> Microservices is a service-oriented software architecture in which server-side applications are constructed by combining many single-purpose, low-footprint network services.

Gonna stop you right there.

Microservices have nothing to do with the hosting or operating architecture.

Martin Fowler who formalized the term, Microservices are:

“In short, the microservice architectural style is an approach to developing a single application as a suite of small services, each running in its own process and communicating with lightweight mechanisms, often an HTTP resource API. These services are built around business capabilities and independently deployable by fully automated deployment machinery”

You can have an entirely local application built on the “microservice architectural style.”

Saying they are “often HTTP and API” is besides the point.

The problem Twilio actually describe is that they messed up service granularity and distributed systems engineering processes

Twilio's experience was not a failure of the microservice architectural style. This was a failure to correctly define service boundaries based on business capabilities.

Their struggles with serialization, network hops, and complex queueing were symptoms of building a distributed monolith, which they finally made explicit with this move. So they accidentally built a system with the overhead of distribution but the tight coupling of a single application. Now they are making their foundations of architecture fit what they built, likely cause they poorly planned it.

The true lesson is that correctly applying microservices requires insanely hard domain modeling and iteration and meticulous attention to the "Distributed Systems Premium."

https://martinfowler.com/microservices/

Please don’t fall into the Fowler-said-so trap.

Just because he says something does not mean Fowler “formalized the term”. Martin wrote about every topic under the sun, and he loved renaming and or redefining things to fit his world view, and incidentally drive people not just to his blog but also to his consultancy, Thoughtworks.

PS The “single application” line shows how dated Fowlers view were then and certainly are today.