iOS ETTrace Performance

Use this skill to capture a focused, symbolicated ETTrace profile from an iOS simulator app. Pair it with ../ios-debugger-agent/SKILL.md when the task also needs simulator build, install, launch, UI driving, logs, or screenshots.

Core Workflow

1. Pick one focused flow and write down the expected start and stop points.
2. Build the exact simulator app that will be installed and profiled.
3. Temporarily link ETTrace into that app target for simulator/debug profiling.
4. Collect UUID-matched dSYMs for the app executable and embedded dynamic frameworks.
5. Capture one launch or runtime trace.
6. Preserve the processed flamegraph JSON immediately after the run.
7. Analyze only the processed JSON and report the flow, artifacts, hotspots, and caveats.

Avoid broad "use the app for a while" captures. One trace should correspond to one user-visible flow.

Setup

Use a writable run folder for each profiling session: