Foreword

From the time Badr Bellaj first told me about his intention to write a book about blockchain, I was highly supportive of his endeavor. I even managed to suggest topics that I, as a veteran developer, still needed to understand. A year later, after reading this book, my expectations have been surpassed and I could not be happier. Therefore, it's my pleasure to provide this foreword and to recommend Bellaj's book, Blockchain by Example.

It is generally agreed that blockchain is a disruptive technology that has shaken the IT scene. Consequently, it has increasingly drawn the interest of a lot of developers. However, according to my experience, it's hard for newcomers to find a helpful guide that explains blockchain in the easiest possible terms, and teaches with concrete examples how to use major blockchain solutions to build projects.

This book is intended to change this situation and acts as an introduction to blockchain technology from a developer viewpoint. It's an undertaking of great potential value, and Bellaj and his coauthors have done it justice.

In fact, this book will help you, step by step, to build realistic projects from scratch using different concepts and technologies, namely Bitcoin, Ethereum, Quorum, and Hyperledger. You'll find, among other topics, how a developer can create a Bitcoin-like coin, run an ICO, and implement privacy-preserving solution in business.

This book isn't just for absolute beginners. It's also a good book for introducing experienced programmers to blockchain technologies or even bringing up to speed developers already familiar with these technologies. It helps if you know a bit about blockchain when you step in, but if you don't, hang on and you should pick up the basic ideas as you go along.

Bellaj is an educator, and a darn good one. He wants us to acquire practical skills instead understanding only the superficial concepts! He knows that if you and I are ready to learn, we have to practice: we have to do the work. In his chapters, he will continually challenge you to propose new features for the presented project. We are well advised to try to implement what he suggests and to create pull requests.

I have enjoyed the book and found it valuable. I think you will, too. Enjoy!

Sam Hauer

Cofounder of NSApps