How do I install the Solid Swift skill?

Run npx skillmds@latest add fusengine/solid-swift-3 in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

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Which AI agents work with Solid Swift?

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Is Solid Swift free to use?

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Who published Solid Swift?

fusengine (@fusengine) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Solid Swift by fusengine — Agent Skill

Name: Solid Swift
Rating: 4.5 (4 reviews)
Author: fusengine

File contents

SOLID Swift - Apple Best Practices 2026

Agent Workflow (MANDATORY)

Before ANY implementation, use TeamCreate to spawn 3 agents:

fuse-ai-pilot:explore-codebase - Analyze existing architecture
fuse-ai-pilot:research-expert - Verify Swift/Apple docs via Apple Docs MCP + Context7
XcodeBuildMCP - Build validation after code changes. Then run fuse-ai-pilot:sniper.

DRY - Reuse Before Creating (MANDATORY)

Before writing ANY new code:

Grep the codebase for similar protocols, services, or logic
Check shared locations: Core/Extensions/, Core/Utilities/, Core/Protocols/
If similar code exists -> extend/reuse instead of duplicate
If code will be used by 2+ features -> create it in Core/ directly

Architecture (Features Modular MANDATORY)

Layer	Location	Max Lines
Views	`Features/[Feature]/Views/`	80
ViewModels	`Features/[Feature]/ViewModels/`	100
Services	`Features/[Feature]/Services/`	100
Protocols	`Features/[Feature]/Protocols/`	30
Shared	`Core/{Models,Protocols,Services,Extensions,Utilities}/`	-

NEVER use flat Sources/ structure - always Features/[Feature]/

Critical Rules (MANDATORY)

Rule	Value
File limit	100 lines (split at 90)
ViewModels	`@MainActor @Observable`
Protocols	`Features/[Feature]/Protocols/` or `Core/Protocols/` ONLY
Models	`Sendable` structs
Documentation	`///` on all public APIs
Previews	Every View MUST have `#Preview`

Reference Guide

Concepts

Topic	Reference	When to consult
SOLID Overview	solid-principles.md	Quick reference all principles
SRP	single-responsibility.md	Fat views/VMs, splitting files
OCP	open-closed.md	Adding providers, extensibility
LSP	liskov-substitution.md	Protocol contracts, testing
ISP	interface-segregation.md	Fat protocols, splitting
DIP	dependency-inversion.md	Injection, testing, mocking
Concurrency	concurrency-patterns.md	Actors, @MainActor, Sendable
Anti-Patterns	anti-patterns.md	Code smells detection

Templates

Template	When to use
view.md	SwiftUI View with subviews and #Preview
viewmodel.md	@Observable ViewModel with @MainActor
service.md	API Service, Mock, Cache actor
protocol.md	Service protocol, CQRS, Auth
model.md	Model, DTO, Error, Enum

Forbidden

Anti-Pattern	Fix
Files > 100 lines	Split at 90
Protocols in impl files	Move to `Protocols/` directory
`ObservableObject`	Use `@Observable`
Completion handlers	Use `async/await`
Missing `#Preview`	Add preview for every View
Non-Sendable in async	Use `struct` with `let`
Flat `Sources/` structure	Use `Features/[Feature]/`

---name: solid-swift-3description: SOLID principles for Swift 6 and SwiftUI (iOS 26+). Files < 100 lines, protocols separated, @Observable, actors, Preview-driven development. Features Modular MANDATORY.---# SOLID Swift - Apple Best Practices 2026## Agent Workflow (MANDATORY)Before ANY implementation, use `TeamCreate` to spawn 3 agents:1. **fuse-ai-pilot:explore-codebase** - Analyze existing architecture2. **fuse-ai-pilot:research-expert** - Verify Swift/Apple docs via Apple Docs MCP + Context73. **XcodeBuildMCP** - Build validation after code changes. Then run **fuse-ai-pilot:sniper**.---## DRY - Reuse Before Creating (MANDATORY)**Before writing ANY new code:**1. **Grep the codebase** for similar protocols, services, or logic2. Check shared locations: `Core/Extensions/`, `Core/Utilities/`, `Core/Protocols/`3. If similar code exists -> extend/reuse instead of duplicate4. If code will be used by 2+ features -> create it in `Core/` directly---## Architecture (Features Modular MANDATORY)| Layer | Location | Max Lines ||-------|----------|-----------|| Views | `Features/[Feature]/Views/` | 80 || ViewModels | `Features/[Feature]/ViewModels/` | 100 || Services | `Features/[Feature]/Services/` | 100 || Protocols | `Features/[Feature]/Protocols/` | 30 || Shared | `Core/{Models,Protocols,Services,Extensions,Utilities}/` | - |**NEVER use flat `Sources/` structure - always `Features/[Feature]/`**---## Critical Rules (MANDATORY)| Rule | Value ||------|-------|| File limit | 100 lines (split at 90) || ViewModels | `@MainActor @Observable` || Protocols | `Features/[Feature]/Protocols/` or `Core/Protocols/` ONLY || Models | `Sendable` structs || Documentation | `///` on all public APIs || Previews | Every View MUST have `#Preview` |---## Reference Guide### Concepts| Topic | Reference | When to consult ||-------|-----------|-----------------|| **SOLID Overview** | [solid-principles.md](references/solid-principles.md) | Quick reference all principles || **SRP** | [single-responsibility.md](references/single-responsibility.md) | Fat views/VMs, splitting files || **OCP** | [open-closed.md](references/open-closed.md) | Adding providers, extensibility || **LSP** | [liskov-substitution.md](references/liskov-substitution.md) | Protocol contracts, testing || **ISP** | [interface-segregation.md](references/interface-segregation.md) | Fat protocols, splitting || **DIP** | [dependency-inversion.md](references/dependency-inversion.md) | Injection, testing, mocking || **Concurrency** | [concurrency-patterns.md](references/concurrency-patterns.md) | Actors, @MainActor, Sendable || **Anti-Patterns** | [anti-patterns.md](references/anti-patterns.md) | Code smells detection |### Templates| Template | When to use ||----------|-------------|| [view.md](references/templates/view.md) | SwiftUI View with subviews and #Preview || [viewmodel.md](references/templates/viewmodel.md) | @Observable ViewModel with @MainActor || [service.md](references/templates/service.md) | API Service, Mock, Cache actor || [protocol.md](references/templates/protocol.md) | Service protocol, CQRS, Auth || [model.md](references/templates/model.md) | Model, DTO, Error, Enum |---## Forbidden| Anti-Pattern | Fix ||--------------|-----|| Files > 100 lines | Split at 90 || Protocols in impl files | Move to `Protocols/` directory || `ObservableObject` | Use `@Observable` || Completion handlers | Use `async/await` || Missing `#Preview` | Add preview for every View || Non-Sendable in async | Use `struct` with `let` || Flat `Sources/` structure | Use `Features/[Feature]/` |

Frequently asked questions

Solid Swift