On market day the whole odd little town squeezes into the square. There are stalls selling tokens in little jars, a gallery where every painting is a one-off, a brass band, a popcorn cart, and a booth with a sign that reads FEES · PAY TINY.

Right in the middle, standing on an upturned crate, was Mr. Croak. “Lily Pad Futures!” he croaked. “Umbrellas for fish! Insurance against Tuesdays!” Vera, walking past, wrote down every word.

Every Solana transaction pays a small fee in SOL, the network’s own currency. SOL is counted in tiny units called lamports, and a billion of them make one SOL. Each signature on a transaction has a base fee, and if you’re in a hurry you can add an optional priority fee to ask the current leader to fit you in sooner.

Anyone can also make their own tokens with Solana’s token programs. An NFT is a token made to be one of a kind, so the gallery’s paintings are close cousins. And apps are programs, code kept on the ledger that anyone can call.

Which brings us to $SOLSTO, the ticker for this book’s project. It isn’t SOL and it doesn’t pay network fees, and this book promises nothing about its price, returns or uses. Mr. Croak tried to sell it as “guaranteed”. Vera took his megaphone away.

At the fee booth a clerk in very small glasses was weighing out lamports on a brass scale. “Nobody pays in whole SOL for a stamp,” she said. “We’d be here all week giving change.”

Have a go on the scale. Pick how many signatures a transaction needs and whether to add a priority tip, and you’ll see the fee in lamports and in SOL. The base fee is the documented 5,000 lamports per signature. The tip is your call. A real fee depends on the transaction and on how busy the network is at the time.

Toly paid, bought a bag of popcorn that came with no business plan whatsoever, and was halfway through it when every clock in the square stopped at once.