Varnish is a reverse caching proxy.

Fastly is a cloud computing services provider. Fastly's cloud platform provides a content delivery network, Internet security services, load balancing, and video & streaming services.

GitHub Pages is a static site hosting service.

Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.

Apache Traffic Server is an open-source caching and proxying server that serves as an HTTP/1.1 and HTTP/2 reverse proxy with caching capabilities, load balancing, request routing, SSL termination, and support for advanced HTTP features.

OpenResty is a web platform based on nginx which can run Lua scripts using its LuaJIT engine.

Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.

ImageKit is a real-time image and video transformation, optimization, and delivery service with built-in digital asset management, powered by a global CDN.

Amazon CloudFront is a fast content delivery network (CDN) service that securely delivers data, videos, applications, and APIs to customers globally with low latency, high transfer speeds.

Amazon Web Services (AWS) is a comprehensive cloud services platform offering compute power, database storage, content delivery and other functionality.

Amazon S3 or Amazon Simple Storage Service is a service offered by Amazon Web Services (AWS) that provides object storage through a web service interface.

Apache is a free and open-source cross-platform web server software.