Bath Tub Duck

A duck swimming program puzzle:

Instructions:

• You're the yellow duck
• Peck the big bubbles to get "a new beginning" / "checkpoint"
• Green ducks peck back
• Boats are sturdy... use 2 pecks
• The sub1 program is run every time "sub1" is listed in the main program.
• Peck 4 bubbles to win!
• (but the game doesn't have an ending)