In theory, I could use pulumi to manage something like Google Cloud Run revisions.

But if I'm setting up a CD/release (Azure Devops/Octopus, etc...) job to do this, I'd like it to be able to specify what container to use, vs. always having to commit to a repo.

However, keep in mind that by default stack config values are designed to be declared in yaml files so they can be checked in to your repo. That’s the whole idea behind infrastructure as code and gitops so you can easily revert to the previous state using git operations (such as revert). Of course, there are some cases where it might be unnecessary or even undesirable. In such cases, you can read those values from other sources (env variables, different files or external sources).

IaC to me is just defining the shape of what could be using code.

But yeah, I totally forgot, it'd just be C# (in my case) at that point. I could use the .NET core configuration system too potentially.