Part III: Building Real Software with AI

"The proof of vibe coding is in the shipping."

Parts I and II taught you what vibe coding is and how to communicate with AI effectively. Now it is time to build. Part III is the largest section of this book, spanning nine chapters and covering every major domain of practical software development. By the end, you will have built command-line tools, web frontends, backend APIs, databases, full-stack applications, API integrations, test suites, and documentation — all with AI as your development partner.

Chapter 15 starts with command-line tools and scripts — the bread and butter of practical programming. You will learn argument parsing, configuration management, logging, file processing, progress bars, error handling, and packaging, producing professional CLI applications that solve real problems.

Chapter 16 moves to web frontend development. Even as a Python-focused developer, you will learn to generate HTML, CSS, and JavaScript with AI, build React components, manage state, implement responsive design, and create complete frontend applications. AI bridges the gap between backend knowledge and frontend capability.

Chapter 17 covers backend development and REST APIs — the server-side foundation of modern applications. Using Flask and FastAPI, you will build APIs with proper routing, authentication, error handling, middleware, and OpenAPI documentation.

Chapter 18 introduces database design and data modeling. From relational database fundamentals through SQL, SQLAlchemy ORM, Alembic migrations, and schema design patterns, you will learn to build robust data layers that store and retrieve information reliably.

Chapter 19 integrates everything. Full-stack application development is where frontend meets backend meets database, and this chapter shows you how to plan, build, and deploy integrated applications — including authentication flows, file uploads, real-time features, and environment configuration.

Chapter 20 extends your reach to external APIs and integrations — OAuth flows, payment processing, email services, cloud storage, webhooks, and rate limiting. Modern applications rarely stand alone, and this chapter teaches you to connect them to the wider ecosystem.

Chapter 21 may be the most important chapter in this part: AI-assisted testing. Testing is more important, not less, when code is AI-generated. You will learn pytest, integration testing, property-based testing, test-driven development with AI, mocking, and coverage analysis.

Chapter 22 addresses debugging and troubleshooting — the inevitable companion to building software. You will learn to use AI as a debugging partner, analyzing error messages, stack traces, logs, and performance issues systematically.

Chapter 23 covers documentation and technical writing — READMEs, API docs, architecture decision records, docstrings, and user guides. AI excels at generating documentation, and this chapter shows you how to leverage that capability.

By the end of Part III, you will have the practical skills to build, test, debug, and document real software across the full stack. The projects you create will not be toys — they will be production-quality applications built with professional practices.