All images in Altostra are saved in a bucket owned by the customer - that is the image repository. Altostra does not directly store your projects, source code or build artifacts.
The first cloud services account you connect in Altostra, will be the default account and will host your image repository.
Every time you use the push command, a new image is created and uploaded to the image repository. When you deploy a project, the image name you provide during the deployment is used to fetch that image from the repository and deploy it to your account.