I looked into switching to zstd recently however at least crane the utility that rules_oci uses to upload containers does not yet support uploading zstd layers.

https://github.com/google/go-containerregistry/pull/1827

Issue is over two years old. Man it is so sad how hard it can be to upstream work to big open source projects. I have a number of PRs open on both the kubernetes and etcd projects and it is almost impossible to get anyone to review them, and since nobody will review my PRs I cannot get enough work under my belt to be a committer. Sometimes I feel like if you don’t have an @redhat or @google account people just ignore you.