How do I install the Eas Prebuild Check skill?

Run npx skillmds@latest add etanhey/eas-prebuild-check in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

What does the Eas Prebuild Check skill do?

Validate Expo iOS/Android sync before first EAS build. Triggers: eas build, prebuild, credentials. It is listed under Coding & Dev Tools on SkillMD.

Is Eas Prebuild Check safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Eas Prebuild Check?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Eas Prebuild Check free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Eas Prebuild Check?

EtanHey (@etanhey) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Eas Prebuild Check by etanhey — Agent Skill

Name: Eas Prebuild Check
Author: EtanHey

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.

#	Check	Prevents
1	`.easignore` exists and excludes `node_modules`, `.expo`, build dirs	2.1GB archive upload (real: TaskOwl first attempt)
2	Archive size estimate < 100MB	Concurrency waste, slow uploads
3	`eas-cli` is latest	Warnings + compat bugs
4	Bundle ID not a suspicious default (e.g., `com.yourname.fromtoday`)	Building under wrong App Store ID
5	`version`, `ios.buildNumber`, `android.versionCode` present and consistent	Apple Connect conflicts, re-submit blockers
6	At least 1 iOS device registered (for preview ad-hoc builds)	"No registered devices" blocker
7	iOS credentials (cert + provisioning profile) pre-synced	Mid-build Apple 2FA surprises
8	Android keystore ready (or EAS-managed configured)	Mid-build keystore prompt
9	Concurrency awareness (free vs paid tier)	Surprise serial queue

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

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:

Auto-fix	Skill does it?	Why
Write missing `.easignore`	✓ YES	New file, no data loss
Upgrade `eas-cli`	✓ YES (with user confirm)	Reversible via `npm install -g eas-cli@<prev>`
Change bundle ID	✗ NO	Requires human judgment (branding, App Store reservations)
Register devices	✗ NO	Needs physical device UDID
Configure credentials	✗ NO	Apple 2FA flow, user must be present
Bump version/buildNumber	✗ NO	Release decisions need human approval

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.

Eas Prebuild Check

File contents