Varnish

Varnish Cache is a web application accelerator also referred to 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 boost the speed of your site. One of the major attributes of Varnish Cache is the flexibility of its principal configuration mechanism, VCL, which permits you to determine how incoming requests should be dealt with.

Memcached

Memcached is a generic memory caching system for boosting the speed of dynamic database-powered sites. It is used to decrease 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 object caching system uses a client/server architecture. The Memcached memory caching system is used by some of the most popular web sites on the Internet and is supported by famous CMSs like Joomla and WordPress.

Node.js

Node.js is a platform for building highly scalable Internet applications. Written in JavaScript, Node.js uses an event-based, asynchronous I/O model that makes it lightweight and efficient, suitable for high-performance data-rich Internet 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 relational database management system. A storage engine is the principal software component that a database management system uses to create, read, update and delete data from a database. Its latest version features considerable improvements in performance, security and usability. InnoDB provides the standard ACID-compliant database transaction attributes, as well as referential integrity support. It is included as standard in most binaries distributed by MySQL AB.