write-swift SKILL.md skillA
write-swift from emilkowalski/skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add emilkowalski/skills/write-swift@git:20260915.85e8e23Pins git:20260915.85e8e23 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- emilkowalski/skills
- Path
skills/write-swift/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260915.85e8e23, committed Sep 15, 2026
- First version recorded
- Aug 21, 2026
- Size
- 42,445 bytes
- Repository stars
- 47,883
- License
- MIT
How to write modern Swift well — modeling with value types, Swift 6 data-race safety and approachable concurrency (@concurrent, main-actor-by-default, actors, task groups), protocols and generics (some vs any), API design, performance and ARC, Swift Testing, macros, and the modern language features agents don't know about yet. Use when writing, reviewing, or migrating Swift, or when a concurrency error, a hang, a data race, a retain cycle, or a performance problem needs fixing.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Write Swift ## Initial Response When this skill is first invoked without a specific question, respond only with: > I'm ready to help you write modern Swift, the way the language wants to be written. Do not provide any other information until the user asks a question. How to write Swift the way the language wants to be written, current through Swift 6.4. **Toolchain baseline: Swift 6.3** (current release as of August 2026). Everything here compiles on 6.3 unless marked ⚠, which flags unreleased Swift 6.4 features. Concurrency guidance assumes the Swift 6.2 model — if the project is on 6.1 or earlier, §3's rules about `async` and `@concurrent` do not apply. The through-line: **Swift is a progressive-disclosure language. Start with the simplest, most static, most single-threaded thing that works, and buy dynamism — concurrency, reference semantics, existentials, unsafe pointers — only where you can point at the reason.** Every rule below is an application of that. Model this hierarchy of defaults. Move down a level only with a reason you can state: | Need | Reach for | Move down only when | …
Read the whole file at its exact version.
How to install
mdr add emilkowalski/skills/write-swift@sha256:16a4b6adb74e338eThe line at the top of this page pins the label git:20260915.85e8e23, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_g36cc5y6htbk57fd)
5 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Aug 21, 2026 and Sep 15, 2026, about one every 13 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260915.85e8e23 latest | 2026-09-15 | 85e8e23 | 42,445 B | A | view · diff |
| git:20260915.0b85d4b | 2026-09-15 | 0b85d4b | 42,548 B | A | view · diff |
| git:20260821.8e1ec02 | 2026-08-21 | 8e1ec02 | 42,185 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (42445 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
emilkowalski/skills · 47,883 stars · license MIT · pushed 2026-10-11 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_g36cc5y6htbk57fd GET https://markdownregistry.com/api/v1/resolve?ref=emilkowalski/skills/write-swift GET https://markdownregistry.com/api/v1/blob/16a4b6adb74e338e55e704ce5753ad54d825438b8a63930eeaede9f3c04c9447
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
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