• We have been developing all new features in Swift since 2018 - the choice that doesn’t need much explaining in 2023. The Objective-C part of the code is isolated well from the rest of the app and slowly but steadily declines in size.
• In 2022, we considered SwiftUI mature enough and started using it for all new UI code instead of the Texture framework we had used since 2018. The transition went smoothly since the layout in SwiftUI is based on similar principles as it was in Texture: it's declarative and relies on a container-based system for layout. The Texture framework was preferred over UIKit for the same reason before (and superior performance), but SwiftUI now has all the benefits and is also a first-party tool, actively supported and developed.
• In 2023 we switched to The Composable Architecture (TCA) for all our business-logic-related code. We have been using Redux-like architecture since 2019, when we decided to pursue this direction instead of the popular MVVM or Viper. It took us some time to adjust to it initially. Still, we enjoyed its benefits immensely: full transparency and control over state mutation, convenient testability, and composability that allows for immense scalability with minimal overhead. Initially, we used our in-house solution inspired by TCA, based on RxSwift. But since then, TCA evolved considerably and added many features that our solution was lacking, including support for modern first-party tools like async/await and Combine, so with the release of 1.0, we finally decided to make the switch. We keep it up to date, and as of Nov 2024, we use version 1.5 of TCA
• With the switch to SwiftUI and TCA in 2023, we adopted async/await and Combine instead of the previously used RxSwift. Naturally, it became replaced with first-party tools that provide the same or even superior functionality, which the rest of our stack integrates better with.
• We chose Swift Package Manager (SPM) over CocoaPods or Carthage back in 2020. Like the Swift language itself, it emerged somewhat limited. We watched patiently how it evolved until it received all the features that we needed, like the ability to have binary packages. With SPM, we could fully embrace modularization in our app, allowing us to easily create new internal modules and support any number of them.

Updated: Nov 2024