A golden rectangle of sunlight trembled on the café terrace’s wet tiles. I’m Ostap, a scruffy dog with the expression of someone who has never approved of mornings, and I was waiting while my owner, Olena, bought coffee. She tied my leash to a light metal chair and disappeared through the door.

A gust of wind lifted an empty croissant bag from the next table. The paper wrapped gently around my muzzle and smelled of butter. I stepped back to investigate this gift from fate, but the chair slid after me. I took another step. It moved again, scraping the tiles with the determination of a waiter at closing time.

I decided to get away from the suspicious furniture more quickly. The chair sped up too. The bag covered my eyes, so I followed Olena’s scent straight toward the door. The chair swung sideways and became wedged in the entrance, leaving me outside, Olena inside, and the entire queue silently observing our family engineering project.

Olena asked me to back up. I obeyed, the chair slipped free, and the bag fell from my face. She untied the leash and found one croissant crumb inside it. She gave it to me. So the coffee was hers, while I got paid for moving the furniture. At last, the human payment system made sense.