Dynamic way to apply themes with Kubernetes

Hi All,
We were so far using a Single EC2 Instance for running our openedx instance. We were looking favourably at using Kubernetes for a scalable deployment. As a starting point we are looking at the below two guides, one for local and another for production

The only option at this point of time, it seems is to build the docker images(of cms and lms) after applying the theme and push it to a docker repository and then use the custo images with tutor k8s

Is there any alternate solution l similar to how we do it here(https://github.com/overhangio/indigo) where we can download the theme repository and use render and etc. commands to apply the theme and thene build the images directly on the host machine.

With Regards,
Shashi Kiran G M