SwiftUI Performance with UIKit (SwiftUI)

Build the app core, lifecycle and navigation, in SwiftUI, and drop to UIKit only for the performance-critical surfaces such as infinite feeds. UIHostingConfiguration puts SwiftUI views inside recycled UITableView or UICollectionView cells.

Why not a UIKit shell anymore

The old pattern, a UIKit coordinator pushing UIHostingController-wrapped screens, still works and suits apps that support iOS 15 and earlier. Its cost: every UIHostingController creates its own SwiftUI environment, so environment values, styling, and shared data do not propagate between screens. From iOS 16, NavigationStack with a NavigationPath covers deep linking and state restoration in pure SwiftUI.

@main
struct ExamplesApp: App {
  @State private var path = NavigationPath()
  @State private var store = Store()

  var body: some Scene {
    WindowGroup {
      NavigationStack(path: $path) {
        HugeListView(items: store.items)
          .navigationDestination(for: Item.self) { item in /* details */ }
          .onOpenURL { url in /* parse and push */ }
      }
    }
  }
}

UIHostingConfiguration for huge lists

Where SwiftUI lists glitch, social timelines, calendar layouts, any effectively infinite collection, wrap a UITableView in a UIViewRepresentable and keep cell dequeuing. Each cell's contentConfiguration hosts a SwiftUI view.

struct HugeListView: UIViewRepresentable {
  let items: [Item]

  func makeUIView(context: Context) -> UITableView {
    let tableView = UITableView()
    tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
    tableView.dataSource = context.coordinator
    return tableView
  }

  func updateUIView(_ uiView: UITableView, context: Context) { uiView.reloadData() }
  func makeCoordinator() -> Coordinator { Coordinator(items: items) }

  final class Coordinator: NSObject, UITableViewDataSource {
    let items: [Item]
    init(items: [Item]) { self.items = items }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
      items.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
      let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
      cell.contentConfiguration = UIHostingConfiguration {
        ItemView(item: items[indexPath.row])
      }
      return cell
    }
  }
}

Gotcha: no NavigationLink inside cells

UIHostingConfiguration exists only for embedding SwiftUI in UICollectionView and UITableView cells. Do not put a NavigationLink inside one: handle selection in the coordinator and append the value to the NavigationStack path instead.