[bitmapbrother]

I'm looking at their GutHub repository and pretty much the majority of the big boy code was lifted from Android.

  AsteroidOS/android_system_core  
  AsteroidOS/android_frameworks_native  
  AsteroidOS/android_bionic  
  AsteroidOS/android_external_skia  
  AsteroidOS/android_hardware_libhardware  
  AsteroidOS/android_build

While the fluff such as the following is all theirs:

  AsteroidOS/asteroid-calculator

[petecox]

Most alternative firmwares bootstrap AOSP to some degree in some way for hardware support or adb/fastboot to shoe-horn an alternative ROM.

Reusing some low level code does not an Android make.