Mastering the Lightning Network is an O'Reilly Media book, by authors Andreas M. Antonopoulos (@aantonop), Olaoluwa Osuntokun (@roasbeef), Rene Pickhardt (@renepickhardt). It was published on Dec 21, 2021, in paperback and e-book, by O'Reilly Media. It is available everywhere that books are sold. This repository contains the manuscript of the book as published by O'Reilly Media, tagged as firstedition_firstprint. The book describes the Lightning Network (LN), a Peer-to-Peer protocol running on top of Bitcoin and other blockchains, which provides near-instant, secure, micro-payments. The book is suitable for technical readers with an understanding of the fundamentals of Bitcoin and other open blockchains. Mastering the Lightning Network is released under the Creative Commons CC-BY-NC-ND license, which allows sharing the source code for personal use only. You may read this book for free.