The first moat is usually capital expenses. Look at AWS - they're built mainly on open source software so it is obviously trivial to re-implement a lot of their

The first moat is usually capital expenses. Look at AWS - they're built mainly on open source software so it is obviously trivial to re-implement a lot of their core functionality. But it is hard to compete with the sheer amount of capital. The software aspects make a big difference too, but it is actually quite easy to re-implement software. Something like git for example was built rapidly (3 months?) after a few years of using other VCS to learn what it needed to do.