codable-patterns

Encode and decode Swift types using Codable (Encodable & Decodable) with JSONEncoder, JSONDecoder, and related APIs. Targets Swift 6.2 / iOS 26+.

When all stored properties are themselves Codable, the compiler synthesizes conformance automatically:

Prefer Decodable for read-only API responses and Encodable for write-only. Use Codable only when both directions are required.

Encode and decode Swift types to and from JSON, property lists, and other external representations using Codable, JSONEncoder, and JSONDecoder. Use when implementing API response parsing, custom CodingKeys for key remapping, custom init(from:) or encode(to:) for complex transformations, nested or flattened JSON structures, heterogeneous array decoding, date and data decoding strategies, lossy array wrappers, Codable integration with URLSession, SwiftData, or UserDefaults, or when configuring encoder/decoder output formatting and key strategies. Source: dpearson2699/swift-ios-skills.