Production Server After Refactoring Working Code

You know that code that's been running flawlessly for 5 years? The one written by that dev who left the company and didn't document anything? Yeah, some hotshot just decided it needed "optimization" and "clean architecture." Now your Slack is blowing up, the CEO is calling, and somewhere a database is crying. This is why we have the sacred developer commandment: "If it ain't throwing errors, don't fix it." Nuclear meltdown is just nature's way of saying you should've left that legacy spaghetti code alone.