The success of an API is measured by how fast and easy developers can integrate with that. In the micro-services environment, where each service has a well-defined responsibility, it's not enough to have a well designed API, it's necessary to establish a contract between the APIs, so the integration between them may be feasible. In this talk, I will go through a set of best practices that will help to design APIs and define a communication service contract. From skateboarder to runner, photographer to full stack developer, Alberto loves writing beautiful code at Globo.com, Brazil, the internet branch of the largest mass media group in South America. He works in an environment of micro services, with lots of Ruby, Rails, Python, Tornado Web Server, Nginx, Javascript and Java.