Install fails on Apple Silicon: npx breaks on sharp source build; pnpm can't resolve transitive mobilecli

[deividasstr]

Summary

On Apple Silicon macOS, neither documented-ish install path works out of the box — and they fail for different reasons:

• npx / npm fails during install: a transitive sharp falls back to a source build that errors out, so the server never starts.
• pnpm dlx installs and starts fine, but the server then throws mobilecli is not available or not working properly on the first device call, because under pnpm's strict node_modules the binary isn't where the resolver looks.

The net effect is that there's no clean install path on Apple Silicon: one tool breaks on sharp, the other on mobilecli.

Environment

@mobilenext/mobile-mcp	0.0.59
mobilecli (transitive, via mobilewright)	0.3.79
sharp (transitive)	0.34.5
OS	macOS 26.4.1, Apple Silicon (arm64)
Node	v24.8.0
npm	11.6.0
pnpm	10.15.1

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Path A — npx / npm: sharp source build fails

$ npm install @mobilenext/mobile-mcp@latest
npm error code 1
npm error path .../node_modules/sharp
npm error command sh -c node install/check.js || npm run build
npm error > sharp@0.34.5 build
npm error sharp: Attempting to build from source via node-gyp
npm error sharp: See https://sharp.pixelplumbing.com/install#building-from-source
npm error sharp: Please add node-addon-api to your dependencies

The platform prebuilt that should avoid the source build is not installed:

$ ls node_modules/@img/
ls: node_modules/@img/: No such file or directory   # @img/sharp-darwin-arm64 missing
$ npm config get omit
                                                     # empty — optional deps are NOT opted out

So npm (11.6.0) does not install @img/sharp-darwin-arm64, sharp falls back to a node-gyp source build, and the whole install (and therefore npx -y @mobilenext/mobile-mcp@latest) hard-fails. This appears to be the well-known npm optional-dependencies resolution bug, but the result is that the documented npx install does not work on Apple Silicon.

Note: with --ignore-scripts the install completes and mobilecli is correctly hoisted to the top level — i.e. Path A's only blocker is sharp:

$ npm install --ignore-scripts @mobilenext/mobile-mcp@latest   # exit 0
$ ls node_modules/mobilecli/bin/mobilecli-darwin-arm64          # present ✓

---

Path B — pnpm dlx: mobilecli is not available

pnpm installs sharp from its prebuilt fine, so the server starts. But the first tool call fails:

mobilecli is not available or not working properly. Please review the documentation
at https://github.com/mobile-next/mobile-mcp/wiki for installation instructions

Root cause

mobilecli is not a direct dependency of @mobilenext/mobile-mcp — it's pulled in transitively via mobilewright. src/mobilecli.ts (getMobilecliPath) resolves the binary with a manual node_modules path join off __filename, not require.resolve:

// after the MOBILECLI_PATH env check:
const mobilecliPath = join(lastNodeModulesPath, "mobilecli", "bin", binaryName);
if (existsSync(mobilecliPath)) { return mobilecliPath; }

• Under npm's flat/hoisted layout, the transitive mobilecli lands at the top-level node_modules/mobilecli, so the join resolves. ✅ (This is why most users — npx on Intel/Linux where sharp's prebuilt installs — never see this.)
• Under pnpm's strict, symlinked layout, mobilecli lives only in the virtual store and is symlinked under mobilewright's subtree — never as a sibling of @mobilenext/mobile-mcp. The manual join (which doesn't follow pnpm's structure, unlike require.resolve) misses it, the version check throws, and the server reports "mobilecli is not available".

Verified the binary is present-but-unreachable in a pnpm dlx tree:

# .pnpm/mobilecli@0.3.79/.../bin/mobilecli-darwin-arm64  → exists and runs ('mobilecli version 0.3.79')
# .pnpm/@mobilenext+mobile-mcp@0.0.59/node_modules/      → mobilewright, zod, express… but NO mobilecli sibling

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Why this is an Apple-Silicon trap

The two failures compound: on Apple Silicon you can't use npx (sharp source build fails), so you reach for pnpm — which then can't resolve mobilecli. There's no out-of-the-box combination that works.

Suggested fixes

1. Declare mobilecli as a direct dependency of @mobilenext/mobile-mcp. Then pnpm symlinks it as a sibling and the existing path-join resolves (npm already hoists it). This is the smallest fix for Path B.
2. Resolve via require.resolve("mobilecli/package.json") instead of hand-rolling the node_modules path — robust across npm/pnpm/yarn layouts (still needs (1) so it's resolvable under pnpm).
3. Document MOBILECLI_PATH as a supported escape hatch in the README/wiki (it's honored first, but undocumented).
4. Path A: ensure the @img/sharp-<platform> prebuilt installs on Node 24 / npm 11 (pin a sharp with working prebuilts, or add node-addon-api), or document that pnpm is required and why.

Current workaround

Install the mobilecli binary out-of-band and point MOBILECLI_PATH at it; the server then skips its broken lookup and works under pnpm dlx.

[coderabbitai]

🔗 Related PRs

#241 - feat: move iphone-simulator calls to use mobilecli binary [merged]
#273 - feat: support remote devices [merged]
#316 - fix: update mobilecli binary path after package rename [merged]
#325 - feat: added 'list crashes' tool, replaced use of WebdriverAgent with iOS Device Kit on Simulator [merged]

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