The Fallacies of Enterprise Computing is good throughout. It's hard to excerpt; here only some of the highlights:
- After building IT systems for more than sixty years, one would think we as an industry would have learned that “newer is not always better”. Unfortunately, this is a highly youth-centric industry, and the young have this tendency to assume that anything new to them is also new to everybody else. And if it’s new, it’s exciting, and if it’s exciting, it must be good, right? And therefore, we must throw away all the old, and replace it with the new.
- How is “the cloud” any different from “the mainframe”, albeit much, much faster and with much, much greater storage?
- [B]y using relational database constraints, the database can act as an automatic enforcer of business rules, such as the one that requires that names be no longer than 40 characters. Any violation of that rule will result in an error from the database. Right here, right now, we have a violation of the “centralized business logic” rule.
- despite the fact that many enterprise IT departments are building microservices, they then undo all that good work by then implicitly creating dependencies between the microservices with no mitigating strategy to deal with one or more of those microservices being down or out. This means that instead of explicit dependencies (which might force the department or developers to deal with the problem explicitly), developers will lose track of this possibility until it actually happens in Production--which usually doesn’t end well for anybody.
- The enterprise is a constantly shifting, constantly changing environment. Just when you think you’ve finished something, the business experts come back with some new requirements or some changes to what you’ve done already. ... [A]nything that gets built here should (dare I say “must”) be built with an eye towards constant-modification and incessant updates.
- The cloud has nothing magical in it that makes things scale automagically, secure them, or even make them vastly more manageable than they were before. You can derive great benefits from the cloud, but in most cases you have to meet the cloud halfway--which then means that the vendor didn’t make the problem go away, they just re-cast the problem in terms that make it easier for them to sell you things.
- No matter what the vendor/influencer tries to tell you, no matter how desirable it is to believe, there is no such thing as a “universal enterprise architecture”; not MVC, not n-tier, not client-server, not microservices, not REST, not containers, and not whatever-comes-next.