eUTxO Fundamentals

Overview

eUTxO Fundamentals is a free eBook that teaches new developers how to write smart contracts, the small programs that run on a blockchain and carry out an agreement automatically¹. It walks a reader from installing the first tools to building a working marketplace, with exercises and worked solutions along the way². Each of the six programming languages has its own marketplace section, so readers can compare approaches side by side³.

The book focuses entirely on Cardano, and its full title is eUTxO Fundamentals: Building Cardano Smart Contracts. Developer Raul Antonio Rosa Padilla, known on GitHub as elRaulito, wrote it⁴. Project Catalyst, Cardano's community-voted grant program, funded the book twice: a Fund 11 proposal paid for the original edition⁴, and a Fund 14 proposal added chapters on Plutarch, another smart contract language, and on growing on-chain linked lists and merklized validators, written with developer Seungheon Oh⁵.

Key Features

• A guided path from setup to a real app. Early chapters cover wallets and test networks (practice copies of Cardano that use free test ADA) and treat running a node (software that connects to and checks the blockchain) as optional⁶, before later chapters build a full marketplace contract³.
• Six languages to choose from. eUTxO Fundamentals covers Plutus, Helios, Aiken, OpShin, plu-ts, and Plutarch, with OpShin in Python, plu-ts in TypeScript, Plutus and Plutarch in Haskell, and Helios using a C-like syntax⁷.
• How Cardano tracks money. A dedicated chapter explains the eUTxO model, where funds sit in separate outputs that can carry their own data and spending rules⁸, and contrasts it with the account-balance model used by Ethereum⁹.
• Governance and larger-app techniques. Later chapters show how to write contracts that take part in Cardano's on-chain governance¹⁰, plus design patterns for bigger applications, such as on-chain lists that can keep growing¹¹.
• Practice built in. The getting-started chapter covers security best practices and ends with exercises¹², and the solutions sit in their own section at the back of the book².

What to Expect

Readers download eUTxO Fundamentals as a light PDF and a dark PDF¹³. The GitHub repository holds the LaTeX source, the plain-text files that produce the PDF¹⁴.

Newcomers can read front to back. The book opens with an overview of Cardano's history and design and why smart contracts matter¹⁵, moves through tools and the eUTxO model, and closes with a glossary². The Fund 14 proposal names developers arriving from Bitcoin and Ethereum as target readers⁵.

The code examples that connect a website to a wallet use MeshJS, a TypeScript toolkit for building Cardano transactions and wallet connections¹⁶. The book is released under the Academic Free License 3.0¹⁷, and the README invites readers to report problems or suggest changes through GitHub issues and pull requests¹.