Hello, I’ve added a new free (online) book to the Yuki & Moto Press Bookshelf. Let’s welcome: Programming Blockchains Step-by-Step from Scratch (Zero) in Ruby. Starting with Crypto Hashes… The contents includes: (Crypto) Hash - (Crypto) Block - (Crypto) Block with Proof-of-Work - Blockchain - Blockchain Broken? - Timestamping - Mining, Mining, Mining - Bitcoin, Bitcoin, Bitcoin - (Crypto) Block with Transactions (Tx) - References / Links. Note: The manuscript source includes many single-file ruby script samples. Happy mining and blockchaining with Ruby. PS: Did you know? You can build online books and bookshelves with ruby - use the jekyll machinery with octobook themes