Ganymed is a framework for php-based webapps. The core components are in the ganymed-components repository. It is not maintained at the moment and should not be used in production environments.
To get started you need to have composer.
First clone this repositry to a destination of your choice and invoke composer install in the root folder of your cloned project.
After that you need to create a .env.php config file in the project root. A working example is stored as .env.example.com. You can just rename this file.
Navigate to the public folder in your project root and run php -S localhost:8000 to test it. If You visit localhost:8000 You should see a page with the ganymed headline.