[Seb-C]

In modern development you should actually use micro-services. It is so useful that you can use it for everything. For example, if you find out that you have too many different functions to validate an integer, write a micro-service that validates integers!

And because the new service crashes when you input a non-integer string, please catch and ignore the exception client side (we'll fix it later).

[Cthulhu_]

Definitely don't spend any time on things outside the scope of your microservice, your code is wonderful and pure and any pesky architect that wants to argue about integration with the rest of the architecture just doesn't appreciate your Art.

On that note, as architect make sure to insist on perfect implementations of specs, like the JSON:API media type (https://jsonapi.org/format/), or use older formats like XML and insist on perfect implementations. A simple "validate number" microservice will have so many nonfunctional requirements it'll take years to develop.