Cross-platform support: Windows build target and CI release workflow

- Normalize watcher paths to forward slashes (Windows events use
  backslashes; all sync maps are '/'-keyed), path.delimiter for
  PATH/TEXINPUTS, dirname() instead of '/'-substring splits, bridge log
  in os.tmpdir()
- Platform-aware TeX search paths (TeX Live / MiKTeX on Windows),
  terminal shell default (COMSPEC/powershell), native window frame off
  macOS
- electron-builder: NSIS target + win icon + GitHub publish provider
- GitHub Actions workflow builds the Windows installer on tag push
  (node-pty needs MSVC — cannot cross-compile from macOS) and attaches
  it to the release

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

7 files changed, 96 insertions, 27 deletions

diff --git a/.github/workflows/release-windows.yml b/.github/workflows/release-windows.yml
new file mode 100644
index 0000000..fb557a5
--- /dev/null
+++ b/.github/workflows/release-windows.yml
@@ -0,0 +1,34 @@
+# Builds the Windows installer on a Windows runner (node-pty must be
+# compiled with MSVC, which cannot be cross-compiled from macOS) and
+# attaches it to the GitHub release for the pushed tag.
+name: Release (Windows)
+
+on:
+  push:
+    tags:
+      - 'v*'
+  workflow_dispatch:
+
+permissions:
+  contents: write
+
+jobs:
+  windows:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build
+        run: npm run build
+
+      - name: Package and publish Windows installer
+        run: npx electron-builder --win --publish always
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/README.md b/README.md
index 046433b..a648000 100644
--- a/README.md
+++ b/README.md
@@ -30,8 +30,9 @@ Download the latest `.dmg` from [Releases](https://github.com/YurenHao0426/latte
 
 ### Requirements
 
-- macOS (Apple Silicon)
-- [TeX Live](https://www.tug.org/texlive/) or [MacTeX](https://www.tug.org/mactex/) for local compilation
+- macOS (Apple Silicon) — primary platform
+- Windows 10+ (x64) — experimental installer built by CI (`lattex-*-win-x64.exe`); expects [TeX Live](https://www.tug.org/texlive/) or [MiKTeX](https://miktex.org/) for local compilation
+- [TeX Live](https://www.tug.org/texlive/) or [MacTeX](https://www.tug.org/mactex/) for local compilation on macOS
 
 ## Recommended: Claude Code
 
diff --git a/electron-builder.yml b/electron-builder.yml
index 6f74aa6..fba8e54 100644
--- a/electron-builder.yml
+++ b/electron-builder.yml
@@ -34,3 +34,13 @@ mac:
     - dmg
   category: public.app-category.productivity
   artifactName: ${name}-${version}-${arch}.${ext}
+win:
+  icon: resources/icon.png
+  target:
+    - nsis
+  artifactName: ${name}-${version}-win-${arch}.${ext}
+nsis:
+  oneClick: false
+  allowToChangeInstallationDirectory: true
+publish:
+  provider: github
diff --git a/resources/icon.png b/resources/icon.png
new file mode 100644
index 0000000..a3762f0
--- /dev/null
+++ b/resources/icon.png
diff --git a/src/main/compilationManager.ts b/src/main/compilationManager.ts
index 72c0c5e..2e27476 100644
--- a/src/main/compilationManager.ts
+++ b/src/main/compilationManager.ts
@@ -2,7 +2,7 @@
 // Licensed under AGPL-3.0 - see LICENSE file
 
 // Manages temp directory for Overleaf socket-mode compilation
-import { join, basename } from 'path'
+import { join, basename, dirname, delimiter } from 'path'
 import { writeFile, mkdir, rm } from 'fs/promises'
 import { existsSync } from 'fs'
 import { spawn } from 'child_process'
@@ -42,7 +42,7 @@ export class CompilationManager {
     await mkdir(this.tmpDir, { recursive: true })
     for (const [relPath, content] of this.docContents) {
       const fullPath = join(this.tmpDir, relPath)
-      const dir = fullPath.substring(0, fullPath.lastIndexOf('/'))
+      const dir = dirname(fullPath)
       await mkdir(dir, { recursive: true })
       await writeFile(fullPath, content, 'utf-8')
     }
@@ -53,7 +53,7 @@ export class CompilationManager {
     if (this.fileRefCache.has(relativePath)) return
 
     const fullPath = join(this.tmpDir, relativePath)
-    const dir = fullPath.substring(0, fullPath.lastIndexOf('/'))
+    const dir = dirname(fullPath)
     await mkdir(dir, { recursive: true })
 
     return new Promise((resolve, reject) => {
@@ -99,17 +99,23 @@ export class CompilationManager {
   ): Promise<{ success: boolean; log: string; pdfPath: string }> {
     await this.syncDocs()
 
-    const texPaths = [
-      '/Library/TeX/texbin',
-      '/usr/local/texlive/2024/bin/universal-darwin',
-      '/usr/texbin',
-      '/opt/homebrew/bin'
-    ]
-    const envPath = texPaths.join(':') + ':' + (process.env.PATH || '')
+    const texPaths = process.platform === 'win32'
+      ? [
+          'C:\\texlive\\2025\\bin\\windows',
+          'C:\\texlive\\2024\\bin\\windows',
+          join(process.env.LOCALAPPDATA || '', 'Programs', 'MiKTeX', 'miktex', 'bin', 'x64')
+        ]
+      : [
+          '/Library/TeX/texbin',
+          '/usr/local/texlive/2024/bin/universal-darwin',
+          '/usr/texbin',
+          '/opt/homebrew/bin'
+        ]
+    const envPath = texPaths.join(delimiter) + delimiter + (process.env.PATH || '')
 
     // Use // suffix for recursive search of ALL subdirectories in the project tree.
     // This ensures .sty, .bst, .cls, images, etc. are always found regardless of nesting.
-    const texInputs = `${this.tmpDir}//:`
+    const texInputs = `${this.tmpDir}//${delimiter}`
     const texBase = basename(mainTexRelPath, '.tex')
     const pdfPath = join(this.tmpDir, texBase + '.pdf')
 
diff --git a/src/main/fileSyncBridge.ts b/src/main/fileSyncBridge.ts
index 3072ae6..ae22eb8 100644
--- a/src/main/fileSyncBridge.ts
+++ b/src/main/fileSyncBridge.ts
@@ -2,7 +2,8 @@
 // Licensed under AGPL-3.0 - see LICENSE file
 
 // Bidirectional file sync bridge: temp dir ↔ Overleaf via OT (text) + REST (binary)
-import { join, dirname } from 'path'
+import { join, dirname, relative, sep } from 'path'
+import { tmpdir } from 'os'
 import { existsSync } from 'fs'
 import { readFile, writeFile, mkdir, unlink, rename as fsRename, appendFile, readdir, rm } from 'fs/promises'
 import { createHash } from 'crypto'
@@ -16,7 +17,7 @@ import type { OtOp } from './otTypes'
 import { isInsert, isDelete } from './otTypes'
 
 const dmp = new diff_match_patch()
-const LOG_FILE = '/tmp/lattex-bridge.log'
+const LOG_FILE = join(tmpdir(), 'lattex-bridge.log')
 function bridgeLog(msg: string, ...rest: unknown[]) {
   const line = `[${new Date().toISOString()}] ${msg}${rest.length ? ' ' + rest.map(String).join(' ') : ''}`
   console.log(line)
@@ -225,7 +226,7 @@ export class FileSyncBridge {
     }, 60_000)
 
     this.watcher.on('change', (absPath: string) => {
-      const relPath = absPath.replace(this.tmpDir + '/', '')
+      const relPath = this.relFromAbs(absPath)
       bridgeLog(`[FileSyncBridge] chokidar change: ${relPath}`)
       // A real fs event means new content — give parked failures a fresh chance
       this.permanentFailures.delete(relPath)
@@ -237,7 +238,7 @@ export class FileSyncBridge {
     })
 
     this.watcher.on('add', (absPath: string) => {
-      const relPath = absPath.replace(this.tmpDir + '/', '')
+      const relPath = this.relFromAbs(absPath)
       bridgeLog(`[FileSyncBridge] chokidar add: ${relPath}`)
       this.permanentFailures.delete(relPath)
       if (this.pathDocMap[relPath] || this.pathFileRefMap[relPath]) {
@@ -250,7 +251,7 @@ export class FileSyncBridge {
     })
 
     this.watcher.on('unlink', (absPath: string) => {
-      const relPath = absPath.replace(this.tmpDir + '/', '')
+      const relPath = this.relFromAbs(absPath)
       bridgeLog(`[FileSyncBridge] chokidar unlink: ${relPath}`)
     })
 
@@ -1478,6 +1479,12 @@ export class FileSyncBridge {
     }
   }
 
+  /** Absolute watcher path → project-relative path with forward slashes
+      (Windows watcher events use backslashes; all maps are '/'-keyed) */
+  private relFromAbs(absPath: string): string {
+    return relative(this.tmpDir, absPath).split(sep).join('/')
+  }
+
   // ── Compile-artifact detection ───────────────────────────────
 
   /** Register a file our own local compile will write (e.g. root main.pdf) */
diff --git a/src/main/index.ts b/src/main/index.ts
index 4f23762..8dffc26 100644
--- a/src/main/index.ts
+++ b/src/main/index.ts
@@ -2,7 +2,7 @@
 // Licensed under AGPL-3.0 - see LICENSE file
 
 import { app, BrowserWindow, ipcMain, dialog, shell, net } from 'electron'
-import { join, basename, dirname, relative, extname } from 'path'
+import { join, basename, dirname, relative, extname, delimiter } from 'path'
 import { copyFile, readFile, writeFile, mkdir as mkdirAsync, unlink, readdir, stat, rename as fsRename, rm, cp } from 'fs/promises'
 import { existsSync } from 'fs'
 import { spawn } from 'child_process'
@@ -125,8 +125,11 @@ function createWindow(): void {
     height: 900,
     minWidth: 900,
     minHeight: 600,
-    titleBarStyle: 'hiddenInset',
-    trafficLightPosition: { x: 15, y: 15 },
+    // Frameless inset title bar is a macOS affordance; use the native
+    // frame elsewhere
+    ...(process.platform === 'darwin'
+      ? { titleBarStyle: 'hiddenInset' as const, trafficLightPosition: { x: 15, y: 15 } }
+      : {}),
     webPreferences: {
       preload: join(__dirname, '../preload/index.js'),
       sandbox: false,
@@ -255,19 +258,25 @@ ipcMain.handle('settings:setApiKeys', async (_e, keys: Record<string, string>) =
 
 // ── LaTeX Compilation ────────────────────────────────────────────
 
-// Ensure TeX binaries are in PATH (Electron launched from Finder may miss them)
-const texPaths = ['/Library/TeX/texbin', '/usr/local/texlive/2024/bin/universal-darwin', '/usr/texbin', '/opt/homebrew/bin']
+// Ensure TeX binaries are in PATH (GUI-launched apps may miss them)
+const texPaths = process.platform === 'win32'
+  ? [
+      'C:\\texlive\\2025\\bin\\windows',
+      'C:\\texlive\\2024\\bin\\windows',
+      join(process.env.LOCALAPPDATA || '', 'Programs', 'MiKTeX', 'miktex', 'bin', 'x64')
+    ]
+  : ['/Library/TeX/texbin', '/usr/local/texlive/2024/bin/universal-darwin', '/usr/texbin', '/opt/homebrew/bin']
 const currentPath = process.env.PATH || ''
 for (const p of texPaths) {
   if (!currentPath.includes(p)) {
-    process.env.PATH = `${p}:${process.env.PATH}`
+    process.env.PATH = `${p}${delimiter}${process.env.PATH}`
   }
 }
 
 // SyncTeX: PDF position → source file:line (inverse search)
 ipcMain.handle('synctex:editFromPdf', async (_e, pdfPath: string, page: number, x: number, y: number) => {
   return new Promise<{ file: string; line: number } | null>((resolve) => {
-    const pdfDir = pdfPath.substring(0, pdfPath.lastIndexOf('/'))
+    const pdfDir = dirname(pdfPath)
     console.log(`[synctex] edit -o ${page}:${x}:${y}:${pdfPath} (cwd: ${pdfDir})`)
     const proc = spawn('synctex', ['edit', '-o', `${page}:${x}:${y}:${pdfPath}`], {
       env: process.env,
@@ -418,8 +427,10 @@ ipcMain.handle('pty:spawn', async (_e, id: string, cwd: string, cmd?: string, ar
     ptyInstances.delete(id)
   }
 
-  const shellPath = cmd || process.env.SHELL || '/bin/zsh'
-  const shellArgs = args || ['-l']
+  const shellPath = cmd || (process.platform === 'win32'
+    ? process.env.COMSPEC || 'powershell.exe'
+    : process.env.SHELL || '/bin/zsh')
+  const shellArgs = args || (process.platform === 'win32' ? [] : ['-l'])
   const ptyEnv: Record<string, string> = {
     ...(process.env as Record<string, string>),
     TERM: 'xterm-256color',