moby/buildkit ? reverse-engineered prompt

Build me a fast container image build tool like BuildKit that can turn source code into build artifacts efficiently and repeatably.

I want a daemon and a client, where the daemon handles the actual builds and the client can talk to it from the command line. It should support building Dockerfiles, but also be flexible enough to use other build formats, cache steps intelligently, and reuse work when nothing changed. It should be able to export images in a few common ways, like to a registry or local files, and support running on Linux with rootless mode if possible.

Please make it feel practical for real use, with clear docs, a working example, and a simple way to start a build and inspect the result. If you need to check current implementation details or best practices, look them up online first.