Lee Zhi Eng is a 3D artist-turned-programmer who worked as a game artist and game programmer in several local game studios in his country before becoming a contractor and a part-time lecturer at a local university, teaching game development subjects, particularly related to Unity Engine and Unreal Engine 4. You can find more information about him at http://www.zhieng.com.

Andrea Flesca is an Italian electronic engineer working in the software world for Selex ES, a primary Italian electronic systems and software provider, which has now become the IT division of Finmeccanica.

He has more than 15 years of software development experience, supporting the complete software life cycle management: requirement analysis and management, system architecture and design, C++/Java implementation, documentation and tests and validation. Also, his work focuses on technical solutions, design patterns, middleware, team leadership and mentoring, and customer relationships.

He has gained experience in GIS solutions through open source and ESRI technology, GIS analysis and development, web applications, cross-platform development, distributed computing systems, JEE and SOA architectures, enterprise service bus, and enterprise architecture integration.

He has worked for bank systems, telecommunications, and defense and currently works for smart cities and systems as an integration engineer.

From 2014, Andrea has been collaborating with Packt Publishing as a technical reviewer.

He loves rock music and prepares a great tiramisu. He can be contacted on LinkedIn.

Niels Holst graduated from the University of Copenhagen, Denmark, with a PhD in Biology and a BSc in Computer Science. He currently works at Aarhus University, Denmark, where he applies computer science to solve problems in Applied Ecology. He is a leader of the Universal Simulator open source project.

Sudhendu Kumar has been a GNU/Linux user for more than 6 years. Presently, he is a software developer for a networking giant. In his free time, he contributes to KDE.