I discovered it while looking at raster solutions, and it is pretty great! The raster stack is pretty bonkers. TiTiler uses at least three fundamental layers: GDAL, RasterIO, and rio-tiler. Each contribute a fairly significant improvement (for the use-case) over the underlying one.
There's a lot to like about GDAL+Rasterio, although I've found having all HTTP requests go through GDAL's C API does result in some limitations on concurrency and multithreading. GDAL's configuration being based entirely on env vars also has its downsides: https://github.com/developmentseed/titiler/issues/186
