Varnish

Varnish Cache is a web application accelerator also popular as a caching HTTP reverse proxy. You can install it in front of any web server that speaks the HTTP protocol and configure it to cache the contents. Varnish Cache is very, very fast and will boost your site's speed. One of the chief strengths of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to choose how incoming requests should be tackled.

Memcached

Memcached is a general-purpose memory object caching system for increasing the load speed of dynamic database-driven web sites. It is used to decrease 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 distributed memory caching system uses a client'server architecture. The Memcached distributed memory caching system is used by some of the most traffic-heavy sites on the web and is supported by famous web applications like Joomla and WordPress.

Node.js

Node.js is a software platform for writing scalable Internet applications. Written in JavaScript, Node.js uses an event-driven, non-blocking input/output model that makes it lightweight and effective, perfect for real-time content-intensive network 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 database engine is the principal software component that a database management system uses to create, retrieve, update and delete data from a database. The latest edition of InnoDB offers significant improvements in performance, reliability and functionality. InnoDB provides the standard ACID transaction properties, along with declarative referential integrity support. It is included by default in most binary distributions from MySQL AB.