[gwdp]

Why

Let serve-sim start the Simulator and app while Appium is being prepared.

How

• Select Xcode and the Simulator once, then use the shared startup path. Check the egress guard before install/launch and wait for Appium before reporting the session.
• Appium still handles later app actions. Existing prepared workflows and Android keep their current path.
• Stop controller setup when Simulator startup fails; drain owned commands and preserve the first error.
• Surviving callers retry a canceled shared FFmpeg install together.

Release compatible serve-sim, deploy the worker, then enable the new workflow inputs.

Test Plan

• Codex rebased onto main at d0cb5a2d6, preserving preview privacy/CORS settings and idle-timeout coverage. All 260 focused tests, typecheck, changed-file lint and formatting pass locally, including two new privacy-forwarding regressions. CI passes on 9c145a4, and the Devin review of that head reported no new findings.
• Earlier local launch E2E passed: Universe-generated steps through build-tools download/install/start to pinned serve-sim on a real iOS Simulator. Verified one app start, arguments and deep link. Cloud calls used loopback adapters. Hosted Appium runs on the current head remain pending; the hosted Argent QA of [build-tools] Let serve-sim start the iOS Simulator for Argent #4602 does not cover the Appium path.

Cold startup benchmark

Session	Main median	Stack median	Median paired saving
appium	48.34s	34.29s	11.64s (25.4%)

Codex measured four alternating pairs per type on an initialized iPhone 17 Pro Simulator (iOS 26.4, Tart 6 CPU / 8 GiB), starting shut down with the app absent and packages cached. Timing runs from worker entry to local session reporting, using real controllers and native boot/install/launch with loopback cloud adapters.

This compares the completed startup stack e0b7462 against main 4aca8b1, with the same pinned local serve-sim #260 build; it does not isolate this PR's contribution. Hosted dispatch and first browser frame were not measured.

Savings are the median of paired differences, not the difference between the two arm medians. All four pairs were faster, by 10.53–16.61s. Appium timing ends after server readiness; WDA session creation was not measured.

Authorship and LLM use

Gabe wrote the initial implementation and guided the design. Codex implemented and split the changes. AI review led to fixes for startup order and cleanup. Gabe reviewed the final diff after the rebase, including the conflict resolution, and can answer questions.

Generated with T3 Code, using Codex and Claude Code.

[codecov]

Codecov Report

❌ Patch coverage is 94.28571% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 75.29%. Comparing base (d0cb5a2) to head (9c145a4).

Files with missing lines	Patch %	Lines
...ls/src/steps/functions/startAppiumRemoteSession.ts	95.84%	4 Missing ⚠️
...ld-tools/src/steps/utils/remoteDeviceRunSession.ts	91.67%	3 Missing ⚠️
...ges/build-tools/src/steps/utils/preinstalledWda.ts	87.50%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4603      +/-   ##
==========================================
+ Coverage   75.25%   75.29%   +0.04%     
==========================================
  Files        1053     1053              
  Lines       52045    52148     +103     
  Branches    11357    11387      +30     
==========================================
+ Hits        39162    39260      +98     
- Misses      11895    11900       +5     
  Partials      988      988              

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[gwdp]

Codex rebased #4603 onto current main d0cb5a2d6, including merged #4602. New head: 9c145a490.

Resolved the conflicts by retaining main’s preview privacy, frame-ancestor/CORS settings and idle-timeout test coverage alongside Appium startup and failure cleanup. Added two focused tests for forwarding those preview settings on prepared and consolidated startup paths; both reject the missing-forwarding resolution. All 260 focused tests, typecheck, changed-file lint and formatting pass. No hosted Appium or device run was performed for this rebase; fresh CI and Devin review are pending. Upper stack branches were left unchanged.

— Codex

[gwdp]

/devin review

Please review rebased head 9c145a490, especially preview privacy/CORS forwarding, idle-timeout compatibility, startup error propagation and shared FFmpeg ownership. The worker targets current main after merged #4602.

— Codex

[devin-ai-integration]

Starting Devin Review.

[github-actions]

✅ Thank you for adding a changeset!