Java Application Architecture: From Monolith to Microservices

The book "Java Application Architecture: From Monolith to Microservices" is a practical guide for developers who want to learn how to design complex, scalable, and maintainable systems in Java. Alexey Voronov, an author with 15 years of experience in enterprise solution development, shares proven approaches and real-world cases.

What is this book about?

The book covers the full lifecycle of a Java application architecture: from choosing the initial structure to transitioning to microservices. You will learn:

• How to properly design a monolith that won't turn into a "swamp" in a year.
• Which patterns (CQRS, Event Sourcing, Saga) to use and when.
• How to implement Domain-Driven Design (DDD) in a real project.
• Ways to decompose a monolith into microservices without stopping development.
• How to organize CI/CD, containerization (Docker, Kubernetes), and monitoring.
• Common architect mistakes and how to avoid them.

Who is this book for?

The book is intended for:

• Java developers at the Middle and Senior level who want to transition to architectural roles.
• Team leads and architects looking for structured approaches to design.
• Technical managers who want to understand how architectural decisions are made.

What will you learn?

After reading, you will be able to:

• Choose the appropriate architectural style (monolith, modular monolith, microservices).
• Design bounded context boundaries and aggregates in DDD.
• Implement asynchronous interaction via message brokers (Kafka, RabbitMQ).
• Refactor legacy code without losing functionality.
• Set up automated testing, deployment, and monitoring of distributed systems.

Why should you read it?

The book contains not only theory but also ready-made code examples in Java (Spring Boot, Hibernate, Micronaut). Each chapter ends with a practical task and a checklist for auditing an existing project. This is not just another abstract book — you can immediately apply the knowledge in your work.

If you want to stop "putting out fires" in production and start building systems that are easy to develop and maintain — this book is for you.