Best way to fetch and cache markers on pan zoom

[Ladvace]

What is the best way to efficiently fetch and catch (many) markers that also need to be clustered so they do not flicker?
I currently have a custom backend that I call to get markers, given bounds coordinates. The problem is that whenever you pan zoom since they get refetched, they "flicker." I would need a way to cache them but free the cache when there are too many markers. I also cluster the markers.