GitHub Pages is a static site hosting service.

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.

Node.js is an open-source, cross-platform, JavaScript runtime environment that executes JavaScript code outside a web browser.

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

Express is a web application framework for Node.js, released as free and open-source software under the MIT License. It is designed for building web applications and APIs.