Twenty-four weeks of production-grade Apple-platform engineering. From Swift 6 under strict concurrency on a Linux laptop to a multi-platform SwiftUI + SwiftData app that syncs over CloudKit, monetises with StoreKit 2, drives Live Activities from a Vapor backend, and clears App Review on the first attempt. Open-source-first. Free, forever.
§ I · The Program
Crunch Swift is the iOS and Apple-platform engineering specialization of the Code Crunch academy — a 24-week track authored for the Crunch Labs tier. It is built for engineers who want to take Apple-platform development seriously: not "build a to-do app in an afternoon", but Swift 6 under strict concurrency, SwiftUI rendered from layout internals, SwiftData synced to CloudKit, StoreKit 2 receipts verified server-side, and App Review cleared on the first submission.
You start on Linux. The first six weeks teach Swift the language and server-side Swift with Vapor — no Mac required, no Apple ID required, just the open-source toolchain from swift.org. From Week 7 you adopt Xcode, SwiftUI, and the simulator. From Week 15 the Apple Developer Program turns on for device deployment, push, and TestFlight. By Week 24 you have shipped a multi-platform app to TestFlight in five regions, survived a chaos drill, and written the runbook a future maintainer can read at three in the morning.
"This is not a 'build a to-do app in an afternoon' course. It is the curriculum we wish existed for engineers who want to take Apple-platform development seriously."— Crunch Swift, course README
§ II · Who It's For
Swift is opinionated about its audience. C1 (Code Crunch Convos) is the floor — you should be able to ship one non-trivial product in a typed OOP language before you arrive.
Ships Django, FastAPI, Rails, or Node every day. Wants to move into native iOS without losing the engineering discipline. Starts on Swift on Linux, then adopts the Mac.
Finished C8 (Web Dev) and loves designing interfaces. Wants a typed, declarative UI system with first-class animation, gesture, and accessibility primitives. SwiftUI, taught layout-system up.
Ships Flutter, React Native, or Kotlin Multiplatform today. Cannot yet hold their own in a senior iOS interview about navigation state, structured concurrency, or the SwiftUI diff algorithm. This track fixes that.
Runs the API. Wants the iOS client engineered with the same rigour as the server. Gets Vapor for the server-side Swift bridge, shared codable types, and a SwiftUI client with offline-first sync and conflict resolution.
§ III · Four Phases
The arc of the program is composed in four phases — six weeks each — each building on the last. Weeks 1–6 run on any laptop; Weeks 7+ require a Mac.
Swift the language, protocols and generics, structured concurrency, actors and Sendable, Vapor 4 server-side, shared SwiftPM packages. Runs on Linux, macOS, or WSL2 — no Apple ID needed.
Xcode, the SwiftUI mental model, the Layout protocol, state ownership (@State, @Observable, @Environment, @Bindable), navigation, SwiftData, MVVM and TCA, Combine vs AsyncSequence. Mac + simulator required.
URLSession with retries and offline-replay, Keychain and CloudKit sync with conflict resolution, Instruments-driven performance, accessibility, CryptoKit and the Secure Enclave, APNs and StoreKit 2 with server-side receipt validation. Apple Developer membership required from Week 15.
Multi-platform (iOS, iPadOS, macOS, watchOS, visionOS), WidgetKit, App Intents, Live Activities and ActivityKit, Swift Testing on GitHub Actions, fastlane to TestFlight, App Review, chaos drill, demo day.
§ IV · The Curriculum
Each entry corresponds to a folder in the GitHub repository with lecture notes, exercises, challenges, a quiz, homework, and a mini-project. Weeks 1–6 are Linux-runnable; Week 7 onward requires a Mac with Xcode 16+. Detailed acceptance criteria live in the syllabus.
Toolchain install (Linux + Mac) · SwiftPM · the REPL · value vs reference types · optionals · if let / guard let · collections · the parts that map cleanly from Java/Kotlin/TS, and the parts that do not.
swift run wordfreq CLI with Swift Testing
Protocol-oriented programming · associatedtype · some (opaque) vs any (existential) · type erasure · Result · throws/try · custom error enums.
Generic Cache<Key, Value> with TTL eviction
async functions · Task · TaskGroup · async let · cancellation · priority · @TaskLocal · structured vs unstructured tasks · why DispatchQueue is the past.
Parallel link-checker CLI with TaskGroup
Sendable, Strict ConcurrencyActors · @MainActor · nonisolated · Sendable and @Sendable closures · reentrancy · Swift 6 strict-concurrency mode · removing data races the compiler now catches.
Migrate a callback KV-store to an actor under strict concurrency
Vapor 4 project layout · routing · middleware · Content protocol · Fluent ORM (Postgres) · migrations · structured logging with swift-log · Dockerized test runs.
notes-api Vapor service with Postgres and bearer auth
Shared Models SwiftPM package · swift-nio event loops · Hummingbird alternative · OpenTelemetry-Swift basics · swift-collections · the codable bridge that pays for the rest of the track.
notes-cli + extracted NotesCore shared package
Xcode tour · schemes · asset catalogs · App and Scene · the View protocol · body as a function of state · the Layout protocol · modifier order. Mac + Xcode 16+ from this week onward.
"Hello, Notes" on iPhone SE and iPad Pro 13"
@State, @Observable, @Environment, @BindableProperty wrappers · the Observation framework · state ownership rules · view identity · the id() modifier · onChange(of:) · the SwiftUI re-render storm walkthrough.
Full CRUD via @Observable NotesStore
NavigationStack · NavigationSplitView · value-typed navigation · navigationDestination · deep links · universal links · state restoration · SceneStorage · AppStorage.
Sidebar-detail on iPad/Mac, stack on iPhone, notes://open/:id
SwiftData macros (@Model, @Attribute, @Relationship) · ModelContainer · @Query · #Predicate · lightweight migrations · performance footguns · Core Data interop.
Migrate Notes to SwiftData with many-to-many Tag
Plain SwiftUI + @Observable · MVVM as a discipline · The Composable Architecture (TCA) · unidirectional data flow · reducers, effects, dependencies · when "no architecture" is correct.
Search-and-filter feature in MVVM and TCA, with ADR
Combine fundamentals · operators · Combine in SwiftUI (onReceive) · AsyncSequence and AsyncStream · bridging Combine to async/await · back-pressure comparison · debounced search.
"Notes v1" — iPhone + iPad + Mac with SwiftData, deep links, XCUITest
URLSession configuration · async URLSession APIs · typed errors · Codable decoding strategies · retries with exponential backoff and jitter · request signing · request/response logging middleware.
NotesClient actor with offline-first write-replay against Vapor
FileManager · sandbox · App Group containers · Keychain (kSecClass, access groups) · atomic writes · SwiftData + CloudKit sync · conflict resolution policy · schema-versioned migrations.
CloudKit sync + deliberate two-device edit conflict
Code signing · provisioning profiles · device deployment · Instruments (Time Profiler, Hangs, Hitches, Allocations, Memory Graph) · the 16.67 ms budget · os_signpost · MetricKit. Apple Developer membership required from this week.
Profile Notes v1 on device, fix a real hang and a real hitch
VoiceOver · the accessibility tree · accessibilityLabel/Value/Hint · Dynamic Type · @ScaledMetric · color contrast · reduce motion · haptics (UIImpactFeedbackGenerator, CHHapticEngine) · the Accessibility Inspector.
Clear every Accessibility Inspector failure on Notes v1
ATS configuration · certificate pinning · Keychain access control · LocalAuthentication · CryptoKit (AES.GCM, Curve25519, SHA256) · the Secure Enclave (SecureEnclave.P256) · sensitive log scrubbing.
Pin a cert, sign each request with a Secure-Enclave key
APNs auth keys · device tokens · Notification Service Extensions · communication notifications · StoreKit 2 (Product, Transaction) · auto-renewing subscriptions · server-side receipt validation · Family Sharing · refunds.
"Notes Pro v1" — APNs + NSE + StoreKit 2 paywall, server-verified
SwiftUI multi-platform targets · #if os(...) discipline · Mac Catalyst vs SwiftUI-on-macOS-native · watchOS (WKApplication, complications) · visionOS basics (RealityKit, ImmersiveSpace, volumetric windows).
Notes Pro v1 running on four Apple platforms, side by side
WidgetKit · TimelineProvider · supported families · Lock Screen widgets · App Intents (the new contract) · Siri suggestions · Shortcuts gallery · Spotlight indexing with CSSearchableIndex.
Home + Lock Screen widget; AddNote App Intent in Siri
ActivityKit (ActivityAttributes, ContentState) · Dynamic Island layouts (compact, minimal, expanded) · push-to-start Live Activities · BackgroundTasks (BGAppRefreshTask) · low-power mode and how it changes everything.
"Shared-note edit in progress" Live Activity driven by Vapor push
XCTest vs Swift Testing (@Test, #expect) · XCUITest · snapshot testing · xcodebuild + xcbeautify · GitHub Actions macos-14 runners · fastlane (gym, pilot, match) · App Store Connect API.
Commit-to-TestFlight pipeline on GitHub Actions
Capstone integration · code review · architectural decision records · the production-runbook.md · the interview-prep system-design pack · daily 30-minute instructor review.
Capstone integration week — everything from Phases I–III
App Store Connect metadata · screenshots (1290×2796 and friends) · App Privacy · App Review (the actually-enforced guidelines) · TestFlight external beta · expedited review · chaos drills · the postmortem.
Offline-First Cross-Device Productivity Suite — TestFlight × 5 regions
§ V · The Toolchain
Swift the language is open-source. Vapor and the toolchain run on Linux. Where Apple's stack is the only path — SwiftUI, SwiftData, CloudKit, StoreKit, App Review — we name the trade explicitly. No proprietary IDE plugins are required.
§ VI · Skills You Will Carry
By the end of Week 24, you can do each of the following — credibly, on a real device, in front of a real reviewer.
Sendable, actor isolation, @MainActor, and structured task cancellation.@State, @Observable, @Environment, and @Bindable — and defend the choice in code review.async/await + AsyncSequence, with back-pressure intuition.NavigationStack + NavigationSplitView graph that survives state restoration, deep links, and universal links.§ VII · The Capstone
Week 24 closes a six-week capstone — the kind a real product team would scope across a quarter. Architecture diagram, public TestFlight in five regions, signed StoreKit subscription, Live Activity from a real-time push, chaos-drill postmortem.
Capstone Brief
A SwiftUI productivity suite running on iPhone, iPad, and Mac with a watchOS companion and a visionOS window, backed by a Vapor service on Linux. The system must work fully offline, sync across devices over CloudKit (with the Vapor backend as a fallback), monetise via a StoreKit 2 subscription validated server-side, expose App Intents to Shortcuts and Siri, render Widgets on the Home and Lock Screen, drive a Live Activity from a real-time event, and survive a documented chaos drill.
production-runbook.md another engineer can read at 3 AM, plus a five-minute walkthrough video.§ VIII · Getting Started
The first six weeks need nothing more than a terminal and the open-source Swift toolchain — Linux, macOS, or Windows + WSL2 all work. The Mac, Xcode, and Apple Developer Program turn on later, when the schedule demands them.
# 1. Clone the curriculum repository git clone https://github.com/CODE-CRUNCH-WORLDWIDE/C20-CRUNCH-SWIFT.git cd C20-CRUNCH-SWIFT # 2. Verify the Swift toolchain (Linux / macOS / WSL2) swift --version # expect Swift 6.x swift package init --type executable # sanity-check SwiftPM # 3. Open Week 1 README and begin $EDITOR curriculum/week-01-swift-language/README.md # Note: Weeks 1–6 are Linux-friendly Vapor + Swift. # From Week 7, install Xcode 16+ on a Mac (free, Mac App Store). # The iOS Simulator covers everything until Week 15.
Need the full hardware reality, prereq map, or pre/post-track diagram? See the README.
§ IX · Frequently Asked
Not for Weeks 1–6. Swift the language and the Vapor backend run on Linux, macOS, or Windows + WSL2 with the open-source toolchain from swift.org. From Week 7 onward you need a Mac — Apple Silicon strongly recommended (M1 or newer), 16 GB RAM realistic minimum — with Xcode 16+ installed free from the Mac App Store.
Only from Week 15, when we deploy to a physical iPhone or iPad for device-only features (camera, ARKit, BLE, real-device push, Live Activities on a physical Lock Screen) and for TestFlight and App Review in Phase 4. Phases 1 and 2 use the iOS Simulator, which is bundled with Xcode and free. We give two weeks of lead time so the $99/yr membership lands when the schedule needs it, not on day 1.
If you want to ship to iPhone, iPad, Mac, Apple Watch, and Vision Pro from one Swift codebase — take C20. If you want to ship to the Android ecosystem with Jetpack Compose — take C21 (Crunch Droid). They overlap on architecture (MVVM, unidirectional state, offline-first sync) and diverge on every platform API. Many graduates do both in sequence — that is Pathway B in the Crunch Labs Charter.
They are siblings. C20 owns Swift, SwiftUI, and the Apple platforms; C21 owns Kotlin, Jetpack Compose, and Android. The architectural spine — typed state, declarative UI, offline-first sync, server-side validation — is intentionally parallel so the second track is cheaper to take. Pick one to start. Many engineers take both, in sequence, not in parallel.
Yes. Vapor 4 on Linux is production-grade — Postgres via Fluent, structured logging via swift-log, OpenTelemetry export, and a Dockerized integration test. We use it because (a) it gives engineers without a Mac six real weeks of Swift work, and (b) sharing a SwiftPM Models package between server and SwiftUI client is the move that pays for the rest of the track. If your capstone outgrows Vapor, C16 (Web Backend) and C17 (Python Advanced) deepen the server side.
Both. Week 11 has you implement the same feature in plain SwiftUI + @Observable MVVM and in The Composable Architecture, then write an ADR defending the choice. Plain SwiftUI is correct for small surfaces; MVVM is the discipline most teams reach for; TCA earns its complexity on large reducer-heavy domains. The skill is not "knowing TCA" — it is choosing deliberately and being able to defend the choice on a senior-interview whiteboard.
§ X · Begin
Open the repository. Read Week 1. The simulator is free.