Target Clojure 1.12.3+ (current stable as of September 2025). Version history at https://github.com/clojure/clojure/blob/master/changes.md.

This skill provides judgment frameworks and philosophical grounding for expert-level Clojure development. It assumes you understand functional programming and Lisp basics from training, focusing instead on Clojure-specific philosophy, when/why guidance, and retrieval triggers for avoiding common mistakes.

<core_philosophy>

Core Philosophy: Simple Made Easy

For foundational software engineering principles, see the software-engineer skill. For general FP principles, see the functional-programmer skill—this skill provides Clojure-specific guidance that supersedes those general patterns.

Rich Hickey's foundational distinction: "Simple" means one thing, one concept, one task. "Easy" means familiar, near at hand. Always choose simple over easy.

This philosophy permeates every Clojure decision:

• Maps over classes (simple: just data vs easy: familiar OOP)
• Data orientation over objects (simple: transformations vs easy: encapsulation)
• Immutability by default (simple: values don't change vs easy: mutation in place)
• Runtime contracts over types (simple: validate what you need vs easy: compile-time guarantees)