How can I automate Sage9 installation?

I’m assembling a bash script to build trellis/bedrock/sage in one go.
I’m struggling automating composer create-project; this is what i have for now:
printf "YES\n $projectTitle\n $url\n Custom theme based on Sage9\n 0.1\n XXX\n\n ${devurl}\n ${themeFolder}\n 3\n no\n yes\n" | composer create-project roots/sage $themeFolder dev-master
it seems to work but i then get
Interactive mode disabled. Skipping parts of post-create-project routine.

What would be the best way forward?
Could I just git clone and run composer install–but then I’m not sure about how to run the post-create-project routine…