Once the dust had settled, the kitchen opened a little bar out front, with four stools, two lanterns and a glass jar at the end of the counter.

“Who gets to sit at the bar?” asked Maki.

“Anyone who brings SUSHI,” said the new head cook. “Leave your SUSHI in the bar and we’ll give you an xSUSHI token in return. And every time anybody, anywhere in the kitchen, makes a swap, a tiny slice of the fee goes into that jar.” Uni, who had come over for dinner, raised one very elegant eyebrow.

The cook drew a pie on a napkin. “Say Wasabi swaps $1,000 of rice for tuna. The fee is 0.3%, which is $3.”

“Five-sixths of that, 0.25% or $2.50, stays in the pool, for the liquidity providers. That’s why people bring bowls.”

“The last sixth, 0.05% or 50 cents, goes to the bar. The kitchen turns it into SUSHI and drops it in the jar. Fifty cents doesn’t sound like much,” the cook admitted. “But a busy kitchen makes a lot of swaps.”

Run the kitchen for a day. Choose how much gets swapped and watch the fees pile up: most of it in the pool for the liquidity providers, and a little in the bar’s jar.

Then try a really busy day. A tiny slice of a huge number is still a big number, which is the whole idea behind the bar.

Everything was going beautifully. Then, one afternoon, the price of tuna went up in town, and Maki learned a sad new phrase.