EAS Prebuild Check

Mission: catch the 9 pain points that wasted 2+ hours on TaskOwl Sprint 2 (April 8, 2026) BEFORE they waste any more time on future builds.

What it does

Runs 9 discrete checks against an Expo project, each reporting PASS / FAIL / WARN / SKIP / INFO with specific remediation commands.

Bonus warnings: P8 APNs key presence (if push enabled), active eas whoami matches app.json owner, managed vs bare workflow detection.

Remote commands and the CLI version query have bounded deadlines via timeout, gtimeout, or a macOS-compatible Perl alarm fallback that kills the child process group (exit 124 on timeout). If none is available, the check reports FAIL.

When to use

• Before the first EAS build on any new Expo project
• After major dependency changes (new native modules, Expo SDK bumps)
• When switching branches that touch app.json or native projects
• When inheriting someone else's Expo project
• Before a production build (to catch version drift)

Do NOT use for: debugging an in-progress build (use eas build:inspect), post-build validation, or issues unrelated to EAS submission.

Usage

# Run all checks for both platforms, preview profile (default)
/eas-prebuild-check

# Scope to iOS or Android
/eas-prebuild-check --platform ios
/eas-prebuild-check --platform android

# Auto-fix safe items (writes .easignore, prompts for eas-cli upgrade)
/eas-prebuild-check --fix

# Production profile (skips device-registration check)
/eas-prebuild-check --profile production

# Machine-readable JSON output for CI/CD
/eas-prebuild-check --json

Exit codes:

• 0 — all checks pass (or only WARN/INFO)
• 1 — at least one FAIL (do NOT run eas build)
• 2 — script error (missing eas-cli, not in an Expo project)

How it decides what's safe to auto-fix

--fix applies only LOSSLESS, REVERSIBLE changes:

Any file change triggers a diff preview + backup to .eas-prebuild-check.backup/.

Example output

# EAS Prebuild Check — taskowl-app
Profile: preview | Platform: both | Account: user@example.com

[1/9] .easignore exists ........................... ✗ FAIL
      node_modules not excluded. Estimated archive: 2.1 GB
      Fix: /eas-prebuild-check --fix
           (writes canonical .easignore from template)

[2/9] Archive size <100MB ......................... ⊘ SKIPPED
      Depends on [1]

[3/9] eas-cli up to date .......................... ⚠ WARN
      Installed: 17.2.1 | Latest: 18.5.0
      Fix: npm install -g eas-cli@latest

[4/9] Bundle ID consistency ....................... ⚠ WARN
      iOS: com.yuvalnir.fromtoday  ← suspicious scaffold default
      Android: com.yuvalnir.fromtoday
      Fix: edit app.json expo.ios.bundleIdentifier and expo.android.package

[5/9] Version sync ................................ ✓ OK
      version: 1.0.0 | iOS buildNumber: 1 | Android versionCode: 1

[6/9] iOS devices registered ...................... ✗ FAIL
      0 devices registered. Preview = ad-hoc distribution; needs ≥1 UDID.
      Fix: eas device:create

[7/9] iOS credentials synced ...................... ✗ FAIL
      No distribution certificate. No provisioning profile.
      Fix: eas credentials:configure -p ios --profile preview

[8/9] Android keystore ready ...................... ✓ OK
      EAS-managed keystore configured.

[9/9] Concurrency awareness ....................... ℹ INFO
      Account tier: FREE (1 concurrent build)
      iOS + Android together ≈ 40-60min queue time.

## Summary
  ✓ Passed: 2   ⚠ Warnings: 2   ✗ Failed: 3   ⊘ Skipped: 1   ℹ Info: 1

## Recommended order
  1. /eas-prebuild-check --fix  (auto-fixes 1, 3)
  2. Edit app.json bundle IDs (check 4)
  3. eas device:create            (check 6)
  4. eas credentials:configure -p ios --profile preview  (check 7)
  5. Re-run /eas-prebuild-check

  DO NOT run `eas build` until all FAIL items are resolved.

Files in this skill

eas-prebuild-check/
├── SKILL.md                    # This file
├── scripts/
│   ├── check.sh               # Main dispatcher (runs all checks)
│   └── checks/
│       ├── 01-easignore.sh
│       ├── 02-archive-size.sh
│       ├── 03-eas-cli-version.sh
│       ├── 04-bundle-id.sh
│       ├── 05-version-sync.sh
│       ├── 06-ios-devices.sh
│       ├── 07-ios-credentials.sh
│       ├── 08-android-keystore.sh
│       └── 09-concurrency.sh
└── templates/
    └── .easignore              # Canonical template

Related skills

• /pr-loop — run this BEFORE the PR loop when a PR touches native build config
• /never-fabricate — Read() the actual eas build output, don't trust "looks fine" from this skill alone
• the false-green-gate hook — enforces the order: run this skill, verify exit 0, THEN claim ready to build

Provenance

Built from TaskOwl Sprint 2 EAS build lessons (April 8, 2026), BrainLayer tags: eas-build, taskowl, skill-needed, lessons-learned. Plan: $ORCHESTRATOR_ROOT/docs.local/plans/eas-build-v1/README.md.