scripts/dev-desktop.mjs fails on Windows: spawnSync npm ENOENT

[freetag369]

Environment

• Windows 11 (10.0.26200)
• Node v22.23.1, npm 10.9.8
• repo @ 872f363

Symptom

node scripts/dev-desktop.mjs (the one-command dev flow) dies immediately on the first step:

Error: spawnSync npm ENOENT

Cause

The script makes a few POSIX assumptions:

1. execFileSync("npm", ...) (scripts/dev-desktop.mjs lines 82 and 97) — on Windows npm is npm.cmd, and .cmd files cannot be spawned without shell: true (or resolving the full npm.cmd path explicitly).
2. run() spawns node_modules/.bin/<tool> directly (line 28) — on Windows those are .cmd shims too, so vite and electron-forge hit the same ENOENT even once (1) is fixed.
3. Teardown signals the process group with process.kill(-child.pid, "SIGTERM") under detached: true (lines 28 and 44) — negative-PID process-group signalling does not exist on Windows; tearing down the tree there needs something like taskkill /pid <pid> /T.
4. Minor but related: the apps/cli build script ends with chmod +x dist/index.js, which fails on Windows (after esbuild has already produced the bundle, so the output itself is fine).

Workaround

Start the pieces manually, which works fine:

1. npm run build --workspace=@diffusionstudio/cli
2. run Vite in apps/web
3. electron-forge start in apps/desktop

With the CLI handshake fix for Windows named pipes (submitted separately as a PR), the full dapi mount → capture → render flow then works on Windows.

Happy to follow up with a PR making dev-desktop.mjs Windows-aware if you'd take one — it's a slightly bigger change than the handshake fix, so I've kept it as a report for now.

🤖 Generated with Claude Code