Varnish

Varnish Cache is a web accelerator also famous 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 your site's loading speed. One of the important merits of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which allows you to determine how incoming requests should be dealt with.

Memcached

Memcached is a generic memory caching system for boosting the load speed of dynamic database-driven 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 system uses a client'server architecture. The Memcached memory object caching system is employed by some of the most frequently visited websites on the World Wide Web and is supported by popular CMSs like Joomla and WordPress.

Node.js

Node.js is a software system for building scalable network applications. Written in JavaScript, Node.js uses an event-based, asynchronous input/output model that makes it lightweight and effective, excellent for real-time data-rich apps. 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 DBMS. A database engine is the primary software component that a database management system uses to create, retrieve, update and delete data from a database. The latest release of InnoDB offers substantial improvements in efficiency, reliability and usability. InnoDB provides the standard ACID transaction features, along with foreign key support. It is included by default in most binaries distributed by MySQL AB.