Cowboy is a small, fast, modular HTTP server written in Erlang.
Express is a web application framework for Node.js, released as free and open-source software under the MIT License. It is designed for building web applications and APIs.
Google Publisher Tag (GPT) is an ad tagging library for Google Ad Manager which is used to dynamically build ad requests.
Heroku is a cloud platform as a service (PaaS) supporting several programming languages.