diff --git a/docs/开发与部署SOP.md b/docs/开发与部署SOP.md
index dc7430b9..bf91abd3 100644
--- a/docs/开发与部署SOP.md
+++ b/docs/开发与部署SOP.md
@@ -33,6 +33,7 @@
 项目使用专属构建器 `caiwu-builder`，缓存与其他项目分开：
 
 - 前端在 Windows 主机使用项目专用 Node 20 构建，避开 Docker 虚拟机内存上限；
+- 前端输入指纹未变化时直接复用上次产物，纯后端改动不重复打包前端；
 - PHP 扩展层只在 Dockerfile 的基础环境变化时重建；
 - Composer 只在 `composer.lock` 变化时重新解析依赖，并复用下载缓存；
 - npm 优先使用本机下载缓存，`node_modules` 原位刷新，不会逐版本堆积；
diff --git a/scripts/build-frontend.ps1 b/scripts/build-frontend.ps1
index fa1112c5..6f7edd6e 100644
--- a/scripts/build-frontend.ps1
+++ b/scripts/build-frontend.ps1
@@ -16,6 +16,7 @@ $archivePath = Join-Path $toolRoot $archiveName
 $checksumPath = Join-Path $toolRoot 'SHASUMS256.txt'
 $trackedCssPath = Join-Path $repoRoot 'public/css/app.css'
 $frontendOutputRoot = Join-Path $repoRoot '.caiwu-build/public'
+$fingerprintPath = Join-Path $repoRoot '.caiwu-build/frontend.sha'
 
 function Invoke-Native {
     param(
@@ -31,6 +32,30 @@ function Invoke-Native {
     }
 }
 
+$fingerprintInputs = @(
+    'HEAD:resources',
+    'HEAD:package.json',
+    'HEAD:package-lock.json',
+    'HEAD:webpack.mix.js',
+    'HEAD:tailwind.config.js'
+)
+$fingerprintHashes = @(& git -C $repoRoot rev-parse @fingerprintInputs)
+if ($LASTEXITCODE -ne 0) {
+    throw '无法计算前端输入指纹。'
+}
+$frontendFingerprint = "$NodeVersion|$($fingerprintHashes -join '|')"
+$cachedOutputs = @(
+    (Join-Path $frontendOutputRoot 'js/auth/common.min.js'),
+    (Join-Path $frontendOutputRoot 'css/app.css'),
+    (Join-Path $frontendOutputRoot 'mix-manifest.json'),
+    $fingerprintPath
+)
+$cacheComplete = -not ($cachedOutputs | Where-Object { -not (Test-Path -LiteralPath $_) })
+if ($cacheComplete -and (Get-Content -Raw -LiteralPath $fingerprintPath).Trim() -eq $frontendFingerprint) {
+    Write-Host '前端输入未变化，复用已有构建产物。'
+    return
+}
+
 if (-not (Test-Path -LiteralPath $nodeExe)) {
     New-Item -ItemType Directory -Force -Path $toolRoot | Out-Null
 
@@ -105,6 +130,7 @@ try {
     Copy-Item -LiteralPath (Join-Path $repoRoot 'public/js') -Destination $frontendOutputRoot -Recurse
     Copy-Item -LiteralPath (Join-Path $repoRoot 'public/css/app.css') -Destination (Join-Path $frontendOutputRoot 'css/app.css')
     Copy-Item -LiteralPath (Join-Path $repoRoot 'public/mix-manifest.json') -Destination $frontendOutputRoot
+    Set-Content -LiteralPath $fingerprintPath -Value $frontendFingerprint -NoNewline
 }
 finally {
     Pop-Location
diff --git a/scripts/deploy-from-workstation.ps1 b/scripts/deploy-from-workstation.ps1
index 07fb2346..d0d70134 100644
--- a/scripts/deploy-from-workstation.ps1
+++ b/scripts/deploy-from-workstation.ps1
@@ -145,8 +145,8 @@ try {
             .
     } '本机镜像构建失败。服务器未发生任何变更。'
 
-    $previousShaOutput = & ssh -i $keyFullPath -o BatchMode=yes -o StrictHostKeyChecking=accept-new $sshTarget "cat '$RemotePath/.deployed-sha' 2>/dev/null || true"
-    $previousSha = ([string]$previousShaOutput).Trim()
+    $previousShaOutput = @(& ssh -i $keyFullPath -o BatchMode=yes -o StrictHostKeyChecking=accept-new $sshTarget "cat '$RemotePath/.deployed-sha' 2>/dev/null || true")
+    $previousSha = ($previousShaOutput -join "`n").Trim()
     if ($LASTEXITCODE -ne 0) {
         throw '无法连接服务器。'
     }