Varnish

Varnish Cache is a web accelerator also called as an HTTP accelerator. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the contents. Varnish Cache is very, very fast and will speed up your site. One of the main attributes of Varnish Cache is the flexibility of its domain-specific language, VCL, which enables you to determine how incoming requests should be tackled.

Memcached

Memcached is a generic memory object caching system for increasing the loading speed of dynamic database-powered web sites. 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 caching system uses a client/server architecture. The Memcached memory caching system is used by some of the most traffic-intensive web sites on the World Wide Web and is supported by famous web apps like Joomla and WordPress.

Node.js

Node.js is a software system for building scalable network apps. Written in JavaScript, Node.js uses an event-based, non-blocking input/output model that makes it lightweight and effective, great for high-performance data-intensive network 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 RDBMS. A database engine is the principal software component that a DBMS uses to create, read, update and delete data from a database. The latest release of InnoDB offers considerable improvements in performance, dependability and usability. InnoDB provides the standard ACID database transaction properties, along with foreign key support. InnoDB is included by default in most binary distributions from MySQL AB.