Services must be cohesive. A service should implement a small set of strongly related functions.

▪ Services must be loosely coupled - each service as an API that encapsulates its implementation.

▪ "Decompose by Subdomain" pattern offer:

▪ Define services corresponding to Domain-Driven Design

(DDD) subdomains.

▪ DDD refers to the application’s problem space, the business

as the domain. A domain is consists of multiple subdomains.

▪ Each subdomain corresponds to a different part of the business.

https://medium.com/design-microservices-architecture-with-patterns/decomposition-of-microservices-architecture-c8e8cec453e#:~:text=Microservices%20Decomposition%20Pattern%20%E2%80%94%20Decompose%20by%20Subdomain&text=DDD%20refers%20to%20the%20application's,different%20part%20of%20the%20business.