Varnish

Varnish Cache is a web application accelerator also referred to 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 improve the speed of your web site. One of the major virtues of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to determine how incoming requests should be dealt with.

Memcached

Memcached is a general-purpose memory object caching system for speeding up dynamic database-powered web sites. It is used to reduce 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 caching system uses a client'server architecture. The Memcached distributed memory caching system is employed by some of the most traffic-intensive web sites on the World Wide Web and is supported by popular CMSs like Joomla and WordPress.

Node.js

Node.js is a platform for building scalable Internet apps. Written in JavaScript, Node.js uses an event-driven, asynchronous I/O model that makes it lightweight and effective, excellent for real-time content-heavy Internet apps. Node.js uses Google's V8 JavaScript engine, libUV, and several in-built libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source DBMS. A storage engine is the main software component that a database management system uses to create, retrieve, update and delete data from a database. Its latest edition offers substantial improvements in efficiency, security and functionality. InnoDB offers the standard ACID-compliant database transaction features, as well as declarative referential integrity support. InnoDB is included as standard in most binaries distributed by MySQL AB.