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 HTTP and configure it to cache the contents. Varnish Cache is very, very fast and will improve the loading speed of your site. One of the essential attributes of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to specify how incoming requests should be dealt with.

Memcached

Memcached is a generic memory object caching system for boosting the speed of dynamic database-powered 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 distributed memory object caching system uses a client/server architecture. The Memcached system is employed by some of the most traffic-hungry web sites on the Internet and is supported by popular Content Management Systems like Joomla and WordPress.

Node.js

Node.js is a software platform for writing highly scalable network apps. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and effective, great for real-time data-rich apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of in-built 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 release of InnoDB offers serious improvements in efficacy, stability and usability. InnoDB provides the standard ACID-compliant transaction properties, along with referential integrity support. InnoDB is included as standard in most binaries distributed by MySQL AB.