Why it exists
I wanted a place where architecture arguments have consequences. A diagram can make almost anything look clean. A cluster that runs for months will tell you which parts were actually clear, which parts were wishful, and which parts only worked because I remembered the trick.
The lab gives me a controlled place to practice platform operations without pretending it is harmless. Change management, rollback, observability, runbooks, drift, and backup testing all show up eventually. So do the failures: the worst one earned a written root-cause analysis, the same as production would.