This uses a setup based on PostGIS and osm2pgsql. The database is updated in a 10 minute interval.
Special tables based on spatial operations can be created by sql scripts which are executed right after the hourly updates.
Currently a derived table containing campsites for https://opencampingmap.org and one containing playgrounds for https://babykarte.openstreetmap.de/ are updated at this place.
A special feature of these tables is something I call POI in POI which makes POI of other types located inside POI-Polygons a property of the surounding object. E.g. a restaurant located inside a polygon shaped POI tagged tourism=camp_site will add a feature of type restaurant to the outer POI.
Technically this is done using a PotGIS spatial join using a function called ST_Intersects.
https://brewmap.openstreetmap.de is also using this database.