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Microservice decomposition patterns

Evolutionary patterns for breaking down your monolith into microservices

Topic: Programming
Sam Newman

Many people interested in adopting microservice architectures already have lots of valuable working software that uses different architectures. Rather than throwing all that away and undertaking a "Big Bang" rewrite, you can save time, headaches, and money by adapting what you already have and incrementally adopting a microservice architecture.

Join expert Sam Newman to explore a number of techniques that allow you to incrementally migrate from existing monolithic applications or vendor-based software to microservice architectures. You'll learn how to make the necessary architectural changes to adopt microservices without needing to resort to a "Big Bang" rewrite. Sign up today to discover how to keep your customers happy today while building a platform for tomorrow.

What you'll learn-and how you can apply it

By the end of this live online course, you’ll understand:

  • How to prioritize what to migrate first
  • How to keep your existing software running and serving customers while moving functionality to a new architecture
  • How to break down migration into multiple discrete steps

And you’ll be able to:

  • Use a variety of migration patterns in different contexts to make adopting microservices easier
  • See architecture less as a static, nonchanging entity and more as something you must continuously change to make sure it’s fit for its purpose

This training course is for you because...

  • You're currently struggling with a large monolithic system.
  • You have a big COTS product you want to replace with your own solution.
  • You want to incrementally migrate toward a microservice architecture.


  • A basic understanding of microservices, equivalent to Microservice fundamentals (live online training course with Sam Newman)

Recommended preparation:

About your instructor

  • After spending time at multiple startups and 12 years at ThoughtWorks, Sam Newman is now an independent consultant. Specializing in microservices, cloud, and continuous delivery, Sam helps clients around the world deliver software faster and more reliably through training and consulting. Sam is an experienced speaker who has spoken at conferences across the world, and is the author of Building Microservices and Monolith to Microservices both from O'Reilly Media. Sam is also co-chair of the O’Reilly Infrastructure & Operations Conference.


The timeframes are only estimates and may vary according to how the class is progressing

Evolutionary architecture (45 minutes)

  • Group discussion: What state are you currently in: thinking of a move to microservices or already doing it? What's a good reason for a migration?
  • Lecture: How to frame a microservice transition; why the "Big Bang" rewrite is bad; how to prioritize transition
  • Break (10 minutes)

Application migration patterns (55 minutes)

  • Lecture: Migration pattern walkthrough—event decoration, composite calling, branch by abstraction, and the stranger pattern
  • Group discussion: How would you put one or more of these patterns to good use?
  • Q&A
  • Break (10 minutes)

Database migration patterns (55 minutes)

  • Lecture: The importance of not sharing schema; multiple database migration patterns; distributed transactions; CAP theory
  • Group discussion: Do you share schemas at the moment?
  • Wrap-up and Q&A