I feel like the Docker container used for pulumi/actions is way too large? Why is it over 500MB? I'm gonna see if I can fork that and get it running on Alpine or something...

Be careful here. NPM or Yarn extensions which require compilation will break if you don't have the same target on your final image. Also, the image size is so big because of Node, NPM, and Yarn 🙂

In particular the pulumi SDK itself uses GRPC which has a native component (in the variant used)

Sure but you could use multistage containers to slim this down significantly. I found an alternative that I am trying out before I go down this path...

Another approach you can use is our (new)

action-install-pulumi-cli

then

setup-node

to run this in a non-docker environment

Is there docs on this?

Not yet - I only pushed them an hour ago 🙂