There are various ways to approach this. One is setting up a standard tile server for OSM tiles (see e.g. switch2osm.org) [switch2osm.org)](http://switch2osm.org) and then use a different infrastructure to render you your POIs onto transparent tiles; in the browser, display both the base tile and the overlay tile. Advantage: Overlay can be switched off; no changes required to standard rendering toolchain; any toolchain can be used for your tiles (e.g. UMN Map Server or even a commercial product). Another approach is setting up a standard tile server and modifying its rendering style to display your POIs. That would yield only one tile with both OSM any your POI on it. A third way is to have a database backend that only sends to the browser that portion of your 45,000 POIs that are required for the current viewport. See www.wheelmap.org for an example of such technology. Advantage: individual POIs are still present as geometries in the browser and hence clickable. There are even more possible solutions but listing them all is not possible here.

There are various ways to approach this. One is setting up a standard tile server for OSM tiles (see e.g. switch2osm.org) and then use a different infrastructure to render you POIs onto transparent tiles; in the browser, display both the base tile and the overlay tile. Advantage: Overlay can be switched off; no changes required to standard rendering toolchain; any toolchain can be used for your tiles (e.g. UMN Map Server or even a commercial product). Another approach is setting up a standard tile server and modifying its rendering style to display your POIs. That would yield only one tile with both OSM any your POI on it. A third way is to have a database backend that only sends to the browser that portion of your 45,000 POIs that are required for the current viewport. See www.wheelmap.org for an example of such technology. Advantage: individual POIs are still present as geometries in the browser and hence clickable. There are even more possible solutions but listing them all is not possible here.