> i don't have to rewrite major swaths of code because somebody else decided to change the abstraction. You also could solve this concern by using an existing

> i don't have to rewrite major swaths of code because somebody else decided to change the abstraction. You also could solve this concern by using an existing library, then simply not upgrade when new versions come out. After all, if you can write it all yourself, surely you also could fork from your starting version if you ever need a change? I look at it similarly to how I buy a bicycle. Sure, I could buy all the individual parts and assemble my own bike. Or I can buy a complete bike that is close to what I want, then update a part here and there as needed. After all, the goal is to ride the bike, not spend all my time tinkering with parts in my garage. Same with code - sure, I could write it all myself. Or I can use existing work to skip all that, and focus on just what my product needs. And still dive deep and make changes when the business needs the change.