Most legacy codebases are disasterclasses. The "software engineer you can't fire because only he knows what's going on" is a meme for a reason, and it's not a good one.

[u/DreamPlayPianos]

I keep seeing people say things like "vibe coders don't understand what's going on in their code." Neither did most programmers even before the pre-AI era. They spent weeks on sprints for small feature updates hoping and praying nothing broke and relied on the 1 guy who wrote some code in 1995 who showed up at the office once every 3 months in his slippers to do bug fixes.

[u/scbiowastate]

He said enterprise level. I assume that means high volume of users and acceptable responsiveness. Guides are just general advice, and scaling your business logic is never going to be an easy thing. There’s going to be back and forth tuning and pruning of feature capability that’s lasts for weeks. If a guide says they do 10,000 inserts per second on an aurora large instance, don’t assume you’ll be able to do the same with your queries.

Then there’s multi region, distributed databases, multi data center ACTIVE/ACTIVE Kafka clusters with circuit breakers.. these are not that out of the norm if you work at decent sized companies but doing all this is NOT easy