The world's first Fedify book, Practical Fedify: Introduction to ActivityPub Microblog Development (実践Fedify——ActivityPubマイクロブログ開発入門), has been published in Japan. This is also the first book I have ever published, and it feels quite surreal that my first book is in Japanese rather than my native language, Korean. This book is an expanded version based on the official English Fedify tutorial, Creating your own federated microblog, with various additions. Yumetsuki Mama (ゆめつきママ) worked on the cute book cover illustration, which features the Fedify dinosaur mascot, Misskey's mascot Ai-chan, and the Mastodon mascot together. It is scheduled to be published in both e-book and print formats on the 22nd by Impress NextPublishing. See also the Amazon Japan.