At GitLab a couple of years ago we had to fight the temptation to split the application up in hundreds of micro-services.

I'm glad we did and today GitLab has a big monolith but also a ton of services working together https://docs.gitlab.com/ee/development/architecture.html#com...

I did an interview about this yesterday https://www.youtube.com/watch?v=WDqGaPGBZ9Y