swiftui-performance

swiftui-performance is a skill for Claude Code from JordanCoin/ios-skills-collection. It costs 59 tokens per session (4,130 once invoked), scanned A, original, no licence file.

A guide to finding and fixing slow SwiftUI apps, Apple’s framework for building app screens. It covers slow rendering, uneven scrolling, unnecessary view updates, memory and CPU use, layout work, lazy loading, and profiling with Instruments.

In plain words
What is it for?
Use it to audit SwiftUI rendering, scrolling, view updates, memory usage, layout behavior, view identity, or body evaluation costs.
Why use it?
It helps identify why an interface is lagging or doing too much work instead of relying on guesswork.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the ios-skills plugin — 198 skills, 2 hooks shipped together

Good fit Use it to audit SwiftUI rendering, scrolling, view updates, memory usage, layout behavior, view identity, or body evaluation costs.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jordancoin/ios-skills-collection/dpearson2699-swiftui-performance
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.

Any agent
npx skills add JordanCoin/ios-skills-collection --skill dpearson2699-swiftui-performance
Clone the repo
git clone --depth 1 https://github.com/JordanCoin/ios-skills-collection

Made for: Claude Code.

Or install ios-skills, the plugin that ships this one along with the rest of its 198 skills, 2 hooks.

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 swiftui-performance

README.md
[![agentmods](https://agentmods.dev/badge/skills/jordancoin/ios-skills-collection/dpearson2699-swiftui-performance/github.svg)](https://agentmods.dev/skills/jordancoin/ios-skills-collection/dpearson2699-swiftui-performance)
Your own site
<a href="https://agentmods.dev/skills/jordancoin/ios-skills-collection/dpearson2699-swiftui-performance"><img src="https://agentmods.dev/badge/skills/jordancoin/ios-skills-collection/dpearson2699-swiftui-performance/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for swiftui-performance

Your own site · 80×15
<a href="https://agentmods.dev/skills/jordancoin/ios-skills-collection/dpearson2699-swiftui-performance"><img src="https://agentmods.dev/badge/skills/jordancoin/ios-skills-collection/dpearson2699-swiftui-performance.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 59 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,130 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. 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 $0.00059 $0.04130
Opus 5 $0.00030 $0.02065
Sonnet 5 $0.00012 $0.00826
Haiku 4.5 $0.00006 $0.00413

Measured 9d ago against content hash bc5a32918ca6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

swiftui-performance 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 9d 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.

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.

skills/dpearson2699--swiftui-performance/SKILL.md · 486 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Files

What ships with it

5 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. 9d ago First seen · 486 lines · 59 tokens per session scan A bc5a32918ca6

Subscribe to this mod's changes

swiftui-performance is a skill published in the GitHub repository JordanCoin/ios-skills-collection (5 stars, last pushed 2d ago), with no licence file. It adds 59 tokens to every session and 4,130 once invoked, about $0.0003 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 2026-09-03.

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