Summary

In this chapter, I have used a short historical approach (a detailed one would be a book in itself) to explain what the stakes at play are in service orientation and how this seemingly simple yet hard-to-define word of service has been implemented in the past decades. We are definitely not at the end of the story yet, but nowadays, it seems the best approach is to use REST APIs with a middleware, reduced as much as possible through the use of norms and standards. This not only avoids the costly mediation connectors that translate one format to another, since everybody in the interaction talks the same language but also helps us know whether our design is the right one since consortiums and experts have thought a lot about this business domain.

Standardized APIs are what make it easy today to change some parts of important information systems without breaking them. They allow for international banking, much more efficient insurance systems, simplified travel abroad, and many...