When running a backfill we would potentially like to be able to change some solid behaviour accordingly. I haven't been able to see how we would be able to detect, in a clean way, at runtime that we're running a backfill. I can see that there is dagster_meta data emitted with pipeline and step events that we could potentially use, but it seems a bit private and maybe not to be relied upon in the future. Can anyone advise on the appropriate strategy or some obvious thing I may have missed?

Hi Paul… for backfills scheduled through dagit, we usually use tags to identify backfill jobs

ahh .. so simple. Thanks!

yup! I think the relevant tag key is

dagster/backfill