Zero Knowledge · Read

Chapter 2

Confirmation

The mempool had it in four seconds.

It showed up on a node in Frankfurt. The node could be anywhere, but she hoped it was on someone’s home machine even though that didn’t really matter. It was already relayed, sitting in the queue with thirty thousand strangers’ payments like it belonged there.

She kept staring at it hoping it would vanish. The bile rose in her throat. She grabbed the trash can by her desk and threw up in it.

“Breathe. Take a deep breath,” Samantha said out loud to the empty room.

The thoughts came fast. Replace it with a higher fee — no, the coins were already moving, you don’t get to move them twice. Find the miner — there was no miner, there were thousands, in rooms she’d never see, each about to do the same small piece of arithmetic she’d just done and reach the same answer and write it somewhere it couldn’t be unwritten. Call someone — she actually looked at the phone on the floor before she understood there was no one to call who could un-sign a signature that was already valid.

So she did the only thing left. She waited for the block.

She was unnerved by the silence.

“Siri, play songs by Rage Against the Machine.”

On the right monitor the two keys sat stacked and matched, unmoving. She didn’t want to look, but she did. She watched the left monitor, where Marcus’s harness showed a counter that read zero confirmations.

A block came on average in ten minutes. But average meant nothing tonight. It could be two minutes. It could be forty. Somewhere a machine was already building the next block, and the transaction carried a fee no miner would skip.

She’d picked the address because she could check it. Old, exposed, the public key sitting out in the open, untouched for twenty years — the one target she could prove instead of trust. The careful choice. The rigorous one.

“Dumb dumb dumb. Samantha, that was dumb.”

There was no quieter coin on Earth than one that hadn’t moved in twenty years. So many systems watched it. The dormant-wallet bots. The exchange desks. The chain-analysis shops that got paid to notice exactly this.

An address waking up after twenty years was the loudest thing that could happen on the chain. The careful choice and the loud one were the same. She hadn’t picked a quiet target. She’d picked the one guaranteed to be seen, and she’d picked it on purpose.

And then she’d trusted Marcus’s harness. That was the mistake.

She knew Marcus was sloppy. She knew she should have checked his work before she pointed it at a live key. She wanted to scream.

The counter still showed zero. She wasn’t clever - she was arrogant; she’d been so high on the breakthrough she hadn’t thought, hadn’t read the gray line of warning text, had just hit enter. She’d been impulsive. She was never impulsive. Almost never.

As Samantha stared at the screen, she tried to conjure up a scenario where this stayed small. A glitch. A test address. Nobody noticing. But she knew she was bullshitting herself. It was not small. Not a glitch. The most-watched event on the most-watched ledger anyone had ever built. Yeah, it wasn’t going to be small. At least her name wasn’t associated with it yet. Or at least she hoped it wasn’t.

The counter ticked to one.

One was all it took. A machine somewhere had folded her transaction into a block and the block onto the chain. One confirmation wasn’t final — a block could be orphaned, the chain could reorganize and cough her transaction back into the mempool. It changed nothing. The transaction was valid. Spit it out of one block and the next miner just picked it up again. There was no undo.

She sat with both feet flat on the floor, hands in her lap, afraid to move.

Fuck you, I won’t do what you tell me!
Fuck you, I won’t do what you tell me!
Motherfucker!
Uggh!

Vlad had been right about everything except the order of it. He’d always said that if it worked they wouldn’t get to choose what came next. He’d just assumed someone would take it from them. He hadn’t planned on her telegraphing it to everyone, by accident, in the first minute.

She picked the phone up off the floor. The screen was fine; of course it was fine.

“Siri, call Marcus.” She didn’t let herself think because nothing she could say sounded calm and sane. There was no value in waiting.

It rang once.

“Sam.” His voice was thick. “It’s three in the fucking —”

“It worked,” she said. “And it’s already gone.”

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