Comment by Tainnor

Microservices are distributed and distributed systems are inherently more complex than non-distributed ones.[0]

> A microservice can be as simple as studying it's inputs and outputs and nothing more. All of which can be observed via tracing, logging or whatever you prefer, either on a sampled-basis, only on errors, or all the time.

In a statically-typed monolith, function calls are typed, I can jump to the declaration site with a mouse click and if I pass the wrong type, the code won't compile. That's way easier than "you can observe the inputs and outputs" (and hope that your observations generalise sufficiently). And yes, there are solutions for this (contract tests, Avro schemas, etc.), but they are inherently more complicated (maybe the most interesting idea I've seen in this space is Unison[1], but that's not gonna gain a lot of traction anytime soon, I predict).

Of course, microservices have valid use cases, but they come at a significant cost. I don't understand how one can argue that that cost doesn't exist.

[0]: https://en.m.wikipedia.org/wiki/Fallacies_of_distributed_com...

[1]: https://www.unison-lang.org/