Varnish

Varnish Cache is a web accelerator also called 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 content. Varnish Cache is very, very fast and will boost the speed of your site. One of the major advantages of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to determine how incoming requests should be tackled.

Memcached

Memcached is a general-purpose memory object caching system for boosting the loading speed of dynamic database-powered sites. It is used to reduce 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 distributed memory caching system uses a two-tier architecture. The Memcached memory object caching system is used by some of the most traffic-hungry web sites on the web and is supported by popular web applications like Joomla and WordPress.

Node.js

Node.js is a software system for writing highly scalable network applications. Written in JavaScript, Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and effective, suitable for high-performance content-intensive 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 database management system. A storage engine is the principal software component that a DBMS uses to create, read, modify and delete data from a database. Its latest edition offers substantial improvements in performance, stability and functionality. InnoDB offers the standard ACID-compliant database transaction properties, along with declarative referential integrity support. InnoDB is included as standard in most binaries distributed by MySQL AB.