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+---
+name: electron-build
+description: "Electron desktop app builds: cross-compile for Windows on Linux and fix bundled Chromium DLL issues."
+version: 1.0.0
+author: Hermes Agent
+license: MIT
+metadata:
+  hermes:
+    tags: [electron, windows, cross-compile, nsis, exe, msi, wine, chromium, dll-fix, build]
+    related_skills: [hermes-desktop-build]
+---
+
+# Electron Build
+
+Two build/deploy concerns for Electron desktop apps: cross-compiling for Windows from Linux, and fixing bundled Chromium DLL issues on Windows.
+
+## Section 1: Cross-Compile Linux → Windows
+
+Build Windows exe/msi/installer from an Electron project on a Linux host.
+
+**When to use:** Building Electron apps for Windows users from a Linux CI/CD server.
+
+### Prerequisites
+
+- Node.js 18+ and npm
+- Disk space: **at least 300MB free** per build (electron binary ~115MB + app + NSIS output ~160MB)
+- `wine` for NSIS installer signing step (even without a certificate, makensis needs wine)
+
+### Install Wine
+
+```bash
+sudo dpkg --add-architecture i386
+sudo apt-get update
+sudo apt-get install -y wine32:i386 wine64
+```
+
+### Disable Code Signing (no certificate)
+
+```json
+"win": {
+  "target": ["nsis", "portable"],
+  "icon": "assets/icon.ico",
+  "signAndEditExecutable": false,
+  "sign": null
+}
+```
+
+### Build
+
+```bash
+npm run build:win
+# Output: dist/*.exe, dist/*.msi
+```
+
+### Full Build-to-Deploy Workflow (AtomK Desktop)
+
+```bash
+# 1. Version bump → branch → PR → merge (Gitea main is protected)
+cd /path/to/project
+npm version 3.9.XX --no-git-tag-version
+git checkout -b release/v3.9.XX
+git add package.json && git commit -m "build: bump version to 3.9.XX"
+git push origin release/v3.9.XX
+
+# 2. Create PR + merge via Gitea API (basic auth, token unreliable)
+python3 -c "
+import requests, base64
+auth = base64.b64encode(b'USER:PASS').decode()
+r = requests.post('https://gitea.HOST/api/v1/repos/OWNER/REPO/pulls',
+    headers={'Authorization': f'Basic {auth}', 'Content-Type': 'application/json'},
+    json={'title':'build: bump to X.XX','head':'release/v3.9.XX','base':'main'}, verify=False)
+pr = r.json()['number']
+requests.post(f'.../pulls/{pr}/merge', headers={'Authorization': f'Basic {auth}'}, json={'Do':'merge'}, verify=False)
+"
+
+# 3. Pull main + build
+git checkout main && git pull origin main
+rm -rf dist/
+NODE_OPTIONS=--max-old-space-size=4096 npm run build:win
+
+# 4. Upload to Tencent COS (Hong Kong region)
+source ~/.hermes/custom_services.env
+coscmd -b 9websclub-1251422183 -r ap-hongkong upload dist/*.exe desktop/
+coscmd -b 9websclub-1251422183 -r ap-hongkong upload dist/*.exe.blockmap desktop/
+
+# 5. Clean up
+git branch -d release/v3.9.XX
+git push origin --delete release/v3.9.XX
+```
+
+### Key Pitfalls
+
+1. **Disk space** — 300MB+ per build; clean old builds before new ones
+2. **Wine warnings** — wine32 display driver warnings are harmless for CLI usage
+3. **COS upload** — use `coscmd` for Tencent Cloud (configured via `~/.hermes/custom_services.env`), `aws s3` for AWS
+4. **Code signing** — without a certificate, set `signAndEditExecutable: false` and `sign: null`
+5. **Gitea protected branches** — `main` is usually protected; push to `release/vX.X.XX` branch instead, then create + merge PR via Gitea API. Use basic auth (username:password base64) — token may be expired.
+
+**See:** `references/electron-cross-compile.md` for full step-by-step, NSIS config, and upload procedures.
+
+## Section 2: Bundled Chromium DLL Fix on Windows
+
+When bundling Chromium inside an Electron app for CDP/browser automation, 3 GPU DLLs must be present or Chromium crashes silently on Windows.
+
+### Problem
+
+Electron apps bundling Chromium fail silently with no error output. Root cause: GPU-related DLLs were removed to reduce installer size, but Chromium requires them even with `--disable-gpu`.
+
+### Missing DLLs
+
+Copy these from a matching Chromium for Windows release:
+- `D3DCompiler_47.dll` (~4.9MB)
+- `libEGL.dll` (~494KB)
+- `libGLESv2.dll` (~8.2MB)
+
+Source: `https://storage.googleapis.com/chromium-browser-snapshots/Win/<build>/chrome-win.zip`
+
+### Key Insight
+
+**`--disable-gpu` is NOT sufficient.** Chromium still loads these DLLs at startup for basic rendering pipeline initialization.
+
+### Fix Steps
+
+1. Download matching Chromium version full archive
+2. Copy 3 DLLs to bundled chromium directory (e.g., `resources/chromium/`)
+3. Remove `--disable-gpu` flag from spawn args (now GPU works properly)
+4. Add `diagnoseBrowserSearch()` function: check registry paths, known paths, DLL presence
+5. Rebuild: `npm run build:win`
+
+### Verification
+
+```bash
+7z l dist/app-X.X.X-setup.exe | grep -E "D3DCompiler|libEGL|libGLESv2"
+```
+
+**See:** `references/electron-bundled-chromium-dll-fix.md` for full diagnosis and fix details.