Varnish

Varnish Cache is a web accelerator also known as a caching HTTP reverse proxy. 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 increase the speed of your web site. One of the key merits of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which enables you to choose how incoming requests should be handled.

Memcached

Memcached is a general-purpose memory object 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 memory caching system is employed by some of the most traffic-hungry web sites on the World Wide Web and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a software platform for writing highly scalable Internet apps. Built on Chrome's JavaScript runtime, Node.js uses an event-based, asynchronous input/output model that makes it lightweight and efficient, perfect for high-performance content-rich network apps. Node.js uses Google's V8 JavaScript engine, libUV, and several in-built libraries.

InnoDB

InnoDB is the default storage engine for the MySQL open-source DBMS. A database engine is the underlying software component that a DBMS uses to create, read, update and delete data from a database. The latest edition of InnoDB features substantial improvements in efficiency, dependability and usability. InnoDB provides the standard ACID-compliant database transaction properties, along with declarative referential integrity support. InnoDB is included as standard in most binary distributions from MySQL AB.