diff --git a/scripts/setup-windows-dev.ps1 b/scripts/setup-windows-dev.ps1
new file mode 100644
index 0000000..f17a678
--- /dev/null
+++ b/scripts/setup-windows-dev.ps1
@@ -0,0 +1,121 @@
+#Requires -Version 5.1
+<#
+.SYNOPSIS
+  Non-elevated WABOX development setup for Windows 11 24H2+.
+
+.DESCRIPTION
+  Installs npm deps, creates .env from template, builds TypeScript, and runs
+  preflight checks. For MXC host prep (one-time, elevated), run:
+    .\scripts\setup-mxc-host.ps1
+
+.USAGE
+  # PowerShell from repo root:
+  .\scripts\setup-windows-dev.ps1
+  .\scripts\setup-windows-dev.ps1 -SkipWarmup
+  .\scripts\setup-windows-dev.ps1 -RunIntegration
+#>
+param(
+  [switch] $SkipWarmup,
+  [switch] $RunIntegration,
+  [switch] $RunExample
+)
+
+$ErrorActionPreference = 'Stop'
+$RepoRoot = Split-Path -Parent $PSScriptRoot
+Set-Location $RepoRoot
+
+function Write-Step([string]$Message) {
+  Write-Host "`n=== $Message ===" -ForegroundColor Cyan
+}
+
+function Assert-Command([string]$Name) {
+  if (-not (Get-Command $Name -ErrorAction SilentlyContinue)) {
+    throw "$Name is not on PATH. Install it and retry."
+  }
+}
+
+Write-Step 'Checking prerequisites'
+Assert-Command node
+Assert-Command npm
+
+$nodeMajor = [int]((node -p "process.versions.node.split('.')[0]"))
+if ($nodeMajor -lt 18) {
+  throw "Node.js >= 18 required; found $(node -v)"
+}
+
+if ($env:OS -ne 'Windows_NT') {
+  throw 'WABOX requires Windows. Use Cursor My Machines or a Windows devbox.'
+}
+
+$build = [System.Environment]::OSVersion.Version
+if ($build.Major -lt 10 -or ($build.Major -eq 10 -and $build.Build -lt 26100)) {
+  Write-Warning "Windows 11 24H2+ (build 26100+) is recommended. Current build: $($build.Build)"
+}
+
+Write-Step 'Installing npm dependencies'
+npm install
+if ($LASTEXITCODE -ne 0) { throw 'npm install failed' }
+
+Write-Step 'Creating .env from template'
+$envFile = Join-Path $RepoRoot '.env'
+$envExample = Join-Path $RepoRoot '.env.example'
+if (-not (Test-Path $envFile)) {
+  Copy-Item $envExample $envFile
+}
+$workspace = ($RepoRoot -replace '\\', '/')
+$content = Get-Content $envFile -Raw
+$content = $content -replace 'WABOX_WORKSPACE_PATH=.*', "WABOX_WORKSPACE_PATH=$workspace"
+if ($content -notmatch 'WABOX_WORKSPACE_PATH=') {
+  $content += "`nWABOX_WORKSPACE_PATH=$workspace`n"
+}
+Set-Content -Path $envFile -Value $content.TrimEnd() -NoNewline
+Write-Host "WABOX_WORKSPACE_PATH=$workspace"
+
+Write-Step 'Building TypeScript'
+npm run build
+if ($LASTEXITCODE -ne 0) { throw 'npm run build failed' }
+
+Write-Step 'Running unit tests'
+npm test
+if ($LASTEXITCODE -ne 0) { throw 'npm test failed' }
+
+$hostPrep = Join-Path $RepoRoot 'node_modules\@microsoft\mxc-sdk\bin\x64\wxc-host-prep.exe'
+if (Test-Path $hostPrep) {
+  Write-Step 'MXC host prep reminder'
+  Write-Host 'If diagnose/warmup hang or fail, run elevated once:'
+  Write-Host '  .\scripts\setup-mxc-host.ps1' -ForegroundColor Yellow
+} else {
+  Write-Warning 'wxc-host-prep not found after npm install'
+}
+
+if (-not $SkipWarmup) {
+  Write-Step 'Warming up MXC (first spawn can be slow)'
+  npm run warmup
+  if ($LASTEXITCODE -ne 0) {
+    Write-Warning 'warmup failed — try elevated setup-mxc-host.ps1 then npm run warmup'
+  }
+}
+
+Write-Step 'Running diagnose preflight'
+npm run diagnose
+if ($LASTEXITCODE -ne 0) {
+  Write-Warning 'diagnose reported issues — see .wabox/diagnostics/latest.json'
+}
+
+if ($RunExample) {
+  Write-Step 'Running minimal example'
+  npm run example
+  if ($LASTEXITCODE -ne 0) { throw 'npm run example failed' }
+}
+
+if ($RunIntegration) {
+  Write-Step 'Running integration tests'
+  $env:WABOX_INTEGRATION = '1'
+  npm run test:integration
+  if ($LASTEXITCODE -ne 0) { throw 'npm run test:integration failed' }
+}
+
+Write-Host "`nDone. Next steps:" -ForegroundColor Green
+Write-Host '  npm run example          # smoke test sandbox exec'
+Write-Host '  npm run diagnose         # full MXC preflight'
+Write-Host '  npm run test:integration # set WABOX_INTEGRATION=1 on Windows'