Building Blockchain Apps

A Developer's Guide to Blockchain Programming Fundamentals Blockchain development is entering a period of explosive growth, as real applications gain traction throughout multiple industries and cryptocurrencies earn greater acceptance throughout the financial sector. Blockchain represents one of the most promising opportunities for developers to advance and succeed. Building Blockchain Apps is an accessible guide to today’s most advanced and robust blockchain programming models and architectures. Building on his pioneering experience, Michael Juntao Yuan covers a wide range of blockchain application development paradigms. The book starts with a concise introduction to blockchain and smart contract technologies. It then guides you through application development on Ethereum-compatible smart contract platforms. Ethereum is the largest and most robust blockchain ecosystem in the world. Coverage includes Ethereum topics such as tools, application frameworks, internal data structures, external data interfaces, and future roadmap An introduction to new blockchain data protocol based on ElasticSearch, which provides insights into the current state of smart contracts and enables new application designs How to build an application-specific smart contract protocol by modifying and customizing the open source Ethereum Virtual Machine and its programming language tools How to extend and support language features that are most suitable for particular kinds of smart contracts (e.g., smart contracts for e-commerce marketplaces) with the open source Lity project How to customize and change the blockchain consensus layer beneath the application layer via the popular Tendermint and Cosmos SDK frameworks A survey of cryptocurrency and financial topics from the developers’ point of view, providing an analytical framework for valuating cryptocurrencies and explaining the roles of crypto exchanges Register your book for convenient access to downloads, updates, and/or corrections as they become available. See inside book for details.

Build decentralized applications using BlockchainÕs core technology Ê KEY FEATURESÊÊ _ Explore the engineering mechanism of Blockchain, Cryptocurrency, and Ethereum. _ Know-how of peer-to-peer networks, IPFS, and decentralised databases. _ Explore the working of DApps and build your own blockchain app. DESCRIPTIONÊÊ Blockchain is a revolutionary technology that shook the core of the finance world. However, Blockchain is not just about Cryptocurrency. This book focuses on Blockchain, its features, and the core technologies that are used to build the Blockchain network. In the first section, you will learn about Blockchain in-depth. Then, the book covers the two most popular Cryptocurrencies - Bitcoin and Ethereum. You will learn how these currencies work and how you can build your applications using these currencies. Moving on, you will learn about the decentralized databases. Decentralized databases can be used to build next-generation software applications. You will learn about various databases and how to use them in detail. Lastly, you will learn how the existing decentralized applications work, their architecture, and how they are incorporated into the application for the end-user. WHAT YOU WILLÊ LEARN _ Learn to build your own P2P network. _ Cutting-edge coverage on how cryptocurrency works. _ Learn smart techniques to develop your own DApps on Ethereum platform. _ Learn to use decentralized databases including OrbitDB. WHO THIS BOOK IS FOR This book is for anyone who wants to become a Blockchain developer or wants to build an application using Blockchain. Full stack developers, software engineers, web programmers, and beginners who are interested in Blockchain can find this book a true handy guide to begin their career in Blockchain.Ê TABLE OF CONTENTSÊÊ 1. Introduction to Blockchain and decentralized network 2. Ethereum, Smart Contracts and DApps 3. Interplanetary file system 4. OrbitDB - Peer to peer distributed database 5. BigchainDB 6. TiesDB 7. BluZelle 8. Amazon QLDB 9. OpenBazaar 10. DTube 11. Ocean protocol

Develop real-time practical DApps using Ethereum and JavaScript About This Book Create powerful, end-to-end applications for Blockchain using Ethereum Write your first program using the Solidity programming language Change the way you think and design your applications by using the all new database-Blockchain Who This Book Is For This book is for JavaScript developers who now want to create tamper-proof data (and transaction) applications using Blockchain and Ethereum. Those who are interested in cryptocurrencies and the logic and database empowering it will find this book extremely useful. What You Will Learn Walk through the basics of the Blockchain technology Implement Blockchain's technology and its features, and see what can be achieved using them Build DApps using Solidity and Web3.js Understand the geth command and cryptography Create Ethereum wallets Explore consortium blockchain In Detail Blockchain is a decentralized ledger that maintains a continuously growing list of data records that are secured from tampering and revision. Every user is allowed to connect to the network, send new transactions to it, verify transactions, and create new blocks, making it permission-less. This book will teach you what Blockchain is, how it maintains data integrity, and how to create real-world Blockchain projects using Ethereum. With interesting real-world projects, you will learn how to write smart contracts which run exactly as programmed without any chance of fraud, censorship, or third-party interference, and build end-to-end applications for Blockchain. You will learn about concepts such as cryptography in cryptocurrencies, ether security, mining , smart contracts, solidity, and more. You will also learn about web sockets, various API services for Ethereum, and much more. The blockchain is the main technical innovation of bitcoin, where it serves as the public ledger for bitcoin transactions. Style and approach This is a project-based guide that not only gets you up and running with Blockchain, but also lets you create intuitive real-world applications that will make you an independent Blockchain developer.

Summary Building Ethereum Dapps introduces you to decentralized applications based on the Ethereum blockchain platform. In this book, you'll learn the principles of Dapps development by rolling up your sleeves and actually building a few! Foreword by Thomas Bertani. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Imagine unbreakably secure applications that handle personal and business transactions without any central agency controlling the process. Decentralized applications, or Dapps, do just this, shifting power to users. The Ethereum blockchain platform provides the tools you need to build Dapps, including an innovative "smart contracts" model and Solidity, a Dapp-aware JavaScript-like programming language. About the Book Building Ethereum Dapps teaches Dapps development on the Ethereum blockchain platform. You'll begin with a mental model of how Dapps operate, and then dive into designing and implementing smart contracts in Ethereum's Solidity language. You'll explore Ethereum smart contract development tools, like Truffle and Web3, and pick up best practices for design and security. Practical exercises throughout give you valuable hands-on experience. What's inside Ethereum's key components Implementing smart contracts in Solidity Communicating with a smart contract in Web3 Developing Dapps with Truffle Best practices for design and security improvement About the Reader For developers with intermediate experience in JavaScript or an OO language. Familiarity with blockchain concepts is helpful. About the Author Roberto Infante is a software development consultant who specializes in finance. He currently works on financial risk management systems and on blockchain technology. Table of Contents PART 1 A first look at decentralized applications Understanding the blockchain The Ethereum platform Deploying your first smart contract PART 2 Programming smart contracts in Solidity Writing more complex smart contracts Generalizing functionality with abstract contracts and interfaces Managing smart contracts with Web3.js PART 3 The Ethereum ecosystem Unit testing contracts with Mocha Improving the development cycle with Truffle Putting it all together: Building a complete voting Dapp PART 4 Making a Dapp production ready Security considerations Conclusions

This book addresses what software architects and developers need to know in order to build applications based on blockchain technology, by offering an architectural view of software systems that make beneficial use of blockchains. It provides guidance on assessing the suitability of blockchain, on the roles blockchain can play in an architecture, on designing blockchain applications, and on assessing different architecture designs and tradeoffs. It also serves as a reference on blockchain design patterns and design analysis, and refers to practical examples of blockchain-based applications. The book is divided into four parts: Part I provides a general introduction to the topic and to existing blockchain platforms including Bitcoin, Ethereum, and Hyperledger Fabric, and offers examples of blockchain-based applications. Part II focuses on the functional aspects of software architecture, describing the main roles blockchain can play in an architecture, as well as its potential suitability and design process. It includes a catalogue of 15 design patterns and details how to use model-driven engineering to build blockchain-based applications. Part III covers the non-functional aspects of blockchain applications, which are cross-cutting concerns including cost, performance, security, and availability. Part IV then presents three detailed real-world use cases, offering additional insights from a practical perspective. An epilogue summarizes the book and speculates on the role blockchain and its applications can play in the future. This book focusses on the bigger picture for blockchain, covering the concepts and technical considerations in the design of blockchain-based applications. The use of mathematical formulas is limited to where they are critical. This book is primarily intended for developers, software architects and chief information officers who need to understand the basic technology, tools and methodologies to build blockchain applications. It also provides students and researchers new to this field an introduction to this hot topic.

Ethereum represents the gateway to a worldwide, decentralized computing paradigm. This platform enables you to run decentralized applications (DApps) and smart contracts that have no central points of failure or control, integrate with a payment network, and operate on an open blockchain. With this practical guide, Andreas M. Antonopoulos and Gavin Wood provide everything you need to know about building smart contracts and DApps on Ethereum and other virtual-machine blockchains. Discover why IBM, Microsoft, NASDAQ, and hundreds of other organizations are experimenting with Ethereum. This essential guide shows you how to develop the skills necessary to be an innovator in this growing and exciting new industry. Run an Ethereum client, create and transmit basic transactions, and program smart contracts Learn the essentials of public key cryptography, hashes, and digital signatures Understand how "wallets" hold digital keys that control funds and smart contracts Interact with Ethereum clients programmatically using JavaScript libraries and Remote Procedure Call interfaces Learn security best practices, design patterns, and anti-patterns with real-world examples Create tokens that represent assets, shares, votes, or access control rights Build decentralized applications using multiple peer-to-peer (P2P) components

Technology is constantly evolving, and blockchain is taking development to new places, as mobile did a decade ago – and Ethereum is the leading platform for creating this new wave of applications. This book reveals everything you need to create a robust decentralized application (more commonly known as DApp). Unlike other books on the topic, this one focuses on the web application layer, and guides you in creating great experiences on top of the Ethereum blockchain. You’ll review the challenges and differences involved in developing DApps as opposed to traditional web applications. After a brief introduction to blockchain history and Ethereum in particular, you’ll jump directly into building a sample decentralized application, to familiarize yourself with all the moving pieces. This book offers specific chapters on querying and rendering data from the blockchain, reacting to events, interacting with user accounts, sending transactions, managing gas, handling confirmations and reorganizations, and more. You will also find a chapter dedicated to Solidity that will give you the necessary means to understand and even build your own smart contracts. Other important topics covered include building backend servers that act as indexing layers, and managing storage efficiently with solutions like the interplanetary file system, or IPFS. Last but not least, you will find chapters that examine the biggest problems on Ethereum today: onboarding and scalability. These include the state of the art of the available strategies to tackle them, such as meta-transactions, smart accounts, ENS, state channels, sidechains, and more. What You'll Learn Connect to the blockchain from the browser and send transactions from client-sideBuild a web app that provides a read-only interface to a blockchain contract Create a wallet interface for arbitrary fungible tokens, displaying the user’s balance and allowing for simple transfers to other addressesDevelop a web app that stores large blobs of data off-chain, and keeps a reference to it on-chain (e.g. avatars, long text descriptions) Produce a web app that relies on a centralized server for indexing on-chain information to be presented to the user Who This Book Is For Web developers focused on client-side applications, with knowledge of JavaScript and HTML/CSS. You do not need any prior knowledge of Blockchain, Ethereum, or cryptocurrency.