Windows Platform Guide¶

Windows is Pulp's second supported platform. This guide covers building, audio/MIDI setup, signing, and deployment.

Requirements¶

Windows 10 version 1903+ (x64 or ARM64)
Visual Studio 2022 (17.x) with C++ desktop workload
Git for Windows (the supported wrapper uses its bundled Git Bash)
CMake 3.24+
C++20 compiler (MSVC v143+)

First-Time Bootstrap¶

Use the PowerShell wrapper, not raw ./setup.sh, as the supported Windows entrypoint:

powershell -ExecutionPolicy Bypass -File .\setup.ps1

setup.ps1 imports the Visual Studio C++ environment, resolves Git Bash from Git for Windows, and temporarily maps the checkout to a short drive alias so nested dependency bootstrap does not trip Windows path-length limits.

External SDKs¶

# Bootstrap pinned shared dependencies and SDKs
powershell -ExecutionPolicy Bypass -File .\setup.ps1 --deps-only

# VST3 SDK (MIT) is then provided under external/vst3sdk from Pulp's shared SDK cache.
# CLAP (MIT) is fetched automatically via CMake FetchContent.
# AudioUnit SDK is not used on Windows.

Building¶

Command Line (Developer PowerShell / Developer Command Prompt)¶

powershell -ExecutionPolicy Bypass -File .\setup.ps1 --deps-only
cmake -S . -B C:\pulp-build -G "Visual Studio 17 2022" -A x64
cmake --build C:\pulp-build --config Release
ctest --test-dir C:\pulp-build --output-on-failure -C Release

On Windows on ARM, use -A ARM64 instead. If you have both Visual Studio Community and Build Tools installed, you can force the full IDE instance with -DCMAKE_GENERATOR_INSTANCE="C:/Program Files/Microsoft Visual Studio/2022/Community". If you bypass setup.ps1, keep your checkout/build paths short. Nested FetchContent paths under _deps/ can otherwise exceed the classic 260-character limit during MSBuild configure steps.

Visual Studio IDE¶

cmake -S . -B build -G "Visual Studio 17 2022" -A x64
# Open build/pulp.sln in Visual Studio

Ninja (faster builds)¶

cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
cmake --build build

Audio I/O (WASAPI)¶

Pulp uses WASAPI (Windows Audio Session API) for low-latency audio on Windows. The implementation uses shared mode with event-driven buffering.

How It Works¶

Shared mode: audio is mixed with other applications (no exclusive device lock)
Event-driven: a background thread waits on buffer events, minimizing latency
Float32 non-interleaved: Pulp's callback receives per-channel buffers; interleaving to/from WASAPI's format is handled internally
Thread priority: the render thread runs at THREAD_PRIORITY_TIME_CRITICAL

Device Enumeration¶

auto system = pulp::audio::create_audio_system();
auto devices = system->enumerate_devices();
for (const auto& dev : devices) {
    // dev.name, dev.id, dev.max_output_channels, dev.sample_rates
}

Standalone Apps¶

The standalone host (pulp::format::StandaloneHost) automatically uses WASAPI on Windows. No additional configuration needed — it uses the default output device at the system's native sample rate.

MIDI I/O (Win32 MIDI)¶

Pulp uses the Win32 MIDI API (midiIn*/midiOut*) for MIDI on Windows.

Device Enumeration¶

auto system = pulp::midi::create_midi_system();
auto inputs = system->enumerate_inputs();
auto outputs = system->enumerate_outputs();

Callback-Based Input¶

MIDI input uses the Win32 CALLBACK_FUNCTION mechanism. Messages are dispatched to Pulp's MidiInputCallback with status byte, data bytes, and millisecond timestamps.

GPU Rendering (D3D12)¶

Dawn (Pulp's WebGPU implementation) supports D3D12 natively on Windows. When GPU rendering is enabled (PULP_ENABLE_GPU=ON), the Skia Graphite backend renders via D3D12 through Dawn.

No additional setup is needed — Dawn selects the D3D12 backend automatically on Windows. On Windows on ARM, the pinned WebGPU dependency also has an aarch64 prebuilt runtime, so normal GPU-enabled smoke validation can stay on the standard dependency path.

Plugin Formats¶

VST3¶

VST3 plugins are built as .vst3 bundles. Default install locations:

System-wide: C:\Program Files\Common Files\VST3\
Per-user: %LOCALAPPDATA%\Programs\Common\VST3\

CLAP¶

CLAP plugins are built as .clap files. Default install locations:

System-wide: C:\Program Files\Common Files\CLAP\
Per-user: %LOCALAPPDATA%\Programs\Common\CLAP\

No AU on Windows¶

Audio Units are macOS/iOS only. Windows builds produce VST3 and CLAP formats.

Code Signing (Authenticode)¶

Using signtool¶

Windows code signing uses signtool.exe from the Windows SDK:

# Sign with a certificate by name
signtool sign /n "Your Publisher Name" /t http://timestamp.digicert.com /fd sha256 MyPlugin.vst3

# Verify signing
signtool verify /pa MyPlugin.vst3

Azure Trusted Signing¶

For cloud-based EV certificates (no hardware token required):

# Install Azure SignTool
dotnet tool install --global AzureSignTool

# Sign with Azure Trusted Signing
AzureSignTool sign -kvu "https://your-vault.vault.azure.net" \
  -kvc "your-cert-name" \
  -tr http://timestamp.digicert.com -td sha256 \
  MyPlugin.vst3

Via Pulp CLI¶

pulp ship sign --identity "Your Publisher Name"
pulp ship check  # verify signing status

Windows Installer (NSIS)¶

Pulp can generate NSIS installers for distributing plugins on Windows.

Requirements¶

Install NSIS: https://nsis.sourceforge.io/ — makensis must be on PATH.

Creating an Installer¶

pulp ship package --version 1.0.0

The installer: - Installs VST3 to %COMMONFILES%\VST3\ - Installs CLAP to %COMMONFILES%\CLAP\ - Creates Start Menu shortcuts and uninstaller - Registers with Windows Add/Remove Programs

Per-User Installation¶

For installs that don't require administrator privileges:

pulp ship package --version 1.0.0 --per-user

This installs to %LOCALAPPDATA%\Programs\Common\ instead of %COMMONFILES%\.

CI/CD (GitHub Actions)¶

The build workflow includes a Windows matrix entry:

- os: windows-latest
  name: Windows (x64)

Windows CI: - Clones VST3 SDK - Configures with CMake (MSVC) - Builds in Release mode - Runs cross-platform unit tests - Uploads VST3 and CLAP artifacts

Troubleshooting¶

WASAPI: "could not activate audio client"¶

The audio device may be in use exclusively by another application, or the device may have been removed. Check Windows Sound settings to verify the default output device is available.

MIDI devices not appearing¶

Ensure MIDI devices are connected before enumerating. The Win32 MIDI API does not support hot-plugging — restart the application after connecting new MIDI hardware.

Build fails with MSVC errors¶

Ensure you're using Visual Studio 2022 (v143 toolset). Older MSVC versions may not fully support C++20 features used by Pulp.

Plugin not found by DAW¶

Verify the plugin is installed to the correct system directory. Most DAWs scan C:\Program Files\Common Files\VST3\ — check your DAW's plugin scan path settings.