diff --git a/install_python_stack.py b/install_python_stack.py
new file mode 100644
index 0000000000..c9b73034b4
--- /dev/null
+++ b/install_python_stack.py
@@ -0,0 +1,245 @@
+#!/usr/bin/env python3
+"""Cross-platform Python dependency installer for Unsloth Studio.
+
+Called by both setup.sh (Linux / WSL) and setup.ps1 (Windows) after the
+virtual environment is already activated.  Expects `pip` and `python` on
+PATH to point at the venv.
+"""
+
+from __future__ import annotations
+
+import os
+import subprocess
+import sys
+import tempfile
+import urllib.request
+from pathlib import Path
+
+IS_WINDOWS = sys.platform == "win32"
+
+# ── Paths ──────────────────────────────────────────────────────────────
+SCRIPT_DIR = Path(__file__).resolve().parent
+REQ_ROOT = SCRIPT_DIR / "studio" / "backend" / "requirements"
+SINGLE_ENV = REQ_ROOT / "single-env"
+CONSTRAINTS = SINGLE_ENV / "constraints.txt"
+
+# ── Color support ──────────────────────────────────────────────────────
+
+def _enable_colors() -> bool:
+    """Try to enable ANSI color support. Returns True if available."""
+    if not hasattr(sys.stdout, "fileno"):
+        return False
+    try:
+        if not os.isatty(sys.stdout.fileno()):
+            return False
+    except Exception:
+        return False
+    if IS_WINDOWS:
+        try:
+            import ctypes
+            kernel32 = ctypes.windll.kernel32
+            # Enable ENABLE_VIRTUAL_TERMINAL_PROCESSING (0x0004) on stdout
+            handle = kernel32.GetStdHandle(-11)  # STD_OUTPUT_HANDLE
+            mode = ctypes.c_ulong()
+            kernel32.GetConsoleMode(handle, ctypes.byref(mode))
+            kernel32.SetConsoleMode(handle, mode.value | 0x0004)
+            return True
+        except Exception:
+            return False
+    return True  # Unix terminals support ANSI by default
+
+_HAS_COLOR = _enable_colors()
+
+def _green(msg: str) -> str:
+    return f"\033[92m{msg}\033[0m" if _HAS_COLOR else msg
+
+def _cyan(msg: str) -> str:
+    return f"\033[96m{msg}\033[0m" if _HAS_COLOR else msg
+
+def _red(msg: str) -> str:
+    return f"\033[91m{msg}\033[0m" if _HAS_COLOR else msg
+
+
+def run(label: str, cmd: list[str], *, quiet: bool = True) -> None:
+    """Run a command; on failure print output and exit."""
+    print(_cyan(f"   {label}..."))
+    result = subprocess.run(
+        cmd,
+        stdout=subprocess.PIPE if quiet else None,
+        stderr=subprocess.STDOUT if quiet else None,
+    )
+    if result.returncode != 0:
+        print(_red(f"❌ {label} failed (exit code {result.returncode}):"))
+        if result.stdout:
+            print(result.stdout.decode(errors="replace"))
+        sys.exit(result.returncode)
+
+
+# Packages to skip on Windows (require special build steps)
+WINDOWS_SKIP_PACKAGES = {"open_spiel"}
+
+
+def _filter_requirements(req: Path, skip: set[str]) -> Path:
+    """Return a temp copy of a requirements file with certain packages removed."""
+    lines = req.read_text(encoding="utf-8").splitlines(keepends=True)
+    filtered = [
+        line for line in lines
+        if not any(line.strip().lower().startswith(pkg) for pkg in skip)
+    ]
+    tmp = tempfile.NamedTemporaryFile(
+        mode="w", suffix=".txt", delete=False, encoding="utf-8",
+    )
+    tmp.writelines(filtered)
+    tmp.close()
+    return Path(tmp.name)
+
+
+def pip_install(
+    label: str,
+    *args: str,
+    req: Path | None = None,
+    constrain: bool = True,
+) -> None:
+    """Build and run a pip install command."""
+    cmd = [sys.executable, "-m", "pip", "install"]
+    cmd.extend(args)
+    if constrain and CONSTRAINTS.is_file():
+        cmd.extend(["-c", str(CONSTRAINTS)])
+    actual_req = req
+    if req is not None and IS_WINDOWS and WINDOWS_SKIP_PACKAGES:
+        actual_req = _filter_requirements(req, WINDOWS_SKIP_PACKAGES)
+    if actual_req is not None:
+        cmd.extend(["-r", str(actual_req)])
+    try:
+        run(label, cmd)
+    finally:
+        # Clean up temp file if we created one
+        if actual_req is not None and actual_req != req:
+            actual_req.unlink(missing_ok=True)
+
+
+
+def download_file(url: str, dest: Path) -> None:
+    """Download a file using urllib (no curl dependency)."""
+    urllib.request.urlretrieve(url, dest)
+
+
+def patch_package_file(package_name: str, relative_path: str, url: str) -> None:
+    """Download a file from url and overwrite a file inside an installed package."""
+    result = subprocess.run(
+        [sys.executable, "-m", "pip", "show", package_name],
+        capture_output=True, text=True,
+    )
+    if result.returncode != 0:
+        print(_red(f"   ⚠️  Could not find package {package_name}, skipping patch"))
+        return
+
+    location = None
+    for line in result.stdout.splitlines():
+        if line.lower().startswith("location:"):
+            location = line.split(":", 1)[1].strip()
+            break
+
+    if not location:
+        print(_red(f"   ⚠️  Could not determine location of {package_name}"))
+        return
+
+    dest = Path(location) / relative_path
+    print(_cyan(f"   Patching {dest.name} in {package_name}..."))
+    download_file(url, dest)
+
+
+# ── Main install sequence ─────────────────────────────────────────────
+
+def install_python_stack() -> int:
+    print(_cyan("── Installing Python stack ──"))
+
+    # 1. Upgrade pip
+    run("Upgrading pip", [sys.executable, "-m", "pip", "install", "--upgrade", "pip"])
+
+    # 2. Core packages: unsloth-zoo + unsloth
+    pip_install(
+        "Installing unsloth-zoo + unsloth",
+        "--no-cache-dir",
+        req=REQ_ROOT / "base.txt",
+    )
+
+    # 3. Extra dependencies
+    pip_install(
+        "Installing additional unsloth dependencies",
+        "--no-cache-dir",
+        req=REQ_ROOT / "extras.txt",
+    )
+
+    # 4. Overrides (torchao, transformers) — force-reinstall
+    pip_install(
+        "Installing torchao + transformers overrides",
+        "--force-reinstall", "--no-cache-dir",
+        req=REQ_ROOT / "overrides.txt",
+    )
+
+    # 5. Triton kernels (no-deps, from source)
+    pip_install(
+        "Installing triton kernels",
+        "--no-deps", "--no-cache-dir",
+        req=REQ_ROOT / "triton-kernels.txt",
+        constrain=False,
+    )
+
+    # 6. Patch: override llama_cpp.py with fix from unsloth-zoo  feature/llama-cpp-windows-support branch
+    patch_package_file(
+        "unsloth-zoo",
+        os.path.join("unsloth_zoo", "llama_cpp.py"),
+        "https://raw.githubusercontent.com/unslothai/unsloth-zoo/refs/heads/main/unsloth_zoo/llama_cpp.py",
+    )
+
+    # 7a. Patch: override vision.py with fix from unsloth PR #4091
+    patch_package_file(
+        "unsloth",
+        os.path.join("unsloth", "models", "vision.py"),
+        "https://raw.githubusercontent.com/unslothai/unsloth/80e0108a684c882965a02a8ed851e3473c1145ab/unsloth/models/vision.py",
+    )
+
+    # 7b. Patch : override save.py with fix from feature/llama-cpp-windows-support
+    patch_package_file(
+        "unsloth",
+        os.path.join("unsloth", "save.py"),
+        "https://raw.githubusercontent.com/unslothai/unsloth/refs/heads/main/unsloth/save.py",
+    )
+
+    # 8. Studio dependencies
+    pip_install(
+        "Installing studio dependencies",
+        "--no-cache-dir",
+        req=REQ_ROOT / "studio.txt",
+    )
+
+    # 9. Data-designer dependencies
+    pip_install(
+        "Installing data-designer dependencies",
+        "--no-cache-dir",
+        req=SINGLE_ENV / "data-designer-deps.txt",
+    )
+
+    # 10. Data-designer packages (no-deps to avoid conflicts)
+    pip_install(
+        "Installing data-designer",
+        "--no-cache-dir", "--no-deps",
+        req=SINGLE_ENV / "data-designer.txt",
+    )
+
+    # 11. Patch metadata for single-env compatibility
+    run(
+        "Patching single-env metadata",
+        [sys.executable, str(SINGLE_ENV / "patch_metadata.py")],
+    )
+
+    # 12. Final check
+    run("Running pip check", [sys.executable, "-m", "pip", "check"], quiet=False)
+
+    print(_green("✅ Python dependencies installed"))
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(install_python_stack())
diff --git a/setup.bat b/setup.bat
new file mode 100644
index 0000000000..ef16abd263
--- /dev/null
+++ b/setup.bat
@@ -0,0 +1,2 @@
+@echo off
+powershell -ExecutionPolicy Bypass -File "%~dp0setup.ps1" %*
diff --git a/setup.ps1 b/setup.ps1
new file mode 100644
index 0000000000..8a2ec56033
--- /dev/null
+++ b/setup.ps1
@@ -0,0 +1,964 @@
+#Requires -Version 5.1
+<#
+.SYNOPSIS
+    Full environment setup for Unsloth Studio on Windows (bundled version).
+.DESCRIPTION
+    Always installs Node.js if needed. When running from pip install:
+    skips frontend build (already bundled). When running from git repo:
+    full setup including frontend build.
+    Requires an NVIDIA GPU -- CPU-only machines are not supported.
+.NOTES
+    Usage: powershell -ExecutionPolicy Bypass -File setup.ps1
+#>
+
+$ErrorActionPreference = "Stop"
+$ScriptDir = Split-Path -Parent $MyInvocation.MyCommand.Path
+$PackageDir = Split-Path -Parent $ScriptDir
+
+# Detect if running from pip install (no studio/frontend/ dir in repo)
+$FrontendDir = Join-Path $ScriptDir "studio\frontend"
+$IsPipInstall = -not (Test-Path $FrontendDir)
+
+# ─────────────────────────────────────────────
+# Helper functions
+# ─────────────────────────────────────────────
+
+# Reload ALL environment variables from registry.
+# Picks up changes made by installers (winget, msi, etc.) including
+# Path, CUDA_PATH, CUDA_PATH_V*, and any other vars they set.
+function Refresh-Environment {
+    foreach ($level in @('Machine', 'User')) {
+        $vars = [System.Environment]::GetEnvironmentVariables($level)
+        foreach ($key in $vars.Keys) {
+            if ($key -eq 'Path') { continue }
+            Set-Item -Path "Env:$key" -Value $vars[$key] -ErrorAction SilentlyContinue
+        }
+    }
+    $machinePath = [System.Environment]::GetEnvironmentVariable('Path', 'Machine')
+    $userPath = [System.Environment]::GetEnvironmentVariable('Path', 'User')
+    $env:Path = "$machinePath;$userPath"
+}
+
+# Find nvcc on PATH, CUDA_PATH, or standard toolkit dirs.
+# Returns the path to nvcc.exe, or $null if not found.
+function Find-Nvcc {
+    param([string]$MaxVersion = "")
+
+    # If MaxVersion is set, we need to find a toolkit <= that version.
+    # CUDA toolkits install side-by-side under C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\vX.Y\
+
+    $toolkitBase = 'C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA'
+
+    if ($MaxVersion -and (Test-Path $toolkitBase)) {
+        $drMajor = [int]$MaxVersion.Split('.')[0]
+        $drMinor = [int]$MaxVersion.Split('.')[1]
+
+        # Get all installed CUDA dirs, sorted descending (highest first)
+        $cudaDirs = Get-ChildItem -Directory $toolkitBase | Where-Object {
+            $_.Name -match '^v(\d+)\.(\d+)'
+        } | Sort-Object { [version]($_.Name -replace '^v','') } -Descending
+
+        foreach ($dir in $cudaDirs) {
+            if ($dir.Name -match '^v(\d+)\.(\d+)') {
+                $tkMajor = [int]$Matches[1]; $tkMinor = [int]$Matches[2]
+                $compatible = ($tkMajor -lt $drMajor) -or ($tkMajor -eq $drMajor -and $tkMinor -le $drMinor)
+                if ($compatible) {
+                    $nvcc = Join-Path $dir.FullName 'bin\nvcc.exe'
+                    if (Test-Path $nvcc) {
+                        return $nvcc
+                    }
+                }
+            }
+        }
+
+        # No compatible side-by-side version found
+        return $null
+    }
+
+    # Fallback: no version constraint — pick latest or whatever is available
+
+    # 1. Check nvcc on PATH
+    $cmd = Get-Command nvcc -ErrorAction SilentlyContinue
+    if ($cmd) { return $cmd.Source }
+
+    # 2. Check CUDA_PATH env var
+    $cudaRoot = [Environment]::GetEnvironmentVariable('CUDA_PATH', 'Process')
+    if (-not $cudaRoot) { $cudaRoot = [Environment]::GetEnvironmentVariable('CUDA_PATH', 'Machine') }
+    if (-not $cudaRoot) { $cudaRoot = [Environment]::GetEnvironmentVariable('CUDA_PATH', 'User') }
+    if ($cudaRoot -and (Test-Path (Join-Path $cudaRoot 'bin\nvcc.exe'))) {
+        return (Join-Path $cudaRoot 'bin\nvcc.exe')
+    }
+
+    # 3. Scan standard toolkit directory
+    if (Test-Path $toolkitBase) {
+        $latest = Get-ChildItem -Directory $toolkitBase | Sort-Object Name | Select-Object -Last 1
+        if ($latest -and (Test-Path (Join-Path $latest.FullName 'bin\nvcc.exe'))) {
+            return (Join-Path $latest.FullName 'bin\nvcc.exe')
+        }
+    }
+
+    return $null
+}
+
+# Detect CUDA Compute Capability via nvidia-smi.
+# Returns e.g. "80" for A100 (8.0), "89" for RTX 4090 (8.9), etc.
+# Returns $null if detection fails.
+function Get-CudaComputeCapability {
+    $nvSmi = Get-Command nvidia-smi -ErrorAction SilentlyContinue
+    if (-not $nvSmi) { return $null }
+
+    try {
+        $raw = & nvidia-smi --query-gpu=compute_cap --format=csv,noheader 2>$null
+        if ($LASTEXITCODE -ne 0 -or -not $raw) { return $null }
+
+        # nvidia-smi may return multiple GPUs; take the first one
+        $cap = ($raw -split "`n")[0].Trim()
+        if ($cap -match '^(\d+)\.(\d+)$') {
+            $major = $Matches[1]
+            $minor = $Matches[2]
+            return "$major$minor"
+        }
+    } catch { }
+
+    return $null
+}
+
+# Detect driver's max CUDA version from nvidia-smi and return the highest
+# compatible PyTorch CUDA index tag (e.g. "cu128").
+# PyTorch on Windows ships CPU-only by default from PyPI; CUDA wheels live at
+# https://download.pytorch.org/whl/<tag>. The tag must not exceed the driver's
+# capability: e.g. driver "CUDA Version: 12.9" → cu128 (not cu130).
+function Get-PytorchCudaTag {
+    $nvSmi = Get-Command nvidia-smi -ErrorAction SilentlyContinue
+    if (-not $nvSmi) { return "cu124" }
+
+    try {
+        # 2>&1 | Out-String merges stderr into stdout then converts to a single
+        # string.  Plain 2>$null doesn't fully suppress stderr in PS 5.1 —
+        # ErrorRecord objects leak into $output and break the -match.
+        $output = & nvidia-smi 2>&1 | Out-String
+        if ($output -match 'CUDA Version:\s+(\d+)\.(\d+)') {
+            $major = [int]$Matches[1]
+            $minor = [int]$Matches[2]
+            # PyTorch 2.10 offers: cu124, cu126, cu128, cu130
+            if ($major -ge 13) { return "cu130" }
+            if ($major -eq 12 -and $minor -ge 8) { return "cu128" }
+            if ($major -eq 12 -and $minor -ge 6) { return "cu126" }
+            return "cu124"
+        }
+    } catch { }
+
+    return "cu124"
+}
+
+# Find Visual Studio Build Tools for cmake -G flag.
+# Strategy: (1) vswhere, (2) scan filesystem (handles broken vswhere registration).
+# Returns @{ Generator = "Visual Studio 17 2022"; InstallPath = "C:\..."; Source = "..." } or $null.
+function Find-VsBuildTools {
+    $map = @{ '2022' = '17'; '2019' = '16'; '2017' = '15' }
+
+    # --- Try vswhere first (works when VS is properly registered) ---
+    $vsw = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe"
+    if (Test-Path $vsw) {
+        $info = & $vsw -latest -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property catalog_productLineVersion 2>$null
+        $path = & $vsw -latest -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath 2>$null
+        if ($info -and $path) {
+            $y = $info.Trim()
+            $n = $map[$y]
+            if ($n) {
+                return @{ Generator = "Visual Studio $n $y"; InstallPath = $path.Trim(); Source = 'vswhere' }
+            }
+        }
+    }
+
+    # --- Scan filesystem (handles broken vswhere registration after winget cycles) ---
+    $roots = @($env:ProgramFiles, ${env:ProgramFiles(x86)})
+    $editions = @('BuildTools', 'Community', 'Professional', 'Enterprise')
+    $years = @('2022', '2019', '2017')
+
+    foreach ($y in $years) {
+        foreach ($r in $roots) {
+            foreach ($ed in $editions) {
+                $candidate = Join-Path $r "Microsoft Visual Studio\$y\$ed"
+                if (Test-Path $candidate) {
+                    $vcDir = Join-Path $candidate "VC\Tools\MSVC"
+                    if (Test-Path $vcDir) {
+                        $cl = Get-ChildItem -Path $vcDir -Filter "cl.exe" -Recurse -ErrorAction SilentlyContinue | Select-Object -First 1
+                        if ($cl) {
+                            $n = $map[$y]
+                            if ($n) {
+                                return @{ Generator = "Visual Studio $n $y"; InstallPath = $candidate; Source = "filesystem ($ed)"; ClExe = $cl.FullName }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    return $null
+}
+
+# ─────────────────────────────────────────────
+# Banner
+# ─────────────────────────────────────────────
+Write-Host "+==============================================+" -ForegroundColor Green
+Write-Host "|       Unsloth Studio Setup (Windows)         |" -ForegroundColor Green
+Write-Host "+==============================================+" -ForegroundColor Green
+
+# ==========================================================================
+#  PHASE 1: System-level prerequisites (winget installs, env vars)
+#  All heavy system tool installs happen here BEFORE touching Python.
+# ==========================================================================
+
+# ============================================
+# 1a. GPU requirement check
+# ============================================
+$HasNvidiaSmi = $null -ne (Get-Command nvidia-smi -ErrorAction SilentlyContinue)
+if (-not $HasNvidiaSmi) {
+    Write-Host ""
+    Write-Host "[ERROR] Unsloth Studio requires an NVIDIA GPU." -ForegroundColor Red
+    Write-Host "        CPU-only machines are not supported." -ForegroundColor Red
+    Write-Host ""
+    Write-Host "        If you have an NVIDIA GPU, ensure the driver is installed:" -ForegroundColor Yellow
+    Write-Host "        https://www.nvidia.com/Download/index.aspx" -ForegroundColor Yellow
+    exit 1
+}
+Write-Host "[OK] NVIDIA GPU detected" -ForegroundColor Green
+
+# ============================================
+# 1a.5. Windows Long Paths (required for deep node_modules / Python paths)
+# ============================================
+$LongPathsEnabled = $false
+try {
+    $regVal = Get-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Control\FileSystem" -Name "LongPathsEnabled" -ErrorAction SilentlyContinue
+    if ($regVal -and $regVal.LongPathsEnabled -eq 1) {
+        $LongPathsEnabled = $true
+    }
+} catch {}
+
+if ($LongPathsEnabled) {
+    Write-Host "[OK] Windows Long Paths enabled" -ForegroundColor Green
+} else {
+    Write-Host "Windows Long Paths not enabled (required for Triton compilation and deep dependency paths)." -ForegroundColor Yellow
+    Write-Host "   Requesting admin access to fix..." -ForegroundColor Yellow
+    try {
+        # Spawn an elevated process to set the registry key (triggers UAC prompt)
+        $proc = Start-Process -FilePath "reg.exe" `
+            -ArgumentList 'add "HKLM\SYSTEM\CurrentControlSet\Control\FileSystem" /v LongPathsEnabled /t REG_DWORD /d 1 /f' `
+            -Verb RunAs -Wait -PassThru -ErrorAction Stop
+        if ($proc.ExitCode -eq 0) {
+            $LongPathsEnabled = $true
+            Write-Host "[OK] Windows Long Paths enabled (via UAC)" -ForegroundColor Green
+        } else {
+            Write-Host "[WARN] Failed to enable Long Paths (exit code: $($proc.ExitCode))" -ForegroundColor Yellow
+        }
+    } catch {
+        Write-Host "[WARN] Could not enable Long Paths (UAC was declined or not available)" -ForegroundColor Yellow
+        Write-Host "       Run this manually in an Admin terminal:" -ForegroundColor Yellow
+        Write-Host '       reg add "HKLM\SYSTEM\CurrentControlSet\Control\FileSystem" /v LongPathsEnabled /t REG_DWORD /d 1 /f' -ForegroundColor Cyan
+    }
+}
+
+# ============================================
+# 1b. Git (required by pip for git+https:// deps and by npm)
+# ============================================
+$HasGit = $null -ne (Get-Command git -ErrorAction SilentlyContinue)
+if (-not $HasGit) {
+    Write-Host "Git not found -- installing via winget..." -ForegroundColor Yellow
+    $HasWinget = $null -ne (Get-Command winget -ErrorAction SilentlyContinue)
+    if ($HasWinget) {
+        try {
+            winget install Git.Git --source winget --accept-package-agreements --accept-source-agreements 2>&1 | Out-Null
+            Refresh-Environment
+            $HasGit = $null -ne (Get-Command git -ErrorAction SilentlyContinue)
+        } catch { }
+    }
+    if (-not $HasGit) {
+        Write-Host "[ERROR] Git is required but could not be installed automatically." -ForegroundColor Red
+        Write-Host "        Install Git from https://git-scm.com/download/win and re-run." -ForegroundColor Red
+        exit 1
+    }
+    Write-Host "[OK] Git installed: $(git --version)" -ForegroundColor Green
+} else {
+    Write-Host "[OK] Git found: $(git --version)" -ForegroundColor Green
+}
+
+# ============================================
+# 1c. CMake (required for llama.cpp build)
+# ============================================
+$HasCmake = $null -ne (Get-Command cmake -ErrorAction SilentlyContinue)
+if (-not $HasCmake) {
+    Write-Host "CMake not found -- installing via winget..." -ForegroundColor Yellow
+    $HasWinget = $null -ne (Get-Command winget -ErrorAction SilentlyContinue)
+    if ($HasWinget) {
+        try {
+            winget install Kitware.CMake --source winget --accept-package-agreements --accept-source-agreements 2>&1 | Out-Null
+            Refresh-Environment
+            $HasCmake = $null -ne (Get-Command cmake -ErrorAction SilentlyContinue)
+        } catch { }
+    }
+    if ($HasCmake) {
+        Write-Host "[OK] CMake installed" -ForegroundColor Green
+    } else {
+        Write-Host "[ERROR] CMake is required but could not be installed." -ForegroundColor Red
+        Write-Host "        Install CMake from https://cmake.org/download/ and re-run." -ForegroundColor Red
+        exit 1
+    }
+} else {
+    Write-Host "[OK] CMake found: $(cmake --version | Select-Object -First 1)" -ForegroundColor Green
+}
+
+# ============================================
+# 1d. Visual Studio Build Tools (C++ compiler for llama.cpp)
+# ============================================
+$CmakeGenerator = $null
+$VsInstallPath = $null
+$vsResult = Find-VsBuildTools
+
+if (-not $vsResult) {
+    Write-Host "Visual Studio Build Tools not found -- installing via winget..." -ForegroundColor Yellow
+    Write-Host "   (This is a one-time install, may take several minutes)" -ForegroundColor Gray
+    $HasWinget = $null -ne (Get-Command winget -ErrorAction SilentlyContinue)
+    if ($HasWinget) {
+        $prevEAPTemp = $ErrorActionPreference
+        $ErrorActionPreference = "Continue"
+        winget install Microsoft.VisualStudio.2022.BuildTools --source winget --accept-package-agreements --accept-source-agreements --override "--add Microsoft.VisualStudio.Workload.VCTools --includeRecommended --passive --wait"
+        $ErrorActionPreference = $prevEAPTemp
+        # Re-scan after install (don't trust vswhere catalog)
+        $vsResult = Find-VsBuildTools
+    }
+}
+
+if ($vsResult) {
+    $CmakeGenerator = $vsResult.Generator
+    $VsInstallPath = $vsResult.InstallPath
+    Write-Host "[OK] $CmakeGenerator detected via $($vsResult.Source)" -ForegroundColor Green
+    if ($vsResult.ClExe) { Write-Host "   cl.exe: $($vsResult.ClExe)" -ForegroundColor Gray }
+} else {
+    Write-Host "[ERROR] Visual Studio Build Tools could not be found or installed." -ForegroundColor Red
+    Write-Host "        Manual install:" -ForegroundColor Red
+    Write-Host '        1. winget install Microsoft.VisualStudio.2022.BuildTools --source winget' -ForegroundColor Yellow
+    Write-Host '        2. Open Visual Studio Installer -> Modify -> check "Desktop development with C++"' -ForegroundColor Yellow
+    exit 1
+}
+
+# ============================================
+# 1e. CUDA Toolkit (nvcc for llama.cpp build + env vars)
+# ============================================
+# IMPORTANT: The CUDA Toolkit version must be <= the max CUDA version the
+# NVIDIA driver supports.  nvidia-smi reports this as "CUDA Version: X.Y".
+# If we install a toolkit newer than the driver supports, llama-server will
+# fail at runtime with "ggml_cuda_init: failed to initialize CUDA: (null)".
+
+# -- Detect max CUDA version the driver supports --
+$DriverMaxCuda = $null
+try {
+    $smiOut = nvidia-smi 2>&1 | Out-String
+    if ($smiOut -match "CUDA Version:\s+([\d]+)\.([\d]+)") {
+        $DriverMaxCuda = "$($Matches[1]).$($Matches[2])"
+        Write-Host "   Driver supports up to CUDA $DriverMaxCuda" -ForegroundColor Gray
+    }
+} catch {}
+
+# -- Find a toolkit that's compatible with the driver --
+$IncompatibleToolkit = $null
+if ($DriverMaxCuda) {
+    $NvccPath = Find-Nvcc -MaxVersion $DriverMaxCuda
+    if ($NvccPath) {
+        Write-Host "   [OK] Found compatible CUDA Toolkit (nvcc: $NvccPath)" -ForegroundColor Green
+    } else {
+        # Check if there's an incompatible (too new) toolkit installed
+        $AnyNvcc = Find-Nvcc
+        if ($AnyNvcc) {
+            $NvccOut = & $AnyNvcc --version 2>&1 | Out-String
+            if ($NvccOut -match "release\s+([\d]+\.[\d]+)") {
+                $IncompatibleToolkit = $Matches[1]
+            }
+        }
+    }
+} else {
+    $NvccPath = Find-Nvcc
+}
+
+# -- If incompatible toolkit is blocking, tell user to uninstall it --
+if (-not $NvccPath -and $IncompatibleToolkit) {
+    Write-Host "" -ForegroundColor Red
+    Write-Host "========================================================================" -ForegroundColor Red
+    Write-Host "[ERROR] CUDA Toolkit $IncompatibleToolkit is installed but INCOMPATIBLE" -ForegroundColor Red
+    Write-Host "        with your NVIDIA driver (which supports up to CUDA $DriverMaxCuda)." -ForegroundColor Red
+    Write-Host "" -ForegroundColor Red
+    Write-Host "  This will cause 'failed to initialize CUDA' errors at runtime." -ForegroundColor Red
+    Write-Host "" -ForegroundColor Red
+    Write-Host "  To fix:" -ForegroundColor Yellow
+    Write-Host "    1. Open Control Panel -> Programs -> Uninstall a program" -ForegroundColor Yellow
+    Write-Host "    2. Uninstall 'NVIDIA CUDA Toolkit $IncompatibleToolkit'" -ForegroundColor Yellow
+    Write-Host "    3. Re-run setup.bat (it will install CUDA $DriverMaxCuda automatically)" -ForegroundColor Yellow
+    Write-Host "" -ForegroundColor Yellow
+    Write-Host "  Alternatively, update your NVIDIA driver to one that supports CUDA $IncompatibleToolkit." -ForegroundColor Gray
+    Write-Host "========================================================================" -ForegroundColor Red
+    exit 1
+}
+
+# -- No toolkit at all: install via winget --
+if (-not $NvccPath) {
+    Write-Host "CUDA toolkit (nvcc) not found -- installing via winget..." -ForegroundColor Yellow
+    $HasWinget = $null -ne (Get-Command winget -ErrorAction SilentlyContinue)
+    if ($HasWinget) {
+        if ($DriverMaxCuda) {
+            # Try descending compatible versions
+            $drMajor = [int]$DriverMaxCuda.Split('.')[0]
+            $drMinor = [int]$DriverMaxCuda.Split('.')[1]
+            for ($m = $drMinor; $m -ge 0; $m--) {
+                $ver = "$drMajor.$m"
+                Write-Host "   Trying CUDA Toolkit $ver via winget..." -ForegroundColor Cyan
+                $prevEAPCuda = $ErrorActionPreference
+                $ErrorActionPreference = "Continue"
+                winget install --id=Nvidia.CUDA --version=$ver -e --source winget --accept-package-agreements --accept-source-agreements 2>&1 | Out-Null
+                $ErrorActionPreference = $prevEAPCuda
+                Refresh-Environment
+                $NvccPath = Find-Nvcc -MaxVersion $DriverMaxCuda
+                if ($NvccPath) {
+                    Write-Host "   [OK] CUDA Toolkit $ver installed (nvcc: $NvccPath)" -ForegroundColor Green
+                    break
+                }
+            }
+        } else {
+            Write-Host "   Installing CUDA Toolkit (latest) via winget..." -ForegroundColor Cyan
+            winget install --id=Nvidia.CUDA -e --source winget --accept-package-agreements --accept-source-agreements
+            Refresh-Environment
+            $NvccPath = Find-Nvcc
+            if ($NvccPath) {
+                Write-Host "   [OK] CUDA Toolkit installed (nvcc: $NvccPath)" -ForegroundColor Green
+            }
+        }
+    }
+}
+
+if (-not $NvccPath) {
+    Write-Host "[ERROR] CUDA Toolkit (nvcc) is required but could not be found or installed." -ForegroundColor Red
+    if ($DriverMaxCuda) {
+        Write-Host "        Install CUDA Toolkit $DriverMaxCuda from https://developer.nvidia.com/cuda-toolkit-archive" -ForegroundColor Yellow
+    } else {
+        Write-Host "        Install CUDA Toolkit from https://developer.nvidia.com/cuda-downloads" -ForegroundColor Yellow
+    }
+    exit 1
+}
+
+# -- Set CUDA env vars so cmake AND MSBuild can find the toolkit --
+$CudaToolkitRoot = Split-Path (Split-Path $NvccPath -Parent) -Parent
+# CUDA_PATH: used by cmake's find_package(CUDAToolkit)
+[Environment]::SetEnvironmentVariable('CUDA_PATH', $CudaToolkitRoot, 'Process')
+# CudaToolkitDir: the MSBuild property that CUDA .targets checks directly
+# Trailing backslash required -- the .targets file appends subpaths to it
+[Environment]::SetEnvironmentVariable('CudaToolkitDir', "$CudaToolkitRoot\", 'Process')
+# Always persist CUDA_PATH to User registry so the compatible toolkit is used
+# in future sessions (overwrites any existing value pointing to a newer, incompatible version)
+[Environment]::SetEnvironmentVariable('CUDA_PATH', $CudaToolkitRoot, 'User')
+Write-Host "   Persisted CUDA_PATH=$CudaToolkitRoot to user environment" -ForegroundColor Gray
+# Ensure nvcc's bin dir is on PATH for this process
+$nvccBinDir = Split-Path $NvccPath -Parent
+if ($env:PATH -notlike "*$nvccBinDir*") {
+    [Environment]::SetEnvironmentVariable('PATH', "$nvccBinDir;$env:PATH", 'Process')
+}
+# Persist nvcc bin dir to User PATH so it works in new terminals
+$userPath = [Environment]::GetEnvironmentVariable('Path', 'User')
+if (-not $userPath -or $userPath -notlike "*$nvccBinDir*") {
+    if ($userPath) {
+        [Environment]::SetEnvironmentVariable('Path', "$nvccBinDir;$userPath", 'User')
+    } else {
+        [Environment]::SetEnvironmentVariable('Path', "$nvccBinDir", 'User')
+    }
+    Write-Host "   Persisted CUDA bin dir to user PATH" -ForegroundColor Gray
+}
+
+Write-Host "[OK] CUDA Toolkit: $NvccPath" -ForegroundColor Green
+Write-Host "   CUDA_PATH      = $CudaToolkitRoot" -ForegroundColor Gray
+Write-Host "   CudaToolkitDir = $CudaToolkitRoot\" -ForegroundColor Gray
+
+# Detect compute capability (used later for llama.cpp cmake)
+$CudaArch = Get-CudaComputeCapability
+if ($CudaArch) {
+    Write-Host "   Compute Capability = $($CudaArch.Insert($CudaArch.Length-1, '.')) (sm_$CudaArch)" -ForegroundColor Gray
+} else {
+    Write-Host "   [WARN] Could not detect compute capability -- cmake will use defaults" -ForegroundColor Yellow
+}
+
+# ============================================
+# 1f. Node.js / npm (always -- needed regardless of install method)
+# ============================================
+# setup.sh installs Node LTS (v22) via nvm. We enforce the same range here:
+# Node >= 20, npm >= 11.
+$NeedNode = $true
+try {
+    $NodeVersion = (node -v 2>$null)
+    $NpmVersion = (npm -v 2>$null)
+    if ($NodeVersion -and $NpmVersion) {
+        $NodeMajor = [int]($NodeVersion -replace 'v','').Split('.')[0]
+        $NpmMajor = [int]$NpmVersion.Split('.')[0]
+
+        if ($NodeMajor -ge 20 -and $NpmMajor -ge 11) {
+            Write-Host "[OK] Node $NodeVersion and npm $NpmVersion already meet requirements." -ForegroundColor Green
+            $NeedNode = $false
+        } else {
+            Write-Host "[WARN] Node $NodeVersion / npm $NpmVersion too old." -ForegroundColor Yellow
+        }
+    }
+} catch {
+    Write-Host "[WARN] Node/npm not found." -ForegroundColor Yellow
+}
+
+if ($NeedNode) {
+    Write-Host "Installing Node.js LTS via winget..." -ForegroundColor Cyan
+    try {
+        winget install OpenJS.NodeJS.LTS --source winget --accept-package-agreements --accept-source-agreements
+        Refresh-Environment
+    } catch {
+        Write-Host "[ERROR] Could not install Node.js automatically." -ForegroundColor Red
+        Write-Host "Please install Node.js >= 20 from https://nodejs.org/" -ForegroundColor Red
+        exit 1
+    }
+}
+
+Write-Host "[OK] Node $(node -v) | npm $(npm -v)" -ForegroundColor Green
+
+# ============================================
+# 1g. Python (>= 3.11 and < 3.14, matching setup.sh)
+# ============================================
+$HasPython = $null -ne (Get-Command python -ErrorAction SilentlyContinue)
+$PythonOk = $false
+
+if ($HasPython) {
+    $PyVer = python --version 2>&1
+    if ($PyVer -match "(\d+)\.(\d+)") {
+        $PyMajor = [int]$Matches[1]; $PyMinor = [int]$Matches[2]
+        if ($PyMajor -eq 3 -and $PyMinor -ge 11 -and $PyMinor -lt 14) {
+            Write-Host "[OK] Python $PyVer" -ForegroundColor Green
+            $PythonOk = $true
+        } else {
+            Write-Host "[ERROR] Python $PyVer is outside supported range (need >= 3.11 and < 3.14)." -ForegroundColor Red
+            Write-Host "        Install Python 3.12 from https://python.org/downloads/" -ForegroundColor Yellow
+            exit 1
+        }
+    }
+} else {
+    # No Python at all -- install 3.12
+    Write-Host "Python not found -- installing Python 3.12 via winget..." -ForegroundColor Yellow
+    $HasWinget = $null -ne (Get-Command winget -ErrorAction SilentlyContinue)
+    if ($HasWinget) {
+        winget install -e --id Python.Python.3.12 --source winget --accept-package-agreements --accept-source-agreements
+        Refresh-Environment
+    }
+    $HasPython = $null -ne (Get-Command python -ErrorAction SilentlyContinue)
+    if (-not $HasPython) {
+        Write-Host "[ERROR] Python could not be installed automatically." -ForegroundColor Red
+        Write-Host "        Install Python 3.12 from https://python.org/downloads/" -ForegroundColor Yellow
+        exit 1
+    }
+    Write-Host "[OK] Python $(python --version)" -ForegroundColor Green
+    $PythonOk = $true
+}
+
+Write-Host ""
+Write-Host "--- System prerequisites ready ---" -ForegroundColor Green
+Write-Host ""
+
+# ==========================================================================
+#  PHASE 2: Frontend build (skip if pip-installed -- already bundled)
+# ==========================================================================
+if ($IsPipInstall) {
+    Write-Host "[OK] Running from pip install - frontend already bundled, skipping build" -ForegroundColor Green
+} else {
+    Write-Host ""
+    Write-Host "Building frontend..." -ForegroundColor Cyan
+    # npm writes warnings to stderr; lower ErrorActionPreference so PS doesn't
+    # treat them as terminating errors (same pattern as the pip section below).
+    $prevEAP_npm = $ErrorActionPreference
+    $ErrorActionPreference = "Continue"
+    Push-Location $FrontendDir
+    # Remove stale node_modules and package-lock.json to avoid version conflicts
+    if (Test-Path "node_modules") { Remove-Item -Recurse -Force "node_modules" }
+    if (Test-Path "package-lock.json") { Remove-Item -Force "package-lock.json" }
+    npm install 2>&1 | Out-Null
+    if ($LASTEXITCODE -ne 0) {
+        Pop-Location
+        $ErrorActionPreference = $prevEAP_npm
+        Write-Host "[ERROR] npm install failed (exit code $LASTEXITCODE)" -ForegroundColor Red
+        Write-Host "   Try running 'npm install' manually in studio/frontend/ to see errors" -ForegroundColor Yellow
+        exit 1
+    }
+    npm run build 2>&1 | Out-Null
+    if ($LASTEXITCODE -ne 0) {
+        Pop-Location
+        $ErrorActionPreference = $prevEAP_npm
+        Write-Host "[ERROR] npm run build failed (exit code $LASTEXITCODE)" -ForegroundColor Red
+        exit 1
+    }
+    Pop-Location
+    $ErrorActionPreference = $prevEAP_npm
+    Write-Host "[OK] Frontend built to studio/frontend/dist" -ForegroundColor Green
+}
+
+# ==========================================================================
+#  PHASE 3: Python environment + dependencies
+# ==========================================================================
+Write-Host ""
+Write-Host "Setting up Python environment..." -ForegroundColor Cyan
+
+# Find Python
+$PythonCmd = $null
+foreach ($candidate in @("python3.12", "python3.11", "python3.10", "python3.9", "python3", "python")) {
+    try {
+        $ver = & $candidate --version 2>&1
+        if ($ver -match 'Python 3\.(\d+)') {
+            $minor = [int]$Matches[1]
+            if ($minor -le 12) {
+                $PythonCmd = $candidate
+                break
+            }
+        }
+    } catch { }
+}
+
+if (-not $PythonCmd) {
+    Write-Host "[ERROR] No Python <= 3.12 found." -ForegroundColor Red
+    exit 1
+}
+
+Write-Host "[OK] Using $PythonCmd ($(& $PythonCmd --version 2>&1))" -ForegroundColor Green
+
+# Always create a .venv for isolation -- even for pip installs.
+# Created in the current working directory (where user ran the command).
+$VenvDir = Join-Path (Get-Location) ".venv"
+if (-not (Test-Path $VenvDir)) {
+    Write-Host "   Creating virtual environment at $VenvDir..." -ForegroundColor Cyan
+    & $PythonCmd -m venv $VenvDir
+} else {
+    Write-Host "   Reusing existing virtual environment at $VenvDir" -ForegroundColor Green
+}
+
+# pip and python write to stderr even on success (progress bars, warnings).
+# With $ErrorActionPreference = "Stop" (set at top of script), PS 5.1
+# converts stderr lines into terminating ErrorRecords, breaking output.
+# Lower to "Continue" for the pip/python section.
+$prevEAP = $ErrorActionPreference
+$ErrorActionPreference = "Continue"
+
+$ActivateScript = Join-Path $VenvDir "Scripts\Activate.ps1"
+. $ActivateScript
+pip install --upgrade pip 2>&1 | Out-Null
+
+# if (-not $IsPipInstall) {
+#     # Running from repo: copy requirements and do editable install
+#     $RepoRoot = (Resolve-Path (Join-Path $ScriptDir "..\..")).Path
+#     $ReqsSrc = Join-Path $RepoRoot "backend\requirements"
+#     $ReqsDst = Join-Path $PackageDir "requirements"
+#     if (-not (Test-Path $ReqsDst)) { New-Item -ItemType Directory -Path $ReqsDst | Out-Null }
+#     Copy-Item (Join-Path $ReqsSrc "*.txt") $ReqsDst -Force
+
+#     Write-Host "   Installing CLI entry point..." -ForegroundColor Cyan
+#     pip install -e $RepoRoot 2>&1 | Out-Null
+# } else {
+#     # Running from pip install: the package is in system Python but not in
+#     # the fresh .venv. Install it so run_install() can find its modules
+#     # and bundled requirements files.
+#     Write-Host "   Installing package into venv..." -ForegroundColor Cyan
+#     pip install unsloth-roland-test 2>&1 | Out-Null
+# }
+
+# Pre-install PyTorch with CUDA support.
+# On Windows, the default PyPI torch wheel is CPU-only.
+# We need PyTorch's CUDA index to get GPU-enabled wheels.
+# PyTorch bundles its own CUDA runtime, so this works regardless
+# of whether the CUDA Toolkit is installed yet.
+# The CUDA tag is chosen based on the driver's max supported CUDA version.
+
+# Windows MAX_PATH (260 chars) causes Triton kernel compilation to fail because
+# the auto-generated filenames are extremely long. Use a short cache directory.
+$TorchCacheDir = "C:\tc"
+if (-not (Test-Path $TorchCacheDir)) { New-Item -ItemType Directory -Path $TorchCacheDir -Force | Out-Null }
+$env:TORCHINDUCTOR_CACHE_DIR = $TorchCacheDir
+[Environment]::SetEnvironmentVariable('TORCHINDUCTOR_CACHE_DIR', $TorchCacheDir, 'User')
+Write-Host "[OK] TORCHINDUCTOR_CACHE_DIR set to $TorchCacheDir (avoids MAX_PATH issues)" -ForegroundColor Green
+
+$CuTag = Get-PytorchCudaTag
+Write-Host "   Installing PyTorch with CUDA support ($CuTag)..." -ForegroundColor Cyan
+pip install torch torchvision torchaudio --index-url "https://download.pytorch.org/whl/$CuTag" 2>&1 | Out-Null
+
+# Ordered heavy dependency installation — shared cross-platform script
+Write-Host "   Running ordered dependency installation..." -ForegroundColor Cyan
+python "$PSScriptRoot\install_python_stack.py"
+# Restore ErrorActionPreference after pip/python work
+$ErrorActionPreference = $prevEAP
+
+# ==========================================================================
+#  PHASE 3.5: Install OpenSSL dev (for HTTPS support in llama-server)
+# ==========================================================================
+# llama-server needs OpenSSL to download models from HuggingFace via -hf.
+# ShiningLight.OpenSSL.Dev includes headers + libs that cmake can find.
+$OpenSslAvailable = $false
+
+# Check if OpenSSL dev is already installed (look for include dir)
+$OpenSslRoots = @(
+    'C:\Program Files\OpenSSL-Win64',
+    'C:\Program Files\OpenSSL',
+    'C:\OpenSSL-Win64'
+)
+$OpenSslRoot = $null
+foreach ($root in $OpenSslRoots) {
+    if (Test-Path (Join-Path $root 'include\openssl\ssl.h')) {
+        $OpenSslRoot = $root
+        break
+    }
+}
+
+if ($OpenSslRoot) {
+    $OpenSslAvailable = $true
+    Write-Host "[OK] OpenSSL dev found at $OpenSslRoot" -ForegroundColor Green
+} else {
+    Write-Host "" 
+    Write-Host "Installing OpenSSL dev (for HTTPS in llama-server)..." -ForegroundColor Cyan
+    $HasWinget = $null -ne (Get-Command winget -ErrorAction SilentlyContinue)
+    if ($HasWinget) {
+        winget install -e --id ShiningLight.OpenSSL.Dev --accept-package-agreements --accept-source-agreements
+        # Re-check after install
+        foreach ($root in $OpenSslRoots) {
+            if (Test-Path (Join-Path $root 'include\openssl\ssl.h')) {
+                $OpenSslRoot = $root
+                $OpenSslAvailable = $true
+                Write-Host "[OK] OpenSSL dev installed at $OpenSslRoot" -ForegroundColor Green
+                break
+            }
+        }
+    }
+    if (-not $OpenSslAvailable) {
+        Write-Host "[WARN] OpenSSL dev not available -- llama-server will be built without HTTPS" -ForegroundColor Yellow
+    }
+}
+
+# ==========================================================================
+#  PHASE 4: Build llama.cpp with CUDA for GGUF inference + export
+# ==========================================================================
+# Builds at ~/.unsloth/llama.cpp — a single shared location under the user's
+# home directory. This is used by both the inference server and the GGUF
+# export pipeline (unsloth-zoo).
+# We build:
+#   - llama-server:   for GGUF model inference (with HTTPS if OpenSSL available)
+#   - llama-quantize: for GGUF export quantization
+# Prerequisites (git, cmake, VS Build Tools, CUDA Toolkit) already installed in Phase 1.
+$UnslothHome = Join-Path $env:USERPROFILE ".unsloth"
+if (-not (Test-Path $UnslothHome)) { New-Item -ItemType Directory -Force $UnslothHome | Out-Null }
+$LlamaCppDir = Join-Path $UnslothHome "llama.cpp"
+$BuildDir = Join-Path $LlamaCppDir "build"
+$LlamaServerBin = Join-Path $BuildDir "bin\Release\llama-server.exe"
+
+if (Test-Path $LlamaServerBin) {
+    Write-Host ""
+    Write-Host "[OK] llama-server already exists at $LlamaServerBin" -ForegroundColor Green
+} else {
+    Write-Host ""
+    Write-Host "Building llama.cpp with CUDA support..." -ForegroundColor Cyan
+    Write-Host "   This typically takes 5-10 minutes on first build." -ForegroundColor Gray
+    Write-Host ""
+
+    # Start total build timer
+    $totalSw = [System.Diagnostics.Stopwatch]::StartNew()
+
+    # Native commands (git, cmake) write to stderr even on success.
+    # With $ErrorActionPreference = "Stop" (set at top of script), PS 5.1
+    # converts stderr lines into terminating ErrorRecords, breaking output.
+    # Lower to "Continue" for the build section.
+    $prevEAP = $ErrorActionPreference
+    $ErrorActionPreference = "Continue"
+
+    $BuildOk = $true
+    $FailedStep = ""
+
+    # -- Step A: Clone or pull llama.cpp --
+
+    if (Test-Path (Join-Path $LlamaCppDir ".git")) {
+        Write-Host "   llama.cpp repo already cloned, pulling latest..." -ForegroundColor Gray
+        git -C $LlamaCppDir pull
+        if ($LASTEXITCODE -ne 0) {
+            Write-Host "   [WARN] git pull failed -- using existing source" -ForegroundColor Yellow
+        }
+    } else {
+        Write-Host "   Cloning llama.cpp..." -ForegroundColor Gray
+        if (Test-Path $LlamaCppDir) { Remove-Item -Recurse -Force $LlamaCppDir }
+        git clone --depth 1 https://github.com/ggml-org/llama.cpp.git $LlamaCppDir
+        if ($LASTEXITCODE -ne 0) {
+            $BuildOk = $false
+            $FailedStep = "git clone"
+        }
+    }
+
+    # -- Step B: cmake configure (CUDA + Unsloth flags) --
+    if ($BuildOk) {
+        Write-Host ""
+        Write-Host "--- cmake configure ---" -ForegroundColor Cyan
+
+        $CmakeArgs = @(
+            '-S', $LlamaCppDir,
+            '-B', $BuildDir,
+            '-G', $CmakeGenerator,
+            '-Wno-dev'
+        )
+        # Tell cmake exactly where VS is (bypasses registry lookup)
+        if ($VsInstallPath) {
+            $CmakeArgs += "-DCMAKE_GENERATOR_INSTANCE=$VsInstallPath"
+        }
+        # Common flags
+        $CmakeArgs += '-DBUILD_SHARED_LIBS=OFF'
+        # HTTPS support via OpenSSL
+        if ($OpenSslAvailable -and $OpenSslRoot) {
+            $CmakeArgs += "-DOPENSSL_ROOT_DIR=$OpenSslRoot"
+            $CmakeArgs += '-DLLAMA_OPENSSL=ON'
+        } else {
+            $CmakeArgs += '-DLLAMA_CURL=OFF'
+        }
+        $CmakeArgs += '-DCMAKE_EXE_LINKER_FLAGS=/NODEFAULTLIB:LIBCMT'
+        # CUDA flags (Unsloth-aligned)
+        $CmakeArgs += '-DGGML_CUDA=ON'
+        $CmakeArgs += "-DCUDAToolkit_ROOT=$CudaToolkitRoot"
+        $CmakeArgs += "-DCMAKE_CUDA_COMPILER=$NvccPath"
+        $CmakeArgs += '-DGGML_CUDA_FA_ALL_QUANTS=ON'
+        $CmakeArgs += '-DGGML_CUDA_F16=OFF'
+        $CmakeArgs += '-DGGML_CUDA_GRAPHS=OFF'
+        $CmakeArgs += '-DGGML_CUDA_FORCE_CUBLAS=OFF'
+        $CmakeArgs += '-DGGML_CUDA_PEER_MAX_BATCH_SIZE=8192'
+        if ($CudaArch) {
+            $CmakeArgs += "-DCMAKE_CUDA_ARCHITECTURES=$CudaArch"
+        }
+
+        Write-Host "   cmake args:" -ForegroundColor Gray
+        foreach ($arg in $CmakeArgs) {
+            Write-Host "     $arg" -ForegroundColor Gray
+        }
+        Write-Host ""
+
+        cmake @CmakeArgs
+        if ($LASTEXITCODE -ne 0) {
+            $BuildOk = $false
+            $FailedStep = "cmake configure"
+        }
+    }
+
+    # -- Step C: Build llama-server --
+    $NumCpu = [Environment]::ProcessorCount
+    if ($NumCpu -lt 1) { $NumCpu = 4 }
+
+    if ($BuildOk) {
+        Write-Host ""
+        Write-Host "--- cmake build (llama-server) ---" -ForegroundColor Cyan
+        Write-Host "   Parallel jobs: $NumCpu" -ForegroundColor Gray
+        Write-Host ""
+
+        cmake --build $BuildDir --config Release --target llama-server -j $NumCpu
+        if ($LASTEXITCODE -ne 0) {
+            $BuildOk = $false
+            $FailedStep = "cmake build (llama-server)"
+        }
+    }
+
+    # -- Step D: Build llama-quantize (optional, best-effort) --
+    if ($BuildOk) {
+        Write-Host ""
+        Write-Host "--- cmake build (llama-quantize) ---" -ForegroundColor Cyan
+        cmake --build $BuildDir --config Release --target llama-quantize -j $NumCpu
+        if ($LASTEXITCODE -ne 0) {
+            Write-Host "   [WARN] llama-quantize build failed (GGUF export may be unavailable)" -ForegroundColor Yellow
+        }
+    }
+
+    # Restore ErrorActionPreference
+    $ErrorActionPreference = $prevEAP
+
+    # Stop timer
+    $totalSw.Stop()
+    $totalMin = [math]::Floor($totalSw.Elapsed.TotalMinutes)
+    $totalSec = [math]::Round($totalSw.Elapsed.TotalSeconds % 60, 1)
+
+    # -- Summary --
+    Write-Host ""
+    if ($BuildOk -and (Test-Path $LlamaServerBin)) {
+        Write-Host "[OK] llama-server built at $LlamaServerBin" -ForegroundColor Green
+        $QuantizeBin = Join-Path $BuildDir "bin\Release\llama-quantize.exe"
+        if (Test-Path $QuantizeBin) {
+            Write-Host "[OK] llama-quantize available for GGUF export" -ForegroundColor Green
+        }
+        Write-Host "   Build time: ${totalMin}m ${totalSec}s" -ForegroundColor Cyan
+    } else {
+        # Check alternate paths (some cmake generators don't use Release subdir)
+        $altBin = Join-Path $BuildDir "bin\llama-server.exe"
+        if ($BuildOk -and (Test-Path $altBin)) {
+            Write-Host "[OK] llama-server built at $altBin" -ForegroundColor Green
+            Write-Host "   Build time: ${totalMin}m ${totalSec}s" -ForegroundColor Cyan
+        } else {
+            Write-Host "[FAILED] llama.cpp build failed at step: $FailedStep (${totalMin}m ${totalSec}s)" -ForegroundColor Red
+            Write-Host "         To retry: delete $LlamaCppDir and re-run setup." -ForegroundColor Yellow
+            exit 1
+        }
+    }
+}
+
+# ============================================
+# Add shell aliases (PowerShell profile + cmd batch files)
+# ============================================
+Write-Host ""
+$RepoDir = $PSScriptRoot
+$VenvPython = Join-Path $RepoDir ".venv\Scripts\python.exe"
+$CliScript = Join-Path $RepoDir "cli.py"
+$FrontendDist = Join-Path $RepoDir "studio\frontend\dist"
+$AliasAdded = $false
+
+# --- PowerShell profile: add functions ---
+$ProfileDir = Split-Path $PROFILE -Parent
+if (-not (Test-Path $ProfileDir)) { New-Item -ItemType Directory -Path $ProfileDir -Force | Out-Null }
+if (-not (Test-Path $PROFILE)) { New-Item -ItemType File -Path $PROFILE -Force | Out-Null }
+
+if (-not (Select-String -Path $PROFILE -Pattern "unsloth-studio" -Quiet -ErrorAction SilentlyContinue)) {
+    $block = @"
+
+# Unsloth Studio launcher
+function unsloth-studio { & "$VenvPython" "$CliScript" studio -f "$FrontendDist" @args }
+function unsloth-ui     { & "$VenvPython" "$CliScript" studio -f "$FrontendDist" @args }
+"@
+    Add-Content -Path $PROFILE -Value $block
+    Write-Host "[OK] Aliases 'unsloth-studio' and 'unsloth-ui' added to $PROFILE" -ForegroundColor Green
+    $AliasAdded = $true
+} else {
+    Write-Host "[OK] Aliases 'unsloth-studio' and 'unsloth-ui' already exist in $PROFILE" -ForegroundColor Green
+}
+
+# --- cmd.exe: create batch files and ensure they're on PATH ---
+$BatDir = Join-Path $RepoDir ".venv\Scripts"
+foreach ($name in @("unsloth-studio", "unsloth-ui")) {
+    $batPath = Join-Path $BatDir "$name.bat"
+    if (-not (Test-Path $batPath)) {
+        Set-Content -Path $batPath -Value "@echo off`r`n`"$VenvPython`" `"$CliScript`" studio -f `"$FrontendDist`" %*"
+    }
+}
+# Persist .venv\Scripts to User PATH so commands work in new cmd.exe terminals without activation
+$userPath = [Environment]::GetEnvironmentVariable('Path', 'User')
+if (-not $userPath -or $userPath -notlike "*$BatDir*") {
+    if ($userPath) {
+        [Environment]::SetEnvironmentVariable('Path', "$BatDir;$userPath", 'User')
+    } else {
+        [Environment]::SetEnvironmentVariable('Path', "$BatDir", 'User')
+    }
+    Write-Host "   Persisted $BatDir to User PATH" -ForegroundColor Gray
+}
+Write-Host "[OK] Batch launchers created (works from any new cmd.exe or PowerShell)" -ForegroundColor Green
+
+# ============================================
+# Done
+# ============================================
+Write-Host ""
+Write-Host "+===============================================+" -ForegroundColor Green
+Write-Host "|           Setup Complete!                     |" -ForegroundColor Green
+Write-Host "|                                               |" -ForegroundColor Green
+Write-Host "|  IMPORTANT: Open a NEW terminal, then run:    |" -ForegroundColor Yellow
+Write-Host "|                                               |" -ForegroundColor Green
+Write-Host "|    unsloth-studio -H 0.0.0.0 -p 8000         |" -ForegroundColor Green
+Write-Host "|                                               |" -ForegroundColor Green
+Write-Host "+===============================================+" -ForegroundColor Green
\ No newline at end of file
diff --git a/setup.sh b/setup.sh
index 9cc6f527bd..07ea131125 100755
--- a/setup.sh
+++ b/setup.sh
@@ -170,36 +170,7 @@ SINGLE_ENV_DATA_DESIGNER_DEPS="$REQ_ROOT/single-env/data-designer-deps.txt"
 SINGLE_ENV_PATCH="$REQ_ROOT/single-env/patch_metadata.py"
 
 install_python_stack() {
-    run_quiet "pip upgrade" pip install --upgrade pip
-    echo "   Installing unsloth-zoo + unsloth..."
-    run_quiet "pip install unsloth" pip install --no-cache-dir -c "$SINGLE_ENV_CONSTRAINTS" -r "$REQ_ROOT/base.txt"
-    echo "   Installing additional unsloth dependencies..."
-    run_quiet "pip install extras" pip install --no-cache-dir -c "$SINGLE_ENV_CONSTRAINTS" -r "$REQ_ROOT/extras.txt"
-    run_quiet "pip install torchao+transformers" pip install --force-reinstall --no-cache-dir -c "$SINGLE_ENV_CONSTRAINTS" -r "$REQ_ROOT/overrides.txt"
-    run_quiet "pip install triton_kernels" pip install --no-deps --no-cache-dir -r "$REQ_ROOT/triton-kernels.txt"
-    # Patch: override llama_cpp.py with fix from unsloth-zoo branch
-    LLAMA_CPP_DST="$(pip show unsloth-zoo | grep -i '^Location:' | awk '{print $2}')/unsloth_zoo/llama_cpp.py"
-    curl -sSL "https://raw.githubusercontent.com/unslothai/unsloth-zoo/refs/heads/main/unsloth_zoo/llama_cpp.py" \
-        -o "$LLAMA_CPP_DST"
-    # Patch: override vision.py with fix from unsloth PR: https://github.com/unslothai/unsloth/pull/4091 until next pypi release
-    VISION_DST="$(pip show unsloth | grep -i '^Location:' | awk '{print $2}')/unsloth/models/vision.py"
-    curl -sSL "https://raw.githubusercontent.com/unslothai/unsloth/80e0108a684c882965a02a8ed851e3473c1145ab/unsloth/models/vision.py" \
-        -o "$VISION_DST"
-    echo "   Installing studio dependencies..."
-    run_quiet "pip install studio" pip install --no-cache-dir -c "$SINGLE_ENV_CONSTRAINTS" -r "$REQ_ROOT/studio.txt"
-    echo "   Installing data-designer dependencies..."
-    run_quiet "pip install data-designer deps" pip install --no-cache-dir -c "$SINGLE_ENV_CONSTRAINTS" -r "$SINGLE_ENV_DATA_DESIGNER_DEPS"
-    echo "   Installing data-designer..."
-    run_quiet "pip install data-designer" pip install --no-cache-dir --no-deps -c "$SINGLE_ENV_CONSTRAINTS" -r "$SINGLE_ENV_DATA_DESIGNER"
-    # Colab's bundled IPython 7.34 requires jedi but doesn't ship it
-    run_quiet "pip install jedi" pip install --no-cache-dir jedi
-    run_quiet "patch single-env metadata" python "$SINGLE_ENV_PATCH"
-    # pip check can flag minor transitive-dependency version mismatches that
-    # don't actually break anything.  Warn instead of aborting.
-    if ! pip check > /dev/null 2>&1; then
-        echo "⚠️  pip check reports dependency conflicts (safe to ignore)"
-    fi
-    echo "✅ Python dependencies installed"
+    python "$SCRIPT_DIR/install_python_stack.py"
 }
 
 if [ "$IS_COLAB" = true ]; then
@@ -226,11 +197,14 @@ else
 fi
 
 # ── 8. Build llama.cpp binaries for GGUF inference + export ──
-# Builds in-tree at $REPO/llama.cpp/. This directory is shared with
-# unsloth-zoo's GGUF export pipeline. We build:
+# Builds at ~/.unsloth/llama.cpp — a single shared location under the user's
+# home directory. This is used by both the inference server and the GGUF
+# export pipeline (unsloth-zoo).
 #   - llama-server: for GGUF model inference
 #   - llama-quantize: for GGUF export quantization (symlinked to root for check_llama_cpp())
-LLAMA_CPP_DIR="$SCRIPT_DIR/llama.cpp"
+UNSLOTH_HOME="$HOME/.unsloth"
+mkdir -p "$UNSLOTH_HOME"
+LLAMA_CPP_DIR="$UNSLOTH_HOME/llama.cpp"
 LLAMA_SERVER_BIN="$LLAMA_CPP_DIR/build/bin/llama-server"
 rm -rf "$LLAMA_CPP_DIR"
 {
diff --git a/studio/backend/core/export/export.py b/studio/backend/core/export/export.py
index bc4e267f75..3d3db2d560 100644
--- a/studio/backend/core/export/export.py
+++ b/studio/backend/core/export/export.py
@@ -418,9 +418,8 @@ class ExportBackend:
                 pre_existing_ggufs = set(glob.glob(os.path.join(cwd, "*.gguf")))
 
                 # Pass absolute path — no os.chdir needed.
-                # unsloth saves intermediate HF model files into model_save_path,
-                # while check_llama_cpp("llama.cpp") resolves against cwd (repo root)
-                # where setup.sh already built llama.cpp with quantizer.
+                # unsloth saves intermediate HF model files into model_save_path.
+                # unsloth-zoo's check_llama_cpp() uses ~/.unsloth/llama.cpp by default.
                 model_save_path = os.path.join(abs_save_dir, "model")
                 self.current_model.save_pretrained_gguf(
                     model_save_path,
diff --git a/studio/backend/core/inference/llama_cpp.py b/studio/backend/core/inference/llama_cpp.py
index b7b87e9cfb..f47b9132db 100644
--- a/studio/backend/core/inference/llama_cpp.py
+++ b/studio/backend/core/inference/llama_cpp.py
@@ -76,33 +76,83 @@ class LlamaCppBackend:
         Locate the llama-server binary.
 
         Search order:
-        1. LLAMA_SERVER_PATH environment variable
-        2. ./llama.cpp/build/bin/llama-server  (built by setup.sh in-tree)
-        3. llama-server on PATH  (system install)
-        4. ./bin/llama-server  (legacy: extracted binary)
+        1.  LLAMA_SERVER_PATH environment variable (direct path to binary)
+        1b. UNSLOTH_LLAMA_CPP_PATH env var (custom llama.cpp install dir)
+        2.  ~/.unsloth/llama.cpp/llama-server        (make build, root dir)
+        3.  ~/.unsloth/llama.cpp/build/bin/llama-server  (cmake build, Linux)
+        4.  ~/.unsloth/llama.cpp/build/bin/Release/llama-server.exe  (cmake build, Windows)
+        5.  ./llama.cpp/llama-server                 (legacy: make build, root dir)
+        6.  ./llama.cpp/build/bin/llama-server        (legacy: cmake in-tree build)
+        7.  llama-server on PATH                     (system install)
+        8.  ./bin/llama-server                       (legacy: extracted binary)
         """
         import os
+        import sys
 
-        # 1. Env var
+        binary_name = "llama-server.exe" if sys.platform == "win32" else "llama-server"
+
+        # 1. Env var — direct path to binary
         env_path = os.environ.get("LLAMA_SERVER_PATH")
         if env_path and Path(env_path).is_file():
             return env_path
 
-        # Project root: llama_cpp.py → inference/ → core/ → backend/ → studio/ → root
-        project_root = Path(__file__).resolve().parents[4]
+        # 1b. UNSLOTH_LLAMA_CPP_PATH — custom llama.cpp install directory
+        custom_llama_cpp = os.environ.get("UNSLOTH_LLAMA_CPP_PATH")
+        if custom_llama_cpp:
+            custom_dir = Path(custom_llama_cpp)
+            # Root dir (make builds)
+            root_bin = custom_dir / binary_name
+            if root_bin.is_file():
+                return str(root_bin)
+            # build/bin/ (cmake builds on Linux)
+            cmake_bin = custom_dir / "build" / "bin" / binary_name
+            if cmake_bin.is_file():
+                return str(cmake_bin)
+            # build/bin/Release/ (cmake builds on Windows)
+            if sys.platform == "win32":
+                win_bin = custom_dir / "build" / "bin" / "Release" / binary_name
+                if win_bin.is_file():
+                    return str(win_bin)
 
-        # 2. In-tree llama.cpp build (setup.sh builds here)
-        build_path = project_root / "llama.cpp" / "build" / "bin" / "llama-server"
+        # 2–4. ~/.unsloth/llama.cpp (primary — setup.sh / setup.ps1 build here)
+        unsloth_home = Path.home() / ".unsloth" / "llama.cpp"
+        # Root dir (make builds copy binaries here)
+        home_root = unsloth_home / binary_name
+        if home_root.is_file():
+            return str(home_root)
+        # build/bin/ (cmake builds on Linux)
+        home_linux = unsloth_home / "build" / "bin" / binary_name
+        if home_linux.is_file():
+            return str(home_linux)
+
+        # 3. Windows MSVC build has Release subdir
+        if sys.platform == "win32":
+            home_win = unsloth_home / "build" / "bin" / "Release" / binary_name
+            if home_win.is_file():
+                return str(home_win)
+
+        # 5–6. Legacy: in-tree build (older setup.sh / setup.ps1 versions)
+        project_root = Path(__file__).resolve().parents[4]
+        # Root dir (make builds)
+        root_path = project_root / "llama.cpp" / binary_name
+        if root_path.is_file():
+            return str(root_path)
+        # build/bin/ (cmake builds)
+        build_path = project_root / "llama.cpp" / "build" / "bin" / binary_name
         if build_path.is_file():
             return str(build_path)
+        if sys.platform == "win32":
+            win_path = project_root / "llama.cpp" / "build" / "bin" / "Release" / binary_name
+            if win_path.is_file():
+                return str(win_path)
 
-        # 3. System PATH
+        # 7. System PATH
         system_path = shutil.which("llama-server")
         if system_path:
             return system_path
 
-        # 4. Legacy: extracted to bin/
-        bin_path = project_root / "bin" / "llama-server"
+        # 8. Legacy: extracted to bin/
+        bin_path = project_root / "bin" / binary_name
         if bin_path.is_file():
             return str(bin_path)
 
@@ -184,16 +234,58 @@ class LlamaCppBackend:
 
             # Build command based on mode
             if hf_repo:
-                hf_spec = f"{hf_repo}:{hf_variant}" if hf_variant else hf_repo
+                # Download the GGUF file ourselves using huggingface_hub
+                # (llama-server's -hf flag requires HTTPS/curl which may not
+                #  be available, e.g. Windows builds with -DLLAMA_CURL=OFF)
+                try:
+                    from huggingface_hub import hf_hub_download
+                except ImportError:
+                    raise RuntimeError(
+                        "huggingface_hub is required for HF model loading. "
+                        "Install it with: pip install huggingface_hub"
+                    )
+
+                # Determine the filename from the variant (e.g., "Q4_K_M" -> find matching file)
+                gguf_filename = None
+                if hf_variant:
+                    # Try common naming patterns
+                    try:
+                        from huggingface_hub import list_repo_files
+                        files = list_repo_files(hf_repo, token=hf_token)
+                        variant_lower = hf_variant.lower()
+                        for f in files:
+                            if f.endswith(".gguf") and variant_lower in f.lower():
+                                gguf_filename = f
+                                break
+                    except Exception as e:
+                        logger.warning(f"Could not list repo files: {e}")
+
+                    if not gguf_filename:
+                        # Fallback: construct common filename pattern
+                        # e.g., "unsloth/gemma-3-4b-it-GGUF" + "Q4_K_M" -> try model name
+                        repo_name = hf_repo.split("/")[-1].replace("-GGUF", "")
+                        gguf_filename = f"{repo_name}-{hf_variant}.gguf"
+
+                logger.info(f"Downloading GGUF: {hf_repo}/{gguf_filename}")
+                try:
+                    local_path = hf_hub_download(
+                        repo_id=hf_repo,
+                        filename=gguf_filename,
+                        token=hf_token,
+                    )
+                except Exception as e:
+                    raise RuntimeError(
+                        f"Failed to download GGUF file '{gguf_filename}' from {hf_repo}: {e}"
+                    )
+
+                logger.info(f"GGUF downloaded to: {local_path}")
                 cmd = [
                     binary,
-                    "-hf", hf_spec,
+                    "-m", local_path,
                     "--port", str(self._port),
                     "-c", str(n_ctx),
                     "-ngl", str(n_gpu_layers),
                 ]
-                if hf_token:
-                    cmd.extend(["--hf-token", hf_token])
             elif gguf_path:
                 if not Path(gguf_path).is_file():
                     raise FileNotFoundError(f"GGUF file not found: {gguf_path}")
@@ -220,13 +312,31 @@ class LlamaCppBackend:
 
             logger.info(f"Starting llama-server: {' '.join(cmd)}")
 
-            # Set LD_LIBRARY_PATH so llama-server can find its shared libs
-            # (libmtmd.so, libllama.so, etc.) which live next to the binary
+            # Set library paths so llama-server can find its shared libs and CUDA DLLs
             import os
+            import sys
             env = os.environ.copy()
             binary_dir = str(Path(binary).parent)
-            existing_ld = env.get("LD_LIBRARY_PATH", "")
-            env["LD_LIBRARY_PATH"] = f"{binary_dir}:{existing_ld}" if existing_ld else binary_dir
+
+            if sys.platform == "win32":
+                # On Windows, CUDA DLLs (cublas64_12.dll, cudart64_12.dll, etc.)
+                # must be on PATH. Add CUDA_PATH\bin if available.
+                path_dirs = [binary_dir]
+                cuda_path = os.environ.get("CUDA_PATH", "")
+                if cuda_path:
+                    cuda_bin = os.path.join(cuda_path, "bin")
+                    if os.path.isdir(cuda_bin):
+                        path_dirs.append(cuda_bin)
+                    # Some CUDA installs put DLLs in bin\x64
+                    cuda_bin_x64 = os.path.join(cuda_path, "bin", "x64")
+                    if os.path.isdir(cuda_bin_x64):
+                        path_dirs.append(cuda_bin_x64)
+                existing_path = env.get("PATH", "")
+                env["PATH"] = ";".join(path_dirs) + ";" + existing_path
+            else:
+                # Linux: set LD_LIBRARY_PATH for shared libs next to the binary
+                existing_ld = env.get("LD_LIBRARY_PATH", "")
+                env["LD_LIBRARY_PATH"] = f"{binary_dir}:{existing_ld}" if existing_ld else binary_dir
 
             self._stdout_lines = []
             self._process = subprocess.Popen(
@@ -249,9 +359,8 @@ class LlamaCppBackend:
             self._is_vision = is_vision
             self._model_identifier = model_identifier
 
-            # HF mode: llama-server downloads before becoming healthy — need longer timeout
-            timeout = 600.0 if hf_repo else 120.0
-            if not self._wait_for_health(timeout=timeout):
+            # Wait for llama-server to become healthy
+            if not self._wait_for_health(timeout=120.0):
                 self._kill_process()
                 raise RuntimeError(
                     "llama-server failed to start. "
diff --git a/studio/backend/utils/hardware/hardware.py b/studio/backend/utils/hardware/hardware.py
index b885e130d5..fd43e620bb 100644
--- a/studio/backend/utils/hardware/hardware.py
+++ b/studio/backend/utils/hardware/hardware.py
@@ -423,6 +423,11 @@ def safe_num_proc(desired: Optional[int] = None) -> int:
     """
     Return a safe ``num_proc`` for ``dataset.map()`` calls.
 
+    On Windows, always returns 1 because Python uses ``spawn`` instead of
+    ``fork`` for multiprocessing — the overhead of re-importing torch,
+    transformers, unsloth etc. per worker is typically slower than
+    single-process for normal dataset sizes.
+
     On multi-GPU machines the NVIDIA driver spawns extra background threads,
     making ``os.fork()`` prone to deadlocks when many workers are created.
     This helper caps ``num_proc`` to 4 on such machines.
@@ -438,6 +443,12 @@ def safe_num_proc(desired: Optional[int] = None) -> int:
         A safe integer ≥ 1.
     """
     import os
+    import sys
+
+    # Windows uses 'spawn' for multiprocessing — the overhead of re-importing
+    # torch/transformers/unsloth per worker is typically slower than single-process.
+    if sys.platform == "win32":
+        return 1
 
     if desired is None or not isinstance(desired, int):
         desired = max(1, os.cpu_count() // 3)
diff --git a/test_llama_cpp.ps1 b/test_llama_cpp.ps1
new file mode 100644
index 0000000000..b98177eac6
--- /dev/null
+++ b/test_llama_cpp.ps1
@@ -0,0 +1,234 @@
+<#
+.SYNOPSIS
+    Test script for llama.cpp compilation and binary validation on Windows.
+    Verifies that llama-server was built with CUDA support and can start.
+
+.USAGE
+    .\test_llama_cpp.ps1
+    .\test_llama_cpp.ps1 -BinaryPath "C:\path\to\llama-server.exe"
+#>
+param(
+    [string]$BinaryPath = ""
+)
+
+$ErrorActionPreference = "Continue"
+
+Write-Host ""
+Write-Host "============================================" -ForegroundColor Cyan
+Write-Host "  llama.cpp Windows Build Test" -ForegroundColor Cyan
+Write-Host "============================================" -ForegroundColor Cyan
+Write-Host ""
+
+# -- Step 1: Locate the binary ------------------------------------------
+Write-Host "1. Locating llama-server binary..." -ForegroundColor Yellow
+
+$SearchPaths = @()
+
+if ($BinaryPath) {
+    $SearchPaths += $BinaryPath
+}
+
+# Add all known locations
+$RepoRoot = $PSScriptRoot
+$SearchPaths += Join-Path $RepoRoot "llama.cpp\build\bin\Release\llama-server.exe"
+$SearchPaths += Join-Path $RepoRoot "llama.cpp\build\bin\llama-server.exe"
+# Legacy: older setup.ps1 built under ~/.unsloth
+$SearchPaths += Join-Path $env:USERPROFILE ".unsloth\llama.cpp\build\bin\Release\llama-server.exe"
+
+# Check LLAMA_SERVER_PATH env var
+$envPath = $env:LLAMA_SERVER_PATH
+if ($envPath) {
+    $SearchPaths = @($envPath) + $SearchPaths
+}
+
+# Also check system PATH
+$systemPath = (Get-Command llama-server -ErrorAction SilentlyContinue)
+if ($systemPath) {
+    $SearchPaths += $systemPath.Source
+}
+
+$FoundBinary = $null
+foreach ($p in $SearchPaths) {
+    if (Test-Path $p) {
+        $FoundBinary = $p
+        break
+    }
+}
+
+if (-not $FoundBinary) {
+    Write-Host "   [FAIL] llama-server.exe not found!" -ForegroundColor Red
+    Write-Host ""
+    Write-Host "   Searched locations:" -ForegroundColor Gray
+    foreach ($p in $SearchPaths) {
+        Write-Host "     - $p" -ForegroundColor Gray
+    }
+    Write-Host ""
+    Write-Host "   To fix: Run setup.bat to build llama.cpp, or set:" -ForegroundColor Yellow
+    Write-Host '   $env:LLAMA_SERVER_PATH = "C:\path\to\llama-server.exe"' -ForegroundColor Yellow
+    exit 1
+}
+
+Write-Host "   [OK] Found: $FoundBinary" -ForegroundColor Green
+
+# -- Step 2: Check file info --------------------------------------------
+Write-Host ""
+Write-Host "2. Binary info..." -ForegroundColor Yellow
+
+$fileInfo = Get-Item $FoundBinary
+$sizeMB = [math]::Round($fileInfo.Length / 1MB, 1)
+Write-Host "   Size:     $sizeMB MB" -ForegroundColor Gray
+Write-Host "   Modified: $($fileInfo.LastWriteTime)" -ForegroundColor Gray
+
+# -- Step 3: Check for CUDA symbols ------------------------------------
+Write-Host ""
+Write-Host "3. Checking for CUDA support..." -ForegroundColor Yellow
+
+# Run with --help or -v and capture output to check for CUDA indicators
+$helpOutput = & $FoundBinary --version 2>&1 | Out-String
+if (-not $helpOutput) {
+    $helpOutput = ""
+}
+
+# Check binary dependencies for CUDA DLLs using dumpbin if available
+$dumpbin = (Get-Command dumpbin -ErrorAction SilentlyContinue)
+$hasCudaDlls = $false
+
+if ($dumpbin) {
+    $deps = & dumpbin /dependents $FoundBinary 2>&1 | Out-String
+    if ($deps -match "cudart|cublas|cublasLt|nvcuda") {
+        $hasCudaDlls = $true
+        Write-Host "   [OK] CUDA DLLs found in dependencies (dumpbin)" -ForegroundColor Green
+        # Extract CUDA DLL names
+        $cudaDlls = ($deps -split "`n") | Where-Object { $_ -match "cuda|cublas|nvcuda" } | ForEach-Object { $_.Trim() }
+        foreach ($dll in $cudaDlls) {
+            if ($dll) { Write-Host "     - $dll" -ForegroundColor Gray }
+        }
+    } else {
+        Write-Host "   [WARN] No CUDA DLLs found in dependencies!" -ForegroundColor Red
+        Write-Host "   This binary was likely compiled WITHOUT -DGGML_CUDA=ON" -ForegroundColor Red
+    }
+} else {
+    # Fallback: check file size (CUDA builds are typically > 50MB)
+    if ($sizeMB -gt 40) {
+        Write-Host "   [LIKELY OK] Binary is $sizeMB MB (CUDA builds are typically > 50MB)" -ForegroundColor Green
+    } else {
+        Write-Host "   [WARN] Binary is only $sizeMB MB (CPU-only builds are typically < 30MB)" -ForegroundColor Yellow
+        Write-Host "   dumpbin not available for detailed check. Install VS Build Tools." -ForegroundColor Gray
+    }
+}
+
+# -- Step 4: Quick startup test -----------------------------------------
+Write-Host ""
+Write-Host "4. Running startup test (will start and immediately stop)..." -ForegroundColor Yellow
+
+# Start llama-server on a random port with no model -- just check it initializes
+$testPort = Get-Random -Minimum 49152 -Maximum 65535
+$proc = $null
+
+try {
+    $proc = Start-Process -FilePath $FoundBinary `
+        -ArgumentList "--port", $testPort, "--host", "127.0.0.1" `
+        -PassThru -NoNewWindow -RedirectStandardError "$env:TEMP\llama_test_stderr.txt" `
+        -RedirectStandardOutput "$env:TEMP\llama_test_stdout.txt"
+
+    # Give it 3 seconds to start
+    Start-Sleep -Seconds 3
+
+    # Check if it crashed
+    if ($proc.HasExited) {
+        $exitCode = $proc.ExitCode
+        $stderr = ""
+        if (Test-Path "$env:TEMP\llama_test_stderr.txt") {
+            $stderr = Get-Content "$env:TEMP\llama_test_stderr.txt" -Raw
+        }
+        $stdout = ""
+        if (Test-Path "$env:TEMP\llama_test_stdout.txt") {
+            $stdout = Get-Content "$env:TEMP\llama_test_stdout.txt" -Raw
+        }
+
+        $allOutput = "$stdout`n$stderr"
+
+        if ($allOutput -match "failed to initialize CUDA") {
+            Write-Host "   [FAIL] CUDA initialization failed!" -ForegroundColor Red
+            Write-Host "   The binary was compiled without CUDA support or CUDA drivers are missing." -ForegroundColor Red
+            Write-Host ""
+            Write-Host "   Rebuild with: cmake -DGGML_CUDA=ON ..." -ForegroundColor Yellow
+        } elseif ($allOutput -match "HTTPS is not supported") {
+            # This is expected when LLAMA_CURL=OFF -- not a real failure
+            Write-Host "   [OK] Binary started (HTTPS warning is expected -- we use local files)" -ForegroundColor Green
+        } else {
+            Write-Host "   [WARN] Process exited with code $exitCode" -ForegroundColor Yellow
+        }
+
+        if ($allOutput.Trim()) {
+            Write-Host ""
+            Write-Host "   --- Output ---" -ForegroundColor Gray
+            $allOutput.Trim().Split("`n") | ForEach-Object { Write-Host "   $_" -ForegroundColor Gray }
+        }
+    } else {
+        Write-Host "   [OK] llama-server started successfully on port $testPort" -ForegroundColor Green
+
+        # Check CUDA detection from startup output
+        Start-Sleep -Seconds 1
+        $stderr = ""
+        if (Test-Path "$env:TEMP\llama_test_stderr.txt") {
+            $stderr = Get-Content "$env:TEMP\llama_test_stderr.txt" -Raw
+        }
+
+        if ($stderr -match "CUDA") {
+            if ($stderr -match "failed to initialize CUDA") {
+                Write-Host "   [FAIL] CUDA init failed at runtime!" -ForegroundColor Red
+            } else {
+                Write-Host "   [OK] CUDA detected at runtime" -ForegroundColor Green
+            }
+        }
+
+        # Kill it
+        Stop-Process -Id $proc.Id -Force -ErrorAction SilentlyContinue
+        Write-Host "   Stopped test server." -ForegroundColor Gray
+    }
+} catch {
+    Write-Host "   [ERROR] Could not start llama-server: $_" -ForegroundColor Red
+} finally {
+    if ($proc -and -not $proc.HasExited) {
+        Stop-Process -Id $proc.Id -Force -ErrorAction SilentlyContinue
+    }
+    Remove-Item "$env:TEMP\llama_test_stderr.txt" -ErrorAction SilentlyContinue
+    Remove-Item "$env:TEMP\llama_test_stdout.txt" -ErrorAction SilentlyContinue
+}
+
+# -- Step 5: Check llama-quantize ---------------------------------------
+Write-Host ""
+Write-Host "5. Checking llama-quantize..." -ForegroundColor Yellow
+
+$quantizePath = Join-Path (Split-Path $FoundBinary) "llama-quantize.exe"
+if (Test-Path $quantizePath) {
+    $qSize = [math]::Round((Get-Item $quantizePath).Length / 1MB, 1)
+    Write-Host "   [OK] Found: $quantizePath ($qSize MB)" -ForegroundColor Green
+} else {
+    Write-Host "   [WARN] llama-quantize.exe not found alongside llama-server" -ForegroundColor Yellow
+    Write-Host "   GGUF export/quantization won't work without it" -ForegroundColor Yellow
+}
+
+# -- Summary ------------------------------------------------------------
+Write-Host ""
+Write-Host "============================================" -ForegroundColor Cyan
+Write-Host "  Summary" -ForegroundColor Cyan
+Write-Host "============================================" -ForegroundColor Cyan
+Write-Host "   Binary:    $FoundBinary" -ForegroundColor Gray
+Write-Host "   Size:      $sizeMB MB" -ForegroundColor Gray
+if ($hasCudaDlls) {
+    Write-Host "   CUDA:      YES (confirmed via DLL deps)" -ForegroundColor Green
+} elseif ($sizeMB -gt 40) {
+    Write-Host "   CUDA:      LIKELY (large binary size)" -ForegroundColor Yellow
+} else {
+    Write-Host "   CUDA:      NO (rebuild with -DGGML_CUDA=ON)" -ForegroundColor Red
+}
+Write-Host ""
+
+if (-not $hasCudaDlls -and $sizeMB -le 40) {
+    Write-Host "To rebuild with CUDA:" -ForegroundColor Yellow
+    Write-Host '  1. Delete the build dir: Remove-Item -Recurse -Force "$env:USERPROFILE\.unsloth\llama.cpp\build"' -ForegroundColor Gray
+    Write-Host '  2. Re-run: .\setup.bat' -ForegroundColor Gray
+    Write-Host ""
+}