Slim Framework - Slim is a PHP micro framework that helps you quickly write simple yet powerful web applications and APIs.
AffiliateWP - A powerful affiliate marketing solution for WordPress.
ExpressJS - Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple
ReferralMagic - Turn your users and customers into referral magnets.
Iron - Extensible web framework for Rust
Echo - Golang HTTP server framework