Varnish

Varnish Cache is a web application 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 make your web site load much faster. One of the key virtues of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to determine how incoming requests should be tackled.

Memcached

Memcached is a general-purpose distributed memory caching system for boosting the speed of dynamic database-driven sites. It is used to lower the number of times an external data source (such as a database or API) is read by caching data and objects in RAM. The Memcached system uses a client'server architecture. The Memcached distributed memory caching system is used by some of the most traffic-hungry web sites on the Internet and is supported by popular web applications like Joomla and WordPress.

Node.js

Node.js is a software platform for building scalable Internet apps. Written in JavaScript, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and effective, suitable for real-time data-rich applications. Node.js uses Google's V8 JavaScript engine, libUV, and a number of built-in libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source relational database management system. A database engine is the underlying software component that a database management system uses to create, retrieve, update and delete data from a database. Its latest version features substantial improvements in efficacy, security and usability. InnoDB offers the standard ACID database transaction attributes, along with foreign key support. It is included as standard in most binary distributions from MySQL AB.