buildkit-pack

Dependcies are also for multiple stages, e.g.: So `COPY --from=<some stage>` and `FROM <other stage>` Also, a Dockerfile is just a frontend for buildkit. The heart of buildkit is "LLB" (sort of like LLVM IR in usage) which is what the Dockerfile compiles into. Buildkit just executes LLB, doesn't have to be from a Dockerfile. For that matter you can have a "Dockerfile" (in name only) that is not even really dockerfile since the format lets you specify frontend to use (which would be a container image reference) to process it. There's even a buildkit frontend to build buildpacks: https://github.com/tonistiigi/buildkit-pack Works with any buildkit enabled builder, even `docker build`.

Link to the buildpack frontend for docker: https://github.com/tonistiigi/buildkit-pack

I would say check out buildkit, which is the tech behind "docker build"'s new builder. I don't know if the Dockerfile format is really suitable for this, but you can now build your own format and Docker can just build it. Basically buldkit breaks things down into a frontend format (like Dockerfile) and a frontend parser which gets specified as an image at the top of your file (`#syntax=<some image>`), the parser converts the frontend format into an intermediary language (called llb), buildkit takes the llb and passes it to a backend worker. This all happens behind the scenes with `DOCKER_BUILDKIT=1 docker build -t myImage .` Docker actually ships new Dockerfile features that aren't tied to a docker version this way. Actually there are a number of new Dockerfile features that might get you what you need, even if the format isn't all that g