Last year I got a new MacBook Pro. 512GB SSD. I figured that was plenty — I'm not storing raw video footage or anything. I write code. Four months later, macOS told me I was running low on disk space. I opened System Settings > Storage and stared at the breakdown. "Developer" was the single largest category, bigger than my music library, photos, and documents combined. But macOS doesn't tell you what in that category is eating the space. It just shows you a gray bar and shrugs. So I started digging. I opened Terminal and started checking folder sizes manually. What I found was staggering: over 200GB of cached build artifacts, old container images, orphaned virtual environments, and dependency folders for projects I hadn't touched in months. That investigation — and the frustration of repeating it every few months — is why I eventually built MegaCleaner . But before I talk about that, let me show you exactly where your disk space is going.…