Comment by codethief

> Building and maintainance cost are not linear, especially when you inherit legacy code. The AOSP codebase isn't great, is 4x bigger than the Linux Kernel, and full of "Ship now, patch later" mess.

And yet the GrapheneOS devs seem to be managing just fine.

> But I agree that it is a significant endeavor.

Yes, in fact it is orders of magnitude more significant an endeavor that just building upon and improving the existing AOSP stack.