clojurescript

A set of instructions for writing, editing, reviewing, or discussing ClojureScript code, which compiles to JavaScript and runs in browsers or other JavaScript runtimes.

In plain words
What is it for?
Use it for ClojureScript files and projects, including configurations for tools such as shadow-cljs or cljs.test.
Why use it?
It provides language-specific guidance for syntax, JavaScript interaction, compilation, errors, and project workflows.

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/brackendev/clojurescript-skills/clojurescript
Any agent
npx skills add brackendev/clojurescript-skills --skill clojurescript
Clone the repo
git clone --depth 1 https://github.com/brackendev/clojurescript-skills

Made for: Claude Code, Codex.

Per session 349 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,078 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 $0.00349 $0.05078
Opus 5 $0.00175 $0.02539
Sonnet 5 $0.00070 $0.01016
Haiku 4.5 $0.00035 $0.00508

Measured yesterday against content hash f238bf72710b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

clojurescript 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 yesterday.

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.

.apm/skills/clojurescript/SKILL.md · 425 lines

How it starts

The opening of the file, as written. The whole thing — 425 lines — stays where its author put it; the contents beside it link to each section on GitHub.

ClojureScript

Layered on top of the clojure skill, which defines host-neutral Clojure family guidance. This skill applies only to ClojureScript (.cljs files, .cljc files compiled to JS, ClojureScript deps.edn projects, shadow-cljs.edn, figwheel-main.edn). It overrides the baseline for JavaScript interop, externs inference, macro stage separation (:require-macros, :refer-macros, :include-macros), host-typed exception handling (catch :default, js/Error), JS-flavored numerics and truthiness, host-specific aliases (goog.object, goog.string, goog.dom), and the cljs.main project workflow.

JVM and ClojureDart deltas live in their own packages (clojure-jvm-skills, clojuredart-skills). Do not apply this skill's JS interop, externs, or catch :default rules to those dialects.

Key Rules

  1. Property access uses a leading hyphen. (.-prop obj) reads a property; (set! (.-prop obj) v) assigns it. (.method obj args) calls a method. The hyphen is what distinguishes property access from method invocation in ClojureScript.
  2. Globals live under the js/ namespace. js/document, js/window, js/Promise, js/Error. There is no other path to native globals.
  3. Catch with :default when you want to catch everything; otherwise name a JS type. ClojureScript supports (catch :default e ...). Prefer js/Error and its subclasses (js/TypeError, js/RangeError, js/SyntaxError) when the failure mode has a named JS type.
  4. Macros must be defined in .clj or .cljc files and required with :require-macros, :refer-macros, or :include-macros. Macros and functions run in different compilation stages. A macro and a function may share the same name.
  5. :import is only for Google Closure classes. (:import [goog Uri]) works; (:import [java.util Date]) does not exist on this host. Use (:require ...) and js/ for everything else.
  6. No gen-class, no refs, no agents, no STM. Atoms are the only built-in state primitive. Concurrency primitives that depend on multiple OS threads do not exist; JS has a single execution thread per realm.
  7. Numbers are JavaScript numbers. There is no Ratio, BigDecimal, or BigInt literal. (= 0.0 0) evaluates to true. Use js/BigInt directly when arbitrary-precision integers are required.
  8. Use ^boolean to avoid checked-if. It is the only type hint with runtime significance for code generation, and it suppresses the runtime check that copes with JavaScript's wider falsy set (0, "", NaN, null, undefined).
  9. Use ^js and ^js/Foo.Bar to drive externs inference for advanced compilation. Without hints on foreign JavaScript values, the Google Closure Compiler may rename property names and break interop at advanced optimization levels.
  10. Convert at the boundary, not at every use. Use js->clj and clj->js once at the interop boundary to translate between persistent collections and native JS objects, then operate on Clojure data inside the namespace.

Read the full file on GitHub · 425 lines

Files

What ships with it

2 files 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. yesterday First seen · 425 lines · 349 tokens per session scan A f238bf72710b

Subscribe to this mod's changes

clojurescript is a skill published in the GitHub repository brackendev/clojurescript-skills (1 stars, last pushed 1mo ago), licensed MIT. It adds 349 tokens to every session and 5,078 once invoked, about $0.0017 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 2026-08-31.

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