Swift Code Composer
Swift Technical Interview Prep
I've created this knowledge base and resources to help iOS engineers prepare for a staff/principle level technical interviews.
Short multiple-choice checks per topic, or a mega quiz drawn from every topic that has questions in the bank.
Mega quiz — all topics
10 questions chosen at random from the combined pool across every topic.
Start mega quiz →By topic
- Topic quiz →Topic
Swift language features
Value vs reference, optionals, protocols, ARC, closures, errors, property wrappers, Sendable.
- Topic quiz →Topic
Architecture & design patterns
MVVM, coordinators, DI, clean architecture.
- Topic quiz →Topic
UIKit & SwiftUI internals
Lifecycle, responder chain, layout, collection view, SwiftUI state, interop.
- Topic quiz →Topic
Concurrency
async/await, actors, structured concurrency, tasks, cancellation, GCD migration.
- Topic quiz →Topic
Performance & optimization
Instruments, scrolling, memory, launch time, dispatch, images.
- Topic quiz →Topic
Networking & data
URLSession, Codable, offline-first, pagination.
- Topic quiz →Topic
Testing
XCTest, mocks, UI tests, async tests, snapshots, coverage.
- Topic quiz →Topic
Data persistence
Core Data, SwiftData, Keychain, files, SQLite, migrations.
- Topic quiz →Topic
System design & soft skills
Refactors, debt, reviews, onboarding, ambiguity, collaboration.