Varnish

Varnish Cache is a web application accelerator also referred to as an HTTP accelerator. You can install it in front of any server that speaks HTTP and configure it to cache the contents. Varnish Cache is really, really fast and will boost your web site's loading speed. One of the main attributes of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to choose how incoming requests should be dealt with.

Memcached

Memcached is a generic memory object caching system for boosting the speed of dynamic database-powered websites. It is used to lower 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 memory object caching system uses a client'server architecture. The Memcached distributed memory caching system is employed by some of the most traffic-intensive websites on the Internet and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a software system for writing highly scalable Internet apps. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and efficient, suitable for high-performance data-intensive applications. Node.js uses Google's V8 JavaScript engine, libUV, and several built-in libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source DBMS. A storage engine is the primary software component that a DBMS uses to create, retrieve, update and delete data from a database. The latest edition of InnoDB offers substantial improvements in efficiency, reliability and functionality. InnoDB provides the standard ACID transaction attributes, along with foreign key support. InnoDB is included by default in most binaries distributed by MySQL AB.