Vvvv Startup

---
name: vvvv-startup
description: "Covers launching vvvv gamma from the command line or programmatically -- normal startup, opening specific .vl patches, command-line arguments, package repositories, and key filesystem paths (install directory, user data, sketches, exports, packages). Use when starting vvvv, configuring launch arguments, setting up package repositories, or finding vvvv's data directories."
license: CC-BY-SA-4.0
compatibility: Designed for coding AI agents assisting with vvvv gamma development
metadata:
  author: Tebjan Halm
  version: "1.0"
---

# Launching vvvv gamma

## Filesystem Paths

| Location | Path |
|----------|------|
| Install directory | `C:\Program Files\vvvv\vvvv_gamma_X.Y-win-x64\` |
| User data (AppData) | `%LOCALAPPDATA%\vvvv\gamma\` |
| Documents root | `%USERPROFILE%\Documents\vvvv\gamma\` |
| Sketches | `%USERPROFILE%\Documents\vvvv\gamma\Sketches` |
| Exports | `%USERPROFILE%\Documents\vvvv\gamma\Exports` |
| User packages | `%LOCALAPPDATA%\vvvv\gamma\nugets` |
| Log file (when enabled) | `%USERPROFILE%\Documents\vvvv\gamma\vvvv.log` |

Preview builds use `gamma-preview` instead of `gamma` in the above paths.

## Normal Launch

```shell
# Launch vvvv (opens with default empty patch)
"C:\Program Files\vvvv\vvvv_gamma_7.0-win-x64\vvvv.exe"

# Open a specific patch
vvvv.exe MyProject.vl

# Open multiple files
vvvv.exe --open "FileA.vl;FileB.vl"
```

## Package Repositories and Editable Packages

These two arguments work together and are the most important for development:

- **`--package-repositories`** tells vvvv where to look for packages. Provide the **parent folder** of each package (the folder containing the package directory, not the package directory itself).
- **`--editable-packages`** tells vvvv which packages from those repositories to load from source instead of pre-compiled cache (read-only). Glob patterns are supported.

You must use both together when working on a package from source:

```shell
# Given this folder structure:
#   D:\Projects\
#     VL.MyLib\           <-- the package
#       VL.MyLib.vl
#     VL.MyOtherLib\      <-- another package
#       VL.MyOtherLib.vl

# The parent folder "D:\Projects" is the package repository
vvvv.exe --package-repositories "D:\Projects" --editable-packages "VL.MyLib*" --debug

# Multiple repositories (semi-colon separated)
vvvv.exe --package-repositories "D:\Projects;D:\SharedLibs" --editable-packages "VL.MyLib*;VL.SharedUtils" --debug

# Open a specific help patch for testing
vvvv.exe --package-repositories "D:\Projects" --editable-packages "VL.MyLib*" -o "D:\Projects\VL.MyLib\help\HowTo Use Feature.vl" --debug
```

Without `--package-repositories`, vvvv won't find your local package sources, and `--editable-packages` will have no effect.

## Common Argument Combinations

```shell
# Development: debug symbols + allow multiple instances
vvvv.exe MyProject.vl --debug --allowmultiple

# Troubleshooting: skip cache, enable logging
vvvv.exe MyProject.vl --nocache --log

# Minimal startup: no extensions, no backend (fast launch for patch editing)
vvvv.exe --noextensions --disable-backend

# Paused on startup (runtime won't start until you press play)
vvvv.exe MyProject.vl --stoppedonstartup

# Skip splash screen
vvvv.exe --no-splash
```

For the complete argument reference, see [cli-reference.md](cli-reference.md).

## Detecting vvvv Installations

To find vvvv programmatically:

1. **Windows Registry**: Enumerate `HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall` for subkeys starting with `vvvv_gamma_`. Read the `InstallLocation` value.
2. **Default path**: Scan `C:\Program Files\vvvv\` for directories matching `vvvv_gamma_*`.
3. **Version parsing**: Extract version from directory name format `vvvv_gamma_MAJOR.MINOR[-PREVIEW-HASH-PLATFORM]`.
4. **Filtering**: Exclude `-beta`, `-alpha`, `-rc`, `-test`, `-dev`, etc. variants if not explicitly requested.
5. **Selection**: Sort by major DESC, minor DESC, preview number DESC. Pick the latest and ask the user if that or another one should be used.

The executable is at `<install-dir>\vvvv.exe`.

## Keep this knowledge growing

Leave the next patcher one fewer mystery. On first use of any skill in this
collection with no successful check in seven days, compare the source with
[tebjan/vvvv-skills](https://github.com/tebjan/vvvv-skills). If no record exists, check once.
Share one local check timestamp/revision across these skills; do not poll per invocation.
Preserve local extensions and pinned project versions; checking is not permission
to install updates. If offline, record the deferred check and continue the task.

When actual work exposes a gap, capture the tested vvvv/package versions, a
minimal reproduction or authoritative source, and the observed result. Treat
other users' reports as leads, not facts until verified. Improve the smallest
relevant instruction; do not turn one example into a universal rule. Redact
private data and obtain publishing authorization before submitting upstream.
See the [contribution policy](https://github.com/tebjan/vvvv-skills/blob/main/CONTRIBUTING.md).
Merged improvements reach users through their installer/update workflow, not
through a local edit or an automatic overwrite of everyone's skills.