App architecture
Build a practical understanding of app architecture from the underlying principles.
BUILD · 15 ARTICLES
iOS Engineering
Explore the structural and tooling decisions behind long-lived iOS apps, including architecture, state, dependencies, module boundaries, and build strategy.
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What this topic covers
UIKit & SwiftUI
Build a practical understanding of uikit & swiftui from the underlying principles.
Modules and builds
Build a practical understanding of modules and builds from the underlying principles.
Apple development tools
Build a practical understanding of apple development tools from the underlying principles.
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A guided path from fundamentals to the next step.
[iOS Architecture #1] iOS MVC and Why Massive View Controllers Exist
There’s a joke almost every iOS developer hears at least once.
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[iOS Architecture #8] Choosing an iOS Architecture
If you’ve followed this iOS architecture series this far, the options are all on the table: MVC, MVVM, MVP, VIPER, Clean Architecture, MV, and TCA.
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Why use RxSwift and Combine on iOS? Problems reactive programming solves
At some point while studying iOS development, you inevitably encounter RxSwift or Combine. They appear in nearly every job posting, but opening the code can be intimidating: unfamiliar syntax chains together map, flatMap, and sink. “Closures and…
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NSTimer Memory Leaks: 3 Causes of Retain Cycles and Fixes
Repeating NSTimer strongly retains its target, so the view controller is not released until invalidate(). This summarizes the cycle, block-based API, lifecycle invalidation, and weak proxy solutions.
Read article[iOS Architecture #10] Uber RIBs: Breaking Apps Down by Business Logic
RIBs split an app by business logic rather than screens. This article explains the premise of viewless components, why RIBs suit only very large organizations, and how they differ from VIPER.
Read article[iOS Architecture #9] ReactorKit: The Unidirectional Standard
ReactorKit is the framework that established unidirectional data flow as a standard for UIKit and RxSwift. This article explains the two roles, View and Reactor, why Mutation is needed as an intermediate step, and how it differs from TCA.
Read article[iOS Architecture #7] TCA and Unidirectional Data Flow
One name is impossible to miss in architecture discussions in the SwiftUI era: TCA (The Composable Architecture), created by Point-Free.
Read article[iOS Architecture #6] Clean Architecture Essentials
You often see “based on Clean Architecture” in job postings and technical blogs. But when you open the code, every team has a different interpretation. Some use UseCase, others do not, and Repository responsibilities vary as well.
Read articleiOS Coordinator Pattern: Moving Screen Transition Code Out of View Controllers
When building an iOS app, view controllers can gradually become bloated.
Read article[iOS Architecture #5] Why iOS VIPER Fell Out of Favor (RIBs)
Few patterns in iOS architecture inspire opinions as divided as VIPER.
Read article[iOS Architecture #4] MVP vs MVVM: Key Differences
One question comes up repeatedly in iOS architecture interviews.
Read articleIntroducing Layerz, a design tool for drawing iOS apps that work without code
Screens made with prototyping tools merely “look” convincing. Tapping a button only takes you to a prelinked screen; no data is actually saved, and nothing communicates with a server. So validating an idea ultimately required someone to write code.
Read articleDeclarative vs. Imperative: Understanding SwiftUI
The first line of every SwiftUI introduction inevitably mentions a “declarative framework.” React and Jetpack Compose also describe themselves as declarative.
Read article[iOS Architecture #3] Does SwiftUI Need ViewModels? A Complete Debate on MV Patterns
The iOS community has been debating a hot topic for years.
Read article[iOS Architecture #2] MVVM and Binding: Key Takeaways
In the previous article, we covered why Massive View Controllers emerge. Because a view controller serves as both View and Controller, all code with nowhere else to go ends up there.
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