Fastly

Fastly operates a global content delivery network (CDN) with a focus on programmability and performance. Unlike traditional CDNs that cache static files, Fastly lets you run custom logic directly at the edge using its Varnish-based configuration language (VCL) or a WebAssembly runtime called Compute@Edge. This means you can route requests, modify headers, handle authentication, or rewrite URLs without a round trip to your origin server. The platform supports instant cache purging, real-time logging, and fine-grained traffic steering through load balancing and shielding. Fastly integrates with major cloud providers, ecommerce platforms, and CI/CD tools. It also offers DDoS protection and a web application firewall (WAF) powered by Signal Sciences, which Fastly acquired. The company was founded in 2011 by Artur Bergman, a former Varnish developer. It powers high-traffic sites like The New York Times, Shopify, and Reddit. Fastly is a paid service with usage-based pricing; there is no free tier, but you can test it with a free trial.