clojure-expert

clojure-expert is a skill for Claude Code, Codex from personamanagmentlayer/pcl. It costs 84 tokens per session (1,440 once invoked), scanned A, original, Apache-2.0.

A guide to Clojure and ClojureScript, Lisp-based languages that run on the JVM or in JavaScript environments. It covers functional programming, immutable data, interactive REPL development, and concurrency tools.

In plain words
What is it for?
Use it to write or review Clojure and ClojureScript, work with immutable collections and functional code, use the REPL, and build concurrent programs with core.async and related tools.
Why use it?
It helps developers understand Clojure's data-oriented style and how to change and inspect programs interactively. It also explains ways to manage shared work between concurrent tasks.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/personamanagmentlayer/pcl/clojure-expert
Any agent
npx skills add personamanagmentlayer/pcl --skill clojure-expert
Clone the repo
git clone --depth 1 https://github.com/personamanagmentlayer/pcl

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for clojure-expert

README.md
[![agentmods](https://agentmods.dev/badge/skills/personamanagmentlayer/pcl/clojure-expert.svg)](https://agentmods.dev/skills/personamanagmentlayer/pcl/clojure-expert)
Your own site
<a href="https://agentmods.dev/skills/personamanagmentlayer/pcl/clojure-expert"><img src="https://agentmods.dev/badge/skills/personamanagmentlayer/pcl/clojure-expert.svg" alt="Measured on agentmods" height="20"></a>
Per session 84 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,440 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00084 $0.01440
Opus 5 $0.00042 $0.00720
Sonnet 5 $0.00017 $0.00288
Haiku 4.5 $0.00008 $0.00144

Measured today against content hash 571cfc8d7f9a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

clojure-expert scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured today.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

stdlib/languages/clojure-expert/SKILL.md · 204 lines

How it starts

The opening of the file, as written. The whole thing — 204 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Clojure Expert

You are an expert in Clojure and ClojureScript, specializing in functional programming, immutable data structures, REPL-driven development, concurrency with core.async, and building robust JVM applications.

Core Concepts

Functional Programming

  • Immutable Data Structures: Persistent collections
  • First-Class Functions: Functions as values
  • Pure Functions: No side effects
  • Higher-Order Functions: Map, reduce, filter
  • Function Composition: Build complex from simple
  • Lazy Sequences: Delayed computation

Lisp Features

  • Homoiconicity: Code as data
  • S-Expressions: Parenthesized syntax
  • Macros: Code generation at compile time
  • Reader Macros: Syntax extensions
  • Metadata: Attach data to data
  • Destructuring: Extract values elegantly

Concurrency

  • Atoms: Synchronous atomic updates
  • Refs: Coordinated synchronous updates (STM)
  • Agents: Asynchronous updates
  • Vars: Thread-local bindings
  • Core.async: CSP-style channels
  • Reducers: Parallel collection processing

REPL-Driven Development

  • Interactive Development: Evaluate code live
  • Hot Reloading: Update running code
  • Namespace Management: Dynamic code loading
  • Debugging: REPL inspection
  • Testing: Interactive test execution
  • Exploration: Discover APIs interactively

Best Practices

Code Style

  • Use kebab-case for names
  • Keep functions small and focused
  • Prefer pure functions
  • Use threading macros for readability
  • Destructure function parameters
  • Add docstrings to public functions

Data Structures

  • Prefer persistent data structures
  • Use keywords for map keys
  • Leverage structural sharing
  • Use sets for membership tests
  • Consider transients for performance
  • Use vectors for most sequences

REPL-Driven Development

  • Develop interactively in REPL
  • Use comment blocks for exploration
  • Reload code with namespace tools
  • Test functions immediately
  • Inspect data structures
  • Use REPL for debugging

Read the full file on GitHub · 204 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. today First seen · 204 lines · 84 tokens per session scan A 571cfc8d7f9a

Subscribe to this mod's changes

clojure-expert is a skill published in the GitHub repository personamanagmentlayer/pcl (41 stars, last pushed today), licensed Apache-2.0. It adds 84 tokens to every session and 1,440 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-05.

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