Chris McCord - Metaprogramming Elixir: Write Less Code, Get More Done (and Have Fun!)

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To my lovely wife, Jaclyn.

This book wouldnt have been possible without the help of a number of people whose hard work and support cant go without mention. These names deserve recognition for making the book what it is today.

Metaprogramming Elixir clearly wouldnt have been possible without all the hard work that Jos dedicated to crafting this wonderful language. Beyond that, though, he has been a true community leader and a helpful friend. His welcoming and kind nature has shaped Elixirs community and set a precedent for how an OSS project should be run. He has been constant source of help and inspiration along the way.

As my boss at my full-time job, Matt gave me the flexibility to make this book possible. From a work atmosphere that fosters personal growth, to his support for community outreach, he helped make this book a reality. For that, Im truly thankful.

Working closely with Jackie on this book has been a great pleasure. Jackies guiding feedback and encouragement led to a work that Im extremely proud of. This book would not have been the same without her.

It has been an honor to work with the Pragmatic Programmers. Dave Thomas and Andy Hunt welcomed me into the Prag family, and their close-knit operation made me feel right at home. Susannah Pfalzer offered wisdom and encouragement while pushing me to do my best. Im extremely grateful for the entire Prag team and the level of care I received throughout this journey.

The reviewers have my gratitude for dedicating their time and knowledge to help make this book the best it could be. Jos Valim, Bruce Tate, Jason Stiebs, Matt Sears, Zander Hill, Ryan Cromwell, and Gabriel Jaldon all took time out of their busy lives to offer guidance and support. Jason Stiebs deserves particular credit for being available at all hours of the day and night to offer feedback throughout the process.

In 2012, Jos Valim announced that he was working on his own programming language. At the time, I thought he was crazy. Little did I know the impact his creation would have on the way I view programming. Since discovering it, I cant bear to put down the keyboard. The amount of care that went into the languages design and the level of power it gives you is truly freeing. Its the only language Ive found that makes it a joy to build scalable, fault-tolerant systems. Combined with all the innovations from the Erlang ecosystem, its a language you can easily fall in love with. Throughout this book, youll find out why.

Were going to explore metaprogramming in Elixir from the ground up. Along the way, youll level up your programming skills and discover the full potential of Elixirs macro system. After youre finished, youll know the ins and outs of Elixir at a fundamental level, and youll be able to write incredible libraries that let you do more with less code.

Metaprogramming is a must on my list of language requirements. It puts you in control to extend the language to suit your projects needs and lets you write powerful libraries that would be otherwise impossible. I have a strong web development background, and when I started with Elixir, I immediately realized how well suited it would be for a web framework. Phoenix was born out of the realization that I could have the best of both words in a web framework: a language that makes it a joy to write applications, with a runtime that is fast and scalable. With Elixir, Phoenix doesnt have to choose between productivity and scalability. Metaprogramming gives us both.