Building Your Own Roguelike

Building Your Own Roguelike: A Practical Guide takes you on an authentic journey from your first playable prototype to a complete, functional roguelike game. This is not a theoretical guide or a simplified tutorial. It is the real story of building Vanilla Roguelike over five years, complete with mistakes, breaking points, and architectural evolution.

The Journey Begins with Algorithms

The book starts where the project began: with maze generation. You will implement multiple algorithms, including Binary Tree, Aldous-Broder, Recursive Backtracker, and Recursive Division, to understand graph theory, spanning trees, and procedural generation. Each algorithm teaches different principles: some create long corridors, others produce boxy mazes.

The Architecture Problem: When Simple Stops Working

Early prototypes work fine when everything fits in one class. But as features multiply, the code becomes unmaintainable. This book takes you through the breaking point where the naive approach fails, helping you recognise the same problems in your own projects.

You will learn why Entity-Component-System (ECS) architecture solves these problems. ECS is not just a game development pattern. It is a fundamental approach to building scalable software. The book breaks down ECS into digestible pieces: entities as identifiers, components as data containers, and systems as behaviour processors.

Building Complete Game Systems

The middle chapters guide you through implementing real game systems: input handling, movement with collision detection, turn-based combat, inventory management, monster AI, and event-driven architecture. Each system is built iteratively. You start with the simplest version that works, then add complexity as needed.

Real-World Lessons from Real Mistakes

What sets this book apart is its honesty about the development process. You will learn about the breaking point where the original architecture could not support new features, the refactoring that saved the project, and the architectural decisions that enabled growth.

Why Build from Scratch?

Using a game engine teaches you the engine. Building from scratch teaches you the fundamentals. This book focuses on understanding how games work at their core: how algorithms generate content, how architecture enables features, and how systems communicate. The code examples use Ruby, but the concepts are language-agnostic.

Who This Book Is For

Intermediate to advanced programmers who want to understand game development, algorithms, and architecture through hands-on practice. Computer science students will find practical applications for graph theory, data structures, and design patterns. Game developers will gain deep understanding of ECS architecture and procedural generation.

Five parts. Twenty-two chapters. From your first prototype to a complete roguelike with procedural generation, combat, inventory, AI, and event-driven architecture.