About the Reviewers

Jon Ferry has been designing and developing web-based software in a variety of technologies for over 14 years. He has 5 years of experience developing production-level Ruby applications on Heroku's stack. A graduate from the Rochester Institute of Technology, he currently works as a technical lead at Dealer.com.

For more information about Jon and his projects, visit http://jonferry.com or follow him on Twitter at @jonferry.

Mads Ohm Larsen is a full-stack Ruby on Rails developer, gradually shifting to DevOps. He has, in his line of work, deployed and optimized multiple Rails, Sinatra, and Grape apps on Heroku, using multiple Rubies, including JRuby for better performance. His recent switch to DevOps has allowed him even more insight into the world of optimization.

Mwaki Harri Magotswi, raised in Nairobi, Kenya, started tinkering with computer hardware at the age of 16. This interest led him to learn computer science, and later web development, where he discovered Ruby on Rails, a framework he enjoys developing on. Most recently, he was a software engineer for a recommerce firm, Gazelle, before taking a break to continue his studies. Constantly experimenting, he is currently playing with various Ruby-based blogging platforms and JavaScript MVC frameworks when time allows.

In his free time, he enjoys reading, watching TV, playing video games, watching sports, casual bike rides, scenic drives, cars, craft beers, and the occasional 15 minutes of rugby. He is also a casual traveler, food sampler, and amateur mixologist, willing to try most things at least once.

I dedicate my work on this book to my dear late friend Sophie as well as all my family and friends who have helped me get this far.

Peter Robinett is a backend and mobile developer, with a focus on Scala and iOS development. He is a frequent user of the Heroku platform and a fan of its power and extensibility.

He is currently a developer at Lua Technologies. He also works at Bubble Foundry and blogs occasionally at www.bubblefoundry.com.

Kien Nguyen Trung is a software developer who lives in Hanoi, Vietnam. After spending years in high school learning Mathematics and achieving many rewards, he decided to challenge himself in computer science. He started learning programming from 2006 and fell in love with it.

In his free time, he builds some funny things from scratch, such as Pinterest bots to interact with Pinterest API, a Facemash clone using the Facebook avatar with face recognition, and so on. He runs a blog at http://kiennt.com to write about what he learned and his thoughts on software engineering. He spends a lot of time writing code that not only runs but is also clean and clear. His favorite quote is Any fool can write code that a computer can understand. Good programmers write code that humans can understand by Martin Fowler.

Since August 2012, he has been leading backend development at SimplePrints (http://getsimpleprints.com), a fast-growing start-up of 500 start-up companies. He refactors most of the backend source code in SimplePrints applications so that it is more readable and maintainable. Since June 2014, he has been designing architecture for both backend and iOS applications of SimplePrints. His favorite programming language is Python, but he also works on Ruby, JavaScript, and Objective-C.