I built my own IAP backend instead of using RevenueCat — what 3 weeks of pain taught me

I'm shipping a subscription-based React Native app and went through the "do I use RevenueCat or roll my own?" question that probably every solo RN dev hits. I ended up rolling my own, ran into more edge cases than I expected, and eventually pulled the working backend into an MIT package. Sharing the post-mortem in case it saves someone else the same weeks. Why not RevenueCat To be clear — RevenueCat is good. For a lot of apps it's the right call. Two things pushed me off it: Revenue share scales