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 the HTTP protocol and configure it to cache the contents. Varnish Cache is really, really fast and will make your site load much faster. One of the main strengths of Varnish Cache is the flexibility of its domain-specific language, VCL, which enables you to define how incoming requests should be handled.

Memcached

Memcached is a generic memory caching system for increasing the load speed of dynamic database-powered websites. 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 memory object caching system uses a client/server architecture. The Memcached distributed memory caching system is used by some of the most frequently visited websites on the World Wide Web and is supported by popular Content Management Systems like Joomla and WordPress.

Node.js

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

InnoDB

InnoDB is the default database engine for the MySQL open-source DBMS. A storage engine is the principal software component that a database management system uses to create, retrieve, update and delete data from a database. The latest version of InnoDB offers substantial improvements in performance, reliability and functionality. InnoDB provides the standard ACID transaction properties, along with declarative referential integrity support. It is included as standard in most binary distributions from MySQL AB.