I've been using a home-grown image proxy server built on top of libvips. It's capable of generating multiple sizes and thumbnails of a single image on the fly to reduce the load time for different screen sizes.
Do you use something like imgix? Are you happy with its pricing?
I'm thinking about open-sourcing the image proxy server behind Storiny (
https://www.producthunt.com/prod...), allowing others to self-host it.