Unlike more common steps like node, dir, ws, etc., the withRegistry and perhaps other steps in docker-workflow still seem to rely on serializing a FilePath in the program.dat, via some types in docker-commons. This can lead to poor robustness when resuming builds after restart in some cases.

Any such code should be written to keep only String file paths where they are required, constructing the actual FilePath on the fly from some injected content such as a Launcher.

For compatibility reasons, existing FilePath-typed fields must be retained and honored on deserialization.