Handling such a huge amount of markers on a web-based map is not trivial. Therefore, using a hybrid solution that combines spatial indexing, marker clustering, and tile caching is the way to go.
Relevant Skills and Experience
I'm a GIS specialist with 25+ years of experience in software development and 10+ years in GIS development. I'm experienced in handling raster/vector data, spatial indexing, clustering, caching, etc.
I've successfully used many technologies and tools including MapBox, Google Maps, GeoServer, PostGIS, and many more (check my profile).
Proposed Milestones
$1000 USD - First Release
$250 USD - Final Release