I picked this up after I had already been talking at conferences on this very topic of going from monolith towards microservices, with a modular monolith as a possibility.
This book covers the patterns used in transitioning between monoliths, modular monoliths, and microservices. From general design patterns to migration design patterns and data design patterns, this book has a lot of guidance on the various patterns to use on these topics – what the pattern is, how it works, and when to use it. He uses relatable examples and great studies of others who have implemented them in their monolith migrations.
If you have to deal with migrating between these and want a better understanding of the patterns using in these migrations, I highly recommend this book.
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