swift-coding-standards

name	swift-coding-standards
description	Enforces AppVerk Swift coding standards across all code.
activation	Load when writing or reviewing Swift code

Skill: swift-coding-standards

Overview

Enforces AppVerk Swift coding standards across all code.

Naming

• lowerCamelCase for variables, functions, and enum cases.
• UpperCamelCase for types, protocols, and structs.
• UPPER_SNAKE_CASE for global constants.
• Acronyms and initialisms are treated as regular words: userId, urlString.

Optionals

• Never force-unwrap (!). Always use guard let or if let.
• Use ?? for defaults: let name = optionalName ?? "Unknown".
• Prefer optional chaining (optional?.property) over manual unwrapping when just reading.
• Use guard let at the top of functions for early exit on missing required values.

Access Control

• Default to private or internal.
• Use public only for library API surfaces.
• Mark classes as final when inheritance is not intended.

Value vs Reference Types

• Default to struct for data models and configuration.
• Use class only when identity matters or shared mutable state is required.
• Use actor for thread-safe mutable state (see swift-concurrency-patterns).

Protocol-Oriented Programming

• Prefer protocols + extensions over deep class hierarchies.
• Use protocol composition (some ProtocolA & ProtocolB) for constraints.

Generics

• Prefer some Collection for parameters.
• Use any Collection for stored properties and return types where erasure is needed.

Comments and Style

• Use // MARK: for section headers in large files.
• Use /// doc comments for public APIs.
• No commented-out code in committed files.
• Omit self. when implicit.
• Prefer isEmpty over count == 0.
• Prefer first / last over manual indexing.