Great art, startling boss, dodge mechanic is super silly and fun. The lay out does teach you nicely how to use it, and it's great you can use arrow keys for those more comfortable using two hands for the jump/dash (left hand) --- movement (right hand).
I can't tell if it's intentional that you have to jump to be able to get onto the main boss platform. If it is, it's a nice way to ensure the player has to learn all the mechanics before getting to the bird.