# Apple Sources Behind This Skill

Search for these by title in the Developer app or on developer.apple.com.
Sessions are cited by title and year.

| Source | Kind | Consult it for |
|--------|------|----------------|
| "Optimize SwiftUI performance with Instruments" (WWDC25) | Session | The SwiftUI Instrument workflow, the Cause and Effect Graph, Instruments 26 terminology |
| "Demystify SwiftUI performance" (WWDC23) | Session | Dependency fan-out, identity, and guidance for lists and tables |
| "Understanding and improving SwiftUI performance" | Xcode documentation article | Current lane names and remediation for long and frequent updates |
| "Understanding hangs in your app" | Xcode documentation article | Hang thresholds, the main run loop, triage |
| "Analyze hangs with Instruments" (WWDC23) | Session | Using the Hangs instrument on the main run loop |

Which one to open:
- A trace from Instruments 26 with SwiftUI lanes: the WWDC25 session.
- Rows re-rendering, ids churning, a list that will not diff: the WWDC23
  "Demystify" session.
- Deciding whether a problem is a long update or a frequent one: the SwiftUI
  performance article.
- A freeze where you first need to prove the main thread is blocked: the hangs
  article and the WWDC23 hangs session.