NativeKeel README

NativeKeel

Health check for React Native and Expo apps. One command, no install, no account:

npx nativekeel

No terminal handy? Paste your package.json at nativekeel.com/check: the same dependency checks and upgrade plan, run in your browser.

What's new in 0.1.87: when a report has a store or end-of-support deadline (Play target SDK, 16 KB pages, Xcode 27 UIScene, unsupported React Native or Expo, New Architecture off), it ends with one line on where to ask if your team can't fit the upgrade in time. 0.1.86: a page for the React Native 0.77+ error "RCTEventEmitter.receiveEvent() ... has not been registered as callable" with the AppDelegate fix for Objective-C and Swift (nativekeel.com/fix/rcteventemitter-receiveevent-not-registered), linked from the finding that detects it. 0.1.85: the AppDelegate-window crash finding links to a new page listing each affected library and its fix (nativekeel.com/fix/appdelegate-window-unrecognized-selector); reports point to Expert help instead of the old pricing link. 0.1.84: nativekeel.com/check: paste a package.json and get the dependency checks and upgrade plan in your browser, with the same rules as the CLI. 0.1.83: the GitHub Action can keep one comment on each pull request up to date with the findings that pull request adds or fixes (pr-comment: true). verify no longer reports unchanged committed signing keys and passwords as new. 0.1.82: npx nativekeel bundle new.map --base old.map compares two release builds: which packages were added or removed, which grew, and which started being bundled twice (one import _ from "lodash" showed up as +107 KB). Also in the MCP tool measure_bundle. 0.1.81: the bundle measurement reaches the rest of the report and AI agents: lodash and moment findings say how many bytes they really take in your release bundle (or that they are not in it), and the MCP tool measure_bundle returns the per-package breakdown. 0.1.80: npx nativekeel bundle: the release JavaScript bundle measured from its source map, per package, including packages bundled twice. Works with Hermes bytecode maps; nothing is built or run. 0.1.79: fewer false alarms: push-notification and invitation tokens are no longer reported as unencrypted auth tokens, even when the storage key is a constant, and large JSON required inside a function is described as bundled but evaluated only when used. 0.1.78: OTA updates: a note when expo-updates relies on a hand-written runtime version or the appVersion policy (59 of 871 apps), and react-native-code-push now says that App Center is gone and Microsoft archived its CodePush server. 0.1.77: iOS file sharing that puts an unencrypted MMKV, expo-sqlite or Realm database in the Files app and Finder. 0.1.76: biometric unlocks that only check a yes/no in JavaScript, with no secret bound to Face ID/Touch ID/fingerprint (41 of 871 apps, wallets among them); apps that bind a key in JS or native code are not flagged. 0.1.75: placeholder text is checked for contrast too (placeholderTextColor against the input or the view behind it): 226 placeholders in 55 of 871 apps. 0.1.74: large JSON imported into the JavaScript bundle (all translations up front, Lottie JSON that could be a .lottie asset) in 19 of 871 apps, and a note on touchables without accessibilityRole. 0.1.73: text contrast: where a Text color and the background behind it are both literal colors in the code, pairs below WCAG 2.2 AA (4.5:1, or 3:1 for large text) are reported. Found in 180 of 871 open-source apps. 0.1.72: buttons whose tappable area is certainly under 44×44 points (explicit size or a bare small icon) and have no hitSlop: 209 of 871 open-source apps. 0.1.71: accessibility checks: icon-only buttons without a label, unlabeled text fields, app-wide text scaling turned off, and Text.defaultProps that React 19 ignores. On 871 open-source apps, 282 have at least one unlabeled icon button. 0.1.70: in nativekeel improve, AI keys shipped in the bundle are contained like other exposed credentials, signing keys get signing-specific steps, and upgrade work has its own group. 0.1.69: a package.json entry that is not a valid package name (a typo or a workspace alias) is skipped with a warning instead of stopping the scan; the improvement plan gives New Architecture steps for apps before 0.76. 0.1.68: nativekeel improve and MCP improve_app turn existing findings into a prioritized app improvement plan. Exposed credentials get containment steps; dependency usage and performance signals require context and verification. Static patterns do not establish measured speed or size savings. 0.1.67: the Codex plugin works again without configuration: Codex cannot pass environment variables to a plugin's server, so its boundary is your home folder (or only NATIVEKEEL_MCP_ROOTS on a server you configure yourself). 0.1.66: six native Android source checks: archive paths reaching file writes, incoming nested Intent launches, caller-selected WebView URLs, Intent text reaching SQL, and caller-selected file reads/writes. Explicit exported entry points are correlated with Java/Kotlin source and literal Gradle namespaces; findings state OS protections, prerequisites and verification steps. 0.1.65: npx nativekeel security and MCP security_audit: a focused review of data exposure, account access and code execution risks. Eight new checks trace credentials into telemetry/URLs, external input into eval/SQL, unsafe OAuth settings and broad private FileProvider paths. Findings show evidence, attacker prerequisites, a fix and a verification step; zero findings never certifies security. 0.1.64: stricter MCP file boundaries, validated dependency names, and malware stop warnings preserved across scan, plan, error and verify tools. New checks flag Firebase writes guarded only by sign-in and unconditional Supabase row policies. These are source findings, not proof of deployed exploitability. Plugin servers now require explicit NATIVEKEEL_MCP_ROOTS. 0.1.63: a Codex plugin (codex plugin marketplace add AlicanAkyol/nativekeel) with the MCP server and the same skill as the Claude Code plugin. 0.1.62: npx nativekeel verify and the verify_upgrade MCP tool: after an upgrade, what got fixed and what is new compared with the last commit; exits 1 on new critical or high findings. 0.1.61: npx nativekeel explain "<error>" and the explain_error MCP tool: what a build, launch, crash or store-review error means, the fix, and where your project is affected. 0.1.59: the upgrade plan lists what changes in the next React Native and Expo versions in your own code. 0.1.57: a Claude Code plugin (claude plugin marketplace add AlicanAkyol/nativekeel) that adds the MCP server and tells Claude when to use it, one-click install for Cursor and VS Code. 0.1.56: warns before you run a project with planted malware (a VS Code task that runs on folder open, code hidden after a long run of spaces in babel.config.js, JavaScript disguised as a font), the trick behind fake job tests sent to developers. Found in 4 open-source repositories during our weekly scan. 0.1.55: listed in the official MCP Registry (io.github.AlicanAkyol/nativekeel). Recent releases added a Start here list in every report, hacking risks mapped to OWASP MASVS, crash and performance checks. Every check is tuned on 850+ open-source React Native and Expo apps, with recently updated ones added every week, to keep false alarms out (what we found in them). All releases →

Summary  4 critical · 4 high · 6 medium · 7 low
Security (OWASP MASVS)  crypto 1 · network 1 · code 1  ·  7 finding categories; not a compliance verdict

Start here
  1. Revoke the AWS access key ID in src/App.js:6 at the provider today.
  2. Set targetSdkVersion = 36 and compileSdkVersion = 36 in android/build.gradle.
  3. Replace @react-native-community/push-notification-ios: no New Architecture support, unmaintained.

Could someone steal data or abuse the app?

npx nativekeel security . --html security.html --fail-on high

Review secrets, credential leaks, backend access rules, unsafe code execution, transport and dependency risks in one report. New flow/configuration findings show where the input enters, where it is used, what an attacker would need, and how to verify the fix. --offline keeps the scan offline and skips online advisory checks. No source code is uploaded.

This is source analysis, not a live attack or a security certificate. Security checks and scope · Mobile flow details · Native Android details.

What it checks

Upgrade

• Is your React Native / Expo version still supported? React Native supports the latest three minors; in Expo projects React Native moves with the SDK.
• Can you upgrade at all? The legacy architecture was removed in 0.82. If the New Architecture is off (it is off by default before 0.76), you are stuck at 0.81.
• Which packages block the upgrade? Native modules without New Architecture support (cross-checked with the package's own codegen spec), unmaintained or with no release in years, with verified alternatives and renamed packages. Library versions for each step come from the libraries' own compatibility tables.
• Which packages might be unused? Installed packages with no import, native reference, requirement or patch found. Listed for review, not automatic removal: dynamic and generated usage can hide from a static scan.

Store

• Will Google Play and the App Store accept your next build? targetSdk, permissions Google Play restricts (photo/video, all files, background location, app installs, SMS), 16 KB memory pages (it also opens your built APK/AAB and checks every native library), the iOS privacy manifest and SDKs too old to have one, missing Info.plist usage descriptions, sign-up without account deletion, social login without Sign in with Apple, and release builds signed with the debug key.

Crashes

• Will it crash at runtime? packages off the versions your Expo SDK expects, release builds that still point at a development server, native libraries that need a newer React Native, Reanimated without its Babel plugin or react-native-worklets, mixed @react-native-firebase/* or @react-navigation/* majors, a second copy of React or React Native inside a dependency, Kotlin modules that cannot load through the New Architecture interop layer, AppDelegate setups that crash in Release, camera/photos/location access without the Info.plist text iOS requires, imports of APIs removed from React Native core (AsyncStorage, Picker, ViewPropTypes, …) or deprecated for removal (ImageBackground, SafeAreaView), and traps learned from real upgrades.

Security, grouped by OWASP MASVS

• Secrets in the app or the repo: AWS, Stripe, OpenAI, Anthropic, GitHub, Slack, SendGrid, Twilio, Shopify, Google OAuth and Supabase service_role keys, private keys, .env values compiled into the bundle, Expo extra/EXPO_PUBLIC_/eas.json secrets, signing keys and passwords.
• Data on the device: iOS file sharing (UIFileSharingEnabled) that exposes an unencrypted MMKV, expo-sqlite or Realm database (they live in Documents by default on iOS), passwords that flow into crash reports, analytics, databases or plain AsyncStorage (followed through variables), auth tokens in unencrypted storage, Android backups that copy them.
• Network: TLS certificate checks turned off in native code, cleartext HTTP, NSAllowsArbitraryLoads, plain-HTTP API calls, user-installed CAs in release.
• Backend rules: Firebase Realtime Database, Firestore and Storage rules open to anyone or in test mode; Supabase tables created without row level security; sign-in-only Firebase write rules and unconditional Supabase UPDATE/DELETE policies without row ownership checks. Policy findings include file/line evidence and explain deployment/grant assumptions.
• Authentication: biometric prompts (Face ID, Touch ID, fingerprint) whose success is only a yes/no in JavaScript, with no secret bound to biometrics in the keychain/keystore, in JS or native code: the prompt guards the screen, not the data.
• Cryptography: hardcoded encryption keys, MD5/SHA-1 on passwords, ECB mode, Math.random for nonces and salts.
• Platform: WebViews that read local files or load HTTP into HTTPS, Android components any app can start, unverified deep links and the template myapp:// URL scheme.
• Dependencies and reverse engineering: known vulnerabilities in the exact versions you ship (GitHub Advisory Database), source maps in the app, Hermes or R8 off.

These are static checks: they catch the common, detectable mistakes, not everything a penetration test of the running app and backend would.

Performance

• What is your release bundle actually made of? npx nativekeel bundle reads the source map a release build already wrote (Android: android/app/build/generated/sourcemaps/react/release/, Expo: npx expo export --dump-sourcemap) and measures how much of the shipped code is your app and each package, and which packages are bundled twice. --base old.map compares two builds: what was added, removed or grew. Nothing is built or run; the normal scan picks the map up too.
• Where should you investigate performance? Nested list patterns, JavaScript animation settings, source logging calls, root lodash/moment imports, referenced images over 500 KB, JSON over 300 KB imported into the JavaScript bundle (every language's translations, Lottie animations), and selector allocation patterns. Confirm the actual components, release output and runtime behavior before changing them; these checks do not measure frame rate, startup time or savings. Accessibility
• Can everyone use it? Icon-only buttons with no accessibility label (VoiceOver and TalkBack say just "button"), buttons smaller than 44×44 with no hitSlop, text and placeholders whose color and background (both set in the code) fall below WCAG contrast, text fields with no label or placeholder, and text scaling turned off for the whole app. Text.defaultProps is flagged too: React 19 (React Native 0.78+) ignores it in JSX, so app-wide fonts and font-scaling limits silently stop applying. Only React Native's own touchables and inputs are checked; custom components, focus order and color contrast still need a test with a screen reader.

App improvement review

npx nativekeel improve /path/to/app --offline
npx nativekeel improve /path/to/app --offline --out IMPROVE.md

Existing security, stability, performance, store and dependency findings become an ordered plan with reasons, applicability conditions, actions, verification and recovery. Exposed credentials get containment instructions. Apparently unused dependencies are review candidates: direct, transitive, dynamic, native and generated consumers must be considered before removal. Performance signals are not measurements.

Use --json for structured output or MCP improve_app. Malware findings block execution-dependent actions. Unknown runtime, backend, accessibility and reliability coverage stays explicit. This adds a decision layer over existing checks, not new vulnerability detectors. See scope and next modules.

Usage

npx nativekeel [path]              # report
npx nativekeel plan --out UPGRADE.md   # step-by-step upgrade plan
npx nativekeel --html report.html  # shareable HTML report
npx nativekeel --markdown pr.md    # summary for a pull request comment
npx nativekeel --sarif nk.sarif    # GitHub code scanning
npx nativekeel --json              # machine-readable output
npx nativekeel --fail-on high      # exit 1 on high or critical (default: critical)
npx nativekeel --offline           # no network at all, local checks only
npx nativekeel --verbose           # list every outdated package

Everything is free. The scan exits with code 1 when it finds a critical issue, so it can gate CI.

Upgrade plan

nativekeel plan turns the report into ordered work: stop leaks, set up a safety net of UI flows, fix crash risks, meet store deadlines, close security gaps, replace blocking packages, switch on the New Architecture at the right point, then upgrade React Native (or the Expo SDK) in small, reviewable hops with links to the Upgrade Helper diffs and the library versions each hop needs. Performance fixes and routine updates come last.

GitHub Action

# .github/workflows/nativekeel.yml
name: NativeKeel
on: [pull_request]
permissions:
  contents: read
  security-events: write   # only needed with sarif: true
jobs:
  health:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v7
      - uses: actions/setup-node@v7
        with: { node-version: 20 }
      - run: npm ci
      - uses: AlicanAkyol/nativekeel@v0
        with:
          fail-on: critical
          baseline: .nativekeel-baseline.json   # optional
          sarif: true                           # findings inline in the PR

The report is added to the job summary. To also keep one comment on each pull request up to date with what that pull request adds or fixes, give the job pull-requests: write and set pr-comment: true:

permissions:
  contents: read
  pull-requests: write
# …
      - uses: AlicanAkyol/nativekeel@v0
        with:
          pr-comment: true

The comment compares the pull request with its base commit (no code runs) and is edited in place on every push, not repeated. Pull requests from forks get a read-only token, so they get the job summary only.

With a baseline, only findings that are new since the baseline fail the build:

npx nativekeel --save-baseline .nativekeel-baseline.json   # commit this file

Use with AI coding agents (MCP)

Let Claude Code, Codex, Cursor, VS Code or any MCP client ask NativeKeel what is wrong with a project, how to upgrade it, and which version of a library works with your React Native version, instead of guessing. With it installed, the agent checks the project before it upgrades React Native or Expo, adds a native library, prepares a store release, or runs a project you did not write.

Claude Code (plugin: the MCP server plus a skill that tells Claude when to use it):

claude plugin marketplace add AlicanAkyol/nativekeel
claude plugin install nativekeel@nativekeel

Or the MCP server alone: claude mcp add nativekeel -- npx -y nativekeel@latest mcp

Codex (plugin: the MCP server plus the same skill):

codex plugin marketplace add AlicanAkyol/nativekeel
codex plugin add nativekeel@nativekeel

Or only the MCP server, in ~/.codex/config.toml:

[mcp_servers.nativekeel]
command = "npx"
args = ["-y", "nativekeel@latest", "mcp"]

Any other agent, no MCP needed: add this line to your project's AGENTS.md or CLAUDE.md:

Before upgrading React Native or Expo, adding a native library, or preparing a store release, run `npx -y nativekeel@latest --json` and fix the critical and high findings first.

Also listed in the official MCP Registry as io.github.AlicanAkyol/nativekeel.

Tools: scan_project (findings with file:line and fixes), measure_bundle (what the release bundle is made of, from its source map), upgrade_plan (ordered steps), check_library (latest version, New Architecture support, maintenance, the range that works with a given React Native version, known traps) explain_error (what a build, launch, crash or store-review error means, the fix, and where this project is affected) and verify_upgrade (after an upgrade: what got fixed and what is new compared with the last commit). Without MCP: npx nativekeel explain "<error>" --path . and npx nativekeel verify. The server is read-only and only scans folders under the directory it was started in, plus NATIVEKEEL_MCP_ROOTS (set it when your client starts servers from another folder). Results omit source files and non-package project names. Common instruction-like patterns are filtered, but this is not a complete prompt-injection defense. Malware findings stop upgrade plans; verify_upgrade.ok means no new serious findings, while safety.blocked separately reports current malware. Servers started inside a plugin folder (Codex) use your home folder as the boundary, or only NATIVEKEEL_MCP_ROOTS when it is set. See SECURITY.md.

Reports for clients

Agencies can put their own name on the HTML report: npx nativekeel plan --html plan.html --brand "Acme Mobile".

Why you can run this on private code

• Your code never leaves your machine. The only requests are package-name lookups on npm and React Native Directory, and one request to npm's advisory endpoint with the names and exact versions of your runtime dependencies (what npm audit sends). In Expo projects without node_modules, one request to unpkg for the versions your Expo SDK expects (only the expo version is sent). --offline makes none; a test traps fetch to prove it.
• Zero dependencies, no install scripts. Only Node.js built-ins.
• Read-only. It never changes your project.
• Safe on untrusted projects. It never runs project code, and a repository's own git config cannot make the scan run a command.
• Secrets are always masked in every output.
• Verifiable releases. Published with npm provenance from GitHub Actions: npm audit signatures.

Details and vulnerability reporting: SECURITY.md. Wrong or missed finding? Tell us, no code needed.

Expert help

The tool is free and stays free. If your team would rather hand an upgrade over, the maintainer takes on a few projects at a time: send your report to hello@nativekeel.com. How it works.

License

MIT