Microservices
Microservices is a recent term used to describe systems where the logic tier of the three-tier pattern is composed of several smaller services that communicate with language-agnostic protocols.
Typically, the language-agnostic protocol is HTTP based, commonly JSON REST, but this is not mandatory. There are several possibilities for the protocol layer.
This architectural design pattern lends itself well to a Continuous Delivery approach since, as we have seen, it's easier to deploy a set of smaller standalone services than a monolith.
Here is an illustration of what a microservices deployment might look like:
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We will evolve our example towards the microservices architecture as we go along.