Cannot run HOST commands before FROM/INPLACE

[aniongithub]

However, this may be needed if we're creating the image from scratch or copying/modifying files from a raw rootfs or any other unforeseen scenario.

In any case, disallowing HOST before FROM/TO or INPLACE is unnecessary as they can always run regardless of chroot setup.

[oxzi]

Thanks a lot for your request.

Based on pimod's stage based architecture, the setup stage's commands (FROM, TO, INPLACE) are always executed before those commands of the chroot stage (like HOST).
I just realized this isn't really documented in the README file, but more in the linked paper in section IV. Implementation. I am going to update the README to create a better understanding of pimod's internals and how those are affecting its usage.

However, back to your request, is there a real need for such a pre-stage, being executed before something else? Maybe this might be even out of pimod's scope? Please feel free to express your opinion.