Monorepo vs Multirepo: How I Changed My Mind After Working on Real Projects

When I started building projects from scratch, I kept running into the same question over and over again: Should I use a monorepo or split everything into multiple repositories? For a long time, I thought I had a clear answer. Now I'm not so sure anymore. This is not a theoretical comparison. It's just how my opinion changed after working on real systems with real teams. At the beginning of my career, I loved monorepos. They felt simple and natural, especially when I was working alone or in a small team. Everything was in one place, and I didn't have to think too much about boundaries or versioning. I could change the frontend, update the backend, fix the tests, and ship everything in a single commit. One change, one result. No coordination, no compatibility concerns, no overhead. At some point I even started wondering why people bothered with multiple repositories at all. It felt like unnecessary complexity. That illusion didn't last. The first time my perspective really shifted was w