Am stuck with this. This must be implemented, as it is a very very very basic feature and would rid so many headaches.
What all the “workarounds” do not account for is the fact, that in a pipeline, where each step should only require the tools actually needed to accomplish this single step, you cannot “just” pull and push an image, as only build steps require a Docker agent and all other steps have their own jobs.
So, for the pull/push workaround to work, I would need to dirty the other job stages with an entire Docker engine, just so fly.io can fly around the issue in a clumsy manner.
Please, fix!