I've had a good experience with Podman as a Docker alternative. The Podman CLI is designed to be API-compatible with Docker's CLI, so most things should just work. The only thing I've had to change with my Dockerfiles (or Containerfiles) is the `SHELL` instruction, since Podman by default builds OCI images, and that instruction is not supported by the OCI standard. But you can still specify the shell individually for the `RUN` instructions, or even just use `--format=docker` if you don't want OCI images.