I'm currently 2/3 of the way through my first postdoc, and starting to look around at, and apply for, my next job. I've noticed that some places require three letters of recommendation, whereas other places simply require two or three references -- i.e. they will call or email the referee if they view that as appropriate or necessary.
Writing an actual recommendation letter -- which typically has to be uploaded by the recommender -- is much more of an "ask".
Is an actual recommendation letter standard at the UK Lecturer or US Assistant Professor level? The pattern I seem to be seeing is that more prestigious places are more likely to require an actual letter; would others confirm that?