Varnish

Varnish Cache is a web accelerator also known as a caching HTTP reverse proxy. You can install it in front of any web server that speaks HTTP and configure it to cache the contents. Varnish Cache is very, very fast and will boost your website's speed. One of the key attributes of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to specify how incoming requests should be tackled.

Memcached

Memcached is a general-purpose distributed memory caching system for increasing the speed of dynamic database-powered sites. It is used to decrease the number of times an external data source (such as a DB or API) is read by caching data and objects in RAM. The Memcached distributed memory object caching system uses a client/server architecture. The Memcached memory object caching system is employed by some of the most traffic-hungry websites on the Internet and is supported by popular Content Management Systems like Joomla and WordPress.

Node.js

Node.js is a software platform for building highly scalable network applications. Written in JavaScript, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and efficient, perfect for real-time content-rich network applications. Node.js uses Google's V8 JavaScript engine, libUV, and several built-in libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source DBMS. A storage engine is the primary software component that a database management system uses to create, retrieve, modify and delete data from a database. The latest version of InnoDB offers significant improvements in efficacy, dependability and functionality. InnoDB offers the standard ACID-compliant database transaction properties, as well as referential integrity support. It is included as standard in most binary distributions from MySQL AB.