claude: Skill for Claude Code

.claude/skills/go-concurrency/SKILL.md

go-concurrency is a skill for Claude Code from zarldev/claude. It costs 40 tokens per session (2,312 once invoked), scanned A, original, no licence file.

A collection of Go patterns for concurrent programs, where multiple tasks run at the same time. It covers goroutines, channels, synchronisation tools, worker pools, and errgroup.

In plain words
What is it for?
Writing concurrent Go code, managing goroutine lifecycles, coordinating workers, and debugging race conditions.
Why use it?
It helps structure concurrent work and investigate problems such as goroutines that do not stop or race conditions.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is zarldev/claude's own configuration. It tells Claude Code how to work on claude itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything claude configures →

Reuse

Borrowing it

Nothing to install: this file belongs to zarldev/claude. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/zarldev/claude/main/.claude/skills/go-concurrency/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/zarldev/claude

Made for: Claude Code.

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 go-concurrency

README.md
[![agentmods](https://agentmods.dev/badge/skills/zarldev/claude/go-concurrency.svg)](https://agentmods.dev/skills/zarldev/claude/go-concurrency)
Your own site
<a href="https://agentmods.dev/skills/zarldev/claude/go-concurrency"><img src="https://agentmods.dev/badge/skills/zarldev/claude/go-concurrency.svg" alt="Measured on agentmods" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,312 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 5.1 $0.00040 $0.02312
Opus 5 $0.00020 $0.01156
Sonnet 5 $0.00008 $0.00462
Haiku 4.5 $0.00004 $0.00231

Measured 6d ago against content hash 016703446d48, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

go-concurrency scanned grade A with 1 finding 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 6d ago.

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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

result, err := fetch(ctx, url)
.claude/skills/go-concurrency/SKILL.md · 461 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 6d ago First seen · 461 lines · 40 tokens per session scan A 016703446d48

Subscribe to this mod's changes

go-concurrency is a skill published in the GitHub repository zarldev/claude (2 stars, last pushed 6mo ago), with no licence file. It adds 40 tokens to every session and 2,312 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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