Envoy is an open-source edge and service proxy, designed for cloud-native applications.
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.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Imperva is a cyber security software and services company for networking, data, and application security.
Priority Hints exposes a mechanism for developers to signal a relative priority for browsers to consider when fetching resources.