Xcode 26.4 Scope Guides , The Editor Feature You’ll Wonder How You Lived Without

A quiet addition that makes deeply nested Swift code dramatically easier to read and it’s off by default.

Xcode 26.4 shipped a small but impactful editor improvement: Scope Guides. They’re vertical lines that visually mark where each code block begins and ends and notably, they didn’t make it into the official release notes. Many developers may never discover them at all.

If you’ve ever lost track of which closing brace belongs to which block in a deeply nested reducer, closure chain, or async task group, this feature was built for exactly that situation.

How to enable it

1. Open Xcode Settings with Cmd + ,

2. Navigate to the Editing tab

3. Select the Display sub-tab

4.Find the Scope guides dropdown and choose your preferred mode

Active Only is the most practical choice for most workflows.It keeps the editor clean while surfacing scope context exactly when you need it, without overwhelming files with dense nesting like TCA reducers.

Where it makes a real difference

Consider a typical nested async pattern:

func syncUserData() async throws {
    try await withThrowingTaskGroup(of: Void.self) { group in
        for user in users {
            group.addTask {
                let data = try await fetchProfile(for: user)
                if data.needsSync {
                    try await upload(data)   // ← which scope are you in?
                }
            }
        }
    }
}

With Active Only, placing your cursor on the upload(data) line draws a single guide tracing back to its enclosing addTask block immediately confirming the scope without manually counting braces. The same applies to TCA reducers with multiple nested case branches, or any deeply nested SwiftUI view modifier chain.