[falkensmaz3]

They exist. They are locked behind the firewalls of corporate America and Europe, and their engineers are generally forbidden to discuss it in public. OSS developers don't build software this way. Primarily because most generally useful (and therefore successful) OSS is not business domain-centric, and does not benefit from these patterns.

As one of those engineers that's forbidden to talk in public, I can assure you these patterns are extremely useful to keep valuable software viable, extensible, and maintainable for 15+ years. I just can't drop any specifics because IP lawyers are assholes.

[rswail]

I can't show you, but if you travel in Bangkok and use LINE Pay, then you're using one.

Combination of CQRS, event sourcing and kafka.

And I agree with falkensmaz3, they definitely do exist and they work much better in terms of defining the business domains and the way(s) the business "Nouns" interact with each other.

[orangehacker2]

I asked specifically about "Hexagonal, Onion, or Clean architecture".

CQRS is another story, it is relatively widely used and very handy in certain scenarios.

Is LINE Pay designed in a form of some kind of onion architecture?

[fruit2020]

What do you do in a code base 15 years old?

[falkensmaz3]

The same things you do in a code base 3 years old. We've just made it fashionable to evolve a code base until we hit a wall, toss it in the trash, and start over with the next "modern" tech that will eliminate the problems of the previous code base. Rinse/repeat.

If the business still exists and is continuing to evolve 15 years later, why shouldn't the code base?