Stefan Birkner has a passion for software development. He has a strong preference for beautiful code, tests, and deployment automation. Stefan is a contributor to JUnit and maintains a few other libraries.

Jose Muanis Castro holds a degree in information systems. Originally from the sunny Rio de Janeiro, he now lives in Brooklyn with his wife and kids. At The New York Times, he works with recommendation systems on the personalization team. Previously, he worked on CMS and publishing platforms at Globo.com in Brazil.

Jose is a seasoned engineer with hands-on experience in several languages. He's passionate about continuous improvement, agile methods, and lean processes. With a lot of experience in automation, from testing to deploying, he constantly switches hats between development and operations. When he's not coding, he enjoys riding around on his bike. He was a reviewer on the 2014 book, Mastering Unit Testing Using Mockito and JUnit, Packt Publishing. His Twitter handle is @muanis.

John Piasetzki has over 15 years of professional experience as a software developer. He started out doing programming jobs when he was young and obtained a bachelor of science degree in computer engineering. John was fortunate enough to get his start in programming by contributing to WordPress. He continued by working at IBM on WebSphere while getting his degree. Since then, he has moved on to smaller projects. John has worked with technologies such as Python, Ruby, and most recently, AngularJS. He's currently working as a software developer at OANDA, a foreign exchange company.