dinker VS buildah

(Self plug) I had the same thoughts as the author, and made this: https://github.com/andrewbaxter/dinker . Like stated in the article, if you're doing rust or go all you want is to dump the binary in the image. There's no reason to do the build inside the docker vm in that case, and it's super fast, and only uses dumb filesystem access - no daemons like docker, weird wip container managers like buildah, etc.

Self hoisting here, I put this together to make it easier to generate single (extra) layer docker images without needing a docker agent, capabilities, chroot, etc: https://github.com/andrewbaxter/dinker

Caveat: it doesn't work on Fly.io. They seem to be having some issue with OCI manifests: https://github.com/containers/skopeo/issues/1881 . They're also having issues with new docker versions pushing from CI: https://community.fly.io/t/deploying-to-fly-via-github-actio... ... the timing of this post seems weird.

FWIW the article says

> create a Docker image, also known as an OCI image

I don't think this is quite right. From my investigation, Docker and OCI images are basically content addressed trees, starting with a root manifest that points to other files and their hashes (root -> images -> layers -> layer configs + files). The OCI manifests and configs are separate to Docker manifests and configs and basically Docker will support both side by side.

For the task of building the graph image, my first idea was to rely on buildah. In fact, our design was already heavily relying on containers/image for all things regarding copying images from one registry to the other, or from one registry to an archive. The obvious choice was to use the same suite of modules in order to keep dependencies to a minimum.

I appreciate that podman can run daemonless, but I've gotten tired of waiting for them to implement heredoc support and have continued to use docker.

You do realize that, under the hood, buildah uses a container engine (runc by default)? See https://github.com/containers/buildah/blob/main/docs/buildah...

buildah

I found this small tutorial: https://github.com/containers/buildah/blob/main/docs/tutorials/04-include-in-your-build-tool.md and it works.

# https://github.com/containers/buildah/issues/3666 volume /var/lib/containers

Last week, Buildah version 1.29 was also released. The prune command has been added to clean intermediate images as well as the build and mount cache.  Support for the –group-add option to the from and build commands was added. One useful feature of this, it to use the –group-add keep-groups option, which allows rootless users to take advantage of their group access to file and devices mounted into the build containers. And the –cache-from and –cache-to options for the build command now allow for multiple sources. This can be used to improve the speed of builds, especially in CI/CD environments.

Unfortunately this syntax is not generally supported yet - it's only supported with the buildkit backend and only landed in the 1.3 "labs" release. It was moved to stable in early 2022 (see https://github.com/moby/buildkit/issues/2574), so that seems to be better, but I think may still require a syntax directive to enable.

Many other dockerfile build tools still don't support it, e.g. buildah (see https://github.com/containers/buildah/issues/3474)

Useful now if you have control over the environment your images are being built in, but I'm excited to the future where it's commonplace!

For more information regarding the bundled tools see: CRI tools.