I’ve released a new version which breaks the storage down by-layer. This means that it’s possible to only regenerate the layers that have changed. For example, if you add a new building it won’t have to regenerate the roads layer.
This has brought the update speed up to minutely, taking seconds to consume a minute’s update.
I’ll set up automatic jobs to handle the coastlines and low zooms, then get back to issues reported in the tiles. With updates so much faster, it’s easier to develop. Thanks for @SomeoneElse doing a lot of good testing.