[chriswarbo]

I get the arguments for using containers, but why use Docker? Especially if you're already using Make? Building a container image is pretty simple in Make (or bash, or anything else); you just copy a "config.json" into the output directory, tar it up, and write its sha256 to a "manifest.json" file.

Update: If you want to include other "layers", e.g. if the Z3 project provides its own image, then just put their SHA256 in the manifest.json too.