Varnish

Varnish Cache is a web accelerator also popular as an HTTP accelerator. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the content. Varnish Cache is very, very fast and will speed up your web site. One of the main features of Varnish Cache is the flexibility of its domain-specific language, VCL, which allows you to specify how incoming requests should be dealt with.

Memcached

Memcached is a general-purpose memory caching system for increasing the speed of dynamic database-driven 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 object caching system uses a two-tier architecture. The Memcached memory caching system is employed by some of the most traffic-heavy web sites on the World Wide Web and is supported by famous web applications like Joomla and WordPress.

Node.js

Node.js is a software system for writing scalable Internet applications. Written in JavaScript, Node.js uses an event-driven, asynchronous I/O model that makes it lightweight and efficient, excellent for real-time content-rich apps. Node.js uses Google's V8 JavaScript engine, libUV, and several built-in libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source relational database management system. A database engine is the main software component that a DBMS uses to create, retrieve, update and delete data from a database. The latest version of InnoDB offers considerable improvements in performance, reliability and functionality. InnoDB offers the standard ACID transaction features, as well as declarative referential integrity support. InnoDB is included as standard in most binaries distributed by MySQL AB.