They don't collide because the file names include more than just the number. And yes, manually renumbering is exactly what you'd have to do. Timestamps obviate

They don't collide because the file names include more than just the number. And yes, manually renumbering is exactly what you'd have to do. Timestamps obviate that. Theoretically, you can still have collisions (two migrations alter the same column, eg) or violated prereqs this way, so some communication is still required, but not to the degree before.