Install DemoVexa

DemoVexa runs on your own computer and opens in your browser. This page covers what your computer needs, how to get DemoVexa onto it, and how to start and stop it.

#Requirements

You don't need to install FFmpeg; it comes with DemoVexa's packages. The headless Chrome used for rendering downloads by itself the first time you render.

You connect Claude and ElevenLabs in the setup window the first time DemoVexa opens. See First-run setup.

#Install Node.js and Git

The launcher refuses to start without Node.js 20.9 or newer. If it's missing you'll see "Node.js is not installed (need 20.9 or newer)."

#macOS

brew install node
xcode-select --install

The second command installs Git with Apple's command line tools.

#Windows

Run these in PowerShell:

winget install OpenJS.NodeJS.LTS
winget install Git.Git

#Linux

Install Node.js with nvm, and Git with apt:

nvm install 22
sudo apt install git

To check the version you have, run node --version in a terminal.

#Get DemoVexa

1. Go to the Download page and download DemoVexa for your system.
2. Unzip the download.
3. Move the DemoVexa folder somewhere permanent, such as your home folder.

DemoVexa keeps its data, including your projects and rendered videos, inside this folder by default. Don't leave it in a temporary folder you might clear out.

#Start DemoVexa

Each system has its own launcher in the DemoVexa folder.

Keep the launcher window open while you use DemoVexa.

#What happens when it starts

The launcher:

1. Checks that Node.js 20.9 or newer is installed.
2. Stops a studio left over from an earlier run if it isn't answering.
3. Installs the packages DemoVexa needs, if they're missing.
4. Prepares the local database.
5. Rebuilds the app, but only if its code changed since the last start.
6. Opens your browser at http://localhost:1557 as soon as the studio answers.

The first start takes longest because it installs packages. After that, starts are quick; when a rebuild is needed it takes about 30 seconds on macOS and Linux and about a minute on Windows.

If DemoVexa is already running, the launcher says "The studio is already running" and opens it in your browser instead of starting a second copy.

#Stop and restart

Close the launcher window to stop the web app. Builds, renders and batches that are already running keep going in the background.

To stop or restart from a terminal, run the launcher with a flag from inside the DemoVexa folder:

When it stops, you'll see "Stopped. Builds, renders and batches that were running keep going."

#Linux extras

Linux needs two things the other systems already have:

• Chrome's system libraries (such as libnss3 and libcups2) for rendering. Without them, renders fail with "error while loading shared libraries". Settings → Rendering lists what's missing and gives a command you can copy.
• zenity or kdialog for the Choose folder… button. Without one, you can still paste the full path of a folder.

sudo apt install zenity

#Next

• First-run setup
• Make your first video
• Troubleshooting