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Free Microservices Course

Microservices Architecture Tutorial

Learn how to design, build and run microservices step by step. Clear explanations, diagrams and working Spring Boot examples for every important pattern, from service decomposition to resilience, security and deployment.

Start Learning View Learning Path
  • Step-by-step learning path
  • Explained with visual diagrams
  • Real Spring Boot code

What Are Microservices?

Microservices architecture builds an application as a set of small, independent services. Each service owns one business capability (such as orders, payments or users), has its own database, and can be developed, deployed and scaled on its own. Services work together over the network using APIs and events.

UnitOne service per business capability
DataEach service owns its database
CommunicationREST, gRPC and events
DeploymentIndependent, often in containers

Compare monolithic and microservices architecture

What You Will Learn

  • When to choose microservices, and when a monolith is better
  • How to split a system into services with Domain-Driven Design
  • Synchronous and asynchronous communication, and event-driven design
  • Managing data with database per service and the Saga pattern
  • Resilience with circuit breakers, retries, timeouts and bulkheads
  • Service registry, service discovery and the API Gateway
  • Securing services with JWT, OAuth 2.0 and RBAC
  • Observability, testing and deployment strategies
  • Answering microservices interview questions with confidence

Who this is for

Java and Spring Boot developers moving from monoliths to microservices, backend engineers building distributed systems, and anyone preparing for microservices interviews.

Prerequisites

Core Java, basic Spring Boot, RESTful web services, and simple SQL or NoSQL database use.

Microservices Architecture at a Glance

Clients send requests to an API Gateway, which routes them to the right service. Each service has its own database. Services find each other through a service registry, share events through a message broker, and are protected by resilience patterns and centralized monitoring.

API GatewayOne entry point for all clients Database per ServiceEach service owns its data Service RegistryKeeps track of running services Event-Driven ArchitectureServices react to events Circuit BreakerStop failures from spreading Saga PatternTransactions across services

Microservices Learning Path

Follow the tracks in order, or jump to the pattern you need. Topics marked "coming soon" are being written and will be linked here as they are published.

Benefits and Challenges

Benefits

  • Teams develop and release services independently
  • Scale only the services that are busy
  • A failure in one service does not stop the others
  • Choose the best technology for each service

Challenges

  • Network calls can be slow or fail
  • Data consistency across services is harder
  • More infrastructure, monitoring and deployment work
  • Testing and debugging span many services

Learn how to handle the common challenges