Xun (Brian) Wu is a senior blockchain architect and consultant. He has written eight books on popular fields within blockchain, such as Hyperledger and Ethereum (from beginning to advanced), published by O'Reilly and Packt. Brian has 18+ years of hands-on experience across various technologies, including blockchain, big data, the cloud, systems, and infrastructure UI. He has worked on more than 50 projects in his career.

Zhihong Zou has more than 20 years of software architecture, design, and development experience in the telecommunication and healthcare industries. As a seasoned enterprise and solution architect, and a thought leader in blockchain, business process management, big data, AI, and machine learning, he has leveraged emerging technologies to solve complex real-world business problems. He holds a master's degree in computational mathematics and a master's degree in computer science. He has published several papers on numerical computation in renowned academic journals. I would like to thank my wife Yufang and my son Kevin for their understanding, encouragement, support, and patience throughout this journey. I appreciate all the sacrifices you made so that I could complete the book.

Dongying Song has more than four years of extensive hands-on experience in blockchain, Ethereum, big data, machine learning, and data science. As an experienced software engineer and data scientist, she has worked for a top-tier bank and pharmaceutical companies. Dongying holds a master's degree in statistics from Columbia University and majored in mathematics during her undergraduate years. Her recent activities have focused on blockchain, Ethereum, and smart contract developments.