Varnish

Varnish Cache is a web accelerator also known 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 increase the loading speed of your web site. One of the important attributes of Varnish Cache is the flexibility of its domain-specific language, VCL, which permits you to determine 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 caching system uses a two-tier architecture. The Memcached memory object caching system is used by some of the most traffic-intensive web sites on the Internet and is supported by popular CMSs like Joomla and WordPress.

Node.js

Node.js is a platform for building scalable network apps. Written in JavaScript, Node.js uses an event-based, non-blocking I/O model that makes it lightweight and effective, perfect for high-performance data-rich network 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 relational database management system. A database engine is the main software component that a DBMS uses to create, retrieve, modify and delete data from a database. The latest version of InnoDB features serious improvements in performance, reliability and usability. InnoDB provides the standard ACID-compliant transaction properties, along with referential integrity support. InnoDB is included as standard in most binary distributions from MySQL AB.