Coordination patterns

Ideally, microservices should be capable of doing a business unit of work. However, in some business scenarios, microservices have to leverage other services as a dependency, or as a composition. For example, consider a credit card payment that first debits a savings account and then credits a card account. In this case, the two underlying services, such as debit and credit, could be exposed by the respective savings account and credit card domains and coordination is required between them.