Before you start

• Python 3.11 or newer (3.11 is the version Galileo is developed and tested on). Check with python --version; on macOS/Linux the command may be python3. Raspberry Pi OS Bookworm (64-bit) already ships 3.11.
• Git, to download Galileo and to update it later.
• A few hundred MB of free disk space and an internet connection: the first install downloads large scientific packages (numpy, astropy, scipy, PySide6 and others).
• On Debian/Ubuntu/Raspberry Pi OS, install the basics first: sudo apt install git python3 python3-venv python3-pip.

1. Download Galileo Open a terminal (PowerShell on Windows) in the folder where you want Galileo to live and clone the repository.

   $ git clone https://github.com/gordtulloch/Galileo.git
   $ cd Galileo

2. Create a virtual environment This keeps Galileo's packages separate from the rest of your system. Use python3 instead of python on macOS/Linux if needed.

   $ python -m venv .venv

3. Install the dependencies Install into the virtual environment (you do not need to activate it). Allow a few minutes.

   # Windows
   > .venv\Scripts\pip install -r requirements.txt
   
   # macOS / Linux / Raspberry Pi
   $ .venv/bin/pip install -r requirements.txt

   If pip fails building a package, upgrade it first with .venv/bin/python -m pip install --upgrade pip (Windows: .venv\Scripts\python -m pip install --upgrade pip) and re-run the install.
4. Make the launcher executable (macOS / Linux only) Without this you will see "Permission denied" when starting Galileo.

   $ chmod 700 run.sh

5. Start Galileo Run the launch script from the Galileo folder. It finds the .venv automatically. A splash screen shows while the database is created on first launch; there is nothing to configure beforehand.

   # Windows PowerShell
   > .\run.ps1
   
   # macOS / Linux, or Git Bash on Windows
   $ ./run.sh
   
   # Any platform, without the scripts
   $ .venv/bin/python -m galileo.app          # Windows: .venv\Scripts\python -m galileo.app

   If PowerShell blocks run.ps1, run powershell -ExecutionPolicy Bypass -File .\run.ps1 once, or use the python -m galileo.app form.
6. Update later A manual install does not update itself. To get the latest version, pull the changes and refresh the dependencies.

   $ git pull
   $ .venv/bin/pip install -r requirements.txt   # Windows: .venv\Scripts\pip ...

Where your data lives

Settings, equipment profiles and the image library are kept in a single database (galileo.db) in your user folder, not in the Galileo folder, so updating or deleting the folder never touches your data: %APPDATA%\Galileo on Windows, ~/Library/Application Support/Galileo on macOS, ~/.local/share/galileo on Linux.

Troubleshooting

• "PySide6 is required to run Galileo": you are not using the virtual environment's Python. Start with run.ps1/run.sh, or repeat step 3.
• Python is too old: Galileo needs 3.11 or newer. Install a newer Python and recreate .venv (delete the folder and repeat step 2).
• Still stuck? Ask on Discord or open an issue with your OS, Python version and the log file.