Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
OneSignal is a customer engagement messaging solution.
PHP is a general-purpose scripting language used for web development.
Priority Hints exposes a mechanism for developers to signal a relative priority for browsers to consider when fetching resources.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.
VK is a Russian online social media and social networking service.