What this costs
Hazync proves Bitcoin's chain so that a new node can check it instead of trusting it. That is rented GPU time and a handful of servers. The bills have been paid by one person; a good deal of the proving has been done by contributors running their own cards, for nothing. Every figure below is measured from a bill, not estimated.
Keeping the lights on
£415 a month, before a single new block is proved.
£415 a month is £4,978 a year, and the GPU is two thirds of it — more than every server put together. Domains add another £0.75 a month. Servers billed in euros, the rest in dollars; converted at the rate Hazync's own payment server quoted on 26 September 2026, £1 = €1.163 = $1.325.
What a proof actually costs
Between 9p and £4.45 a block, depending where in the chain it sits.
A proof is made on rented GPUs, and the price is set by how much work the block contains. An early block from 2011 holds a handful of transactions. A block at the current tip can hold several thousand, and costs fifty times as much to prove.
| An early-chain block | £0.09 |
|---|---|
| Block 966,256 — 9,079 inputs, 27 cards, 9 minutes | £1.05 |
| Block 968,340 — 9,600 segments, 15 cards, 32 minutes | £4.45 |
| An hour following the chain's tip, 15 cards | £8.33 |
| September 2026, spent on GPUs | £556 |
The rows above are what a proof costs when a run goes right. The total is what was actually spent, and the two do not reconcile — the difference is runs that failed, fleets rented that never started, blocks proved twice, and mistakes. That is what building this has cost, and it is the honest number. September was a month of getting the tip proving working at all, so it is not a monthly rate. The cost of proving the whole chain is not yet measured, and we would rather say so than guess at it.
Three ways to pay for it
Pick whichever fits what you want to happen.
Sponsor a block
Name a block and pay for its proof. You get the receipt, and the block carries your handle on the board for good. This is the most direct thing you can buy: a specific piece of Bitcoin's history, proved and checkable by anyone, because you paid for it.
Donate
No block in mind — just keep it running. Donations go to the servers first and the proving after. Pay what you like: the checkout takes bitcoin on-chain or over Lightning, and you choose the amount.
Payments run on our own BTCPay Server. Nothing is custodial and no processor sits in between. Any address claiming to be Hazync's that did not come from that button is not ours. Every donation received is listed here, published automatically by the job that watches for payments.
Partner
If you want the capability to exist — a client that syncs from a proof rather than from trust — the useful thing is not a donation but a standing commitment: GPUs for a long stretch of chain, or a card kept on the tip. That is a conversation, not a button.
Where this stands
The part most projects leave out.
Hazync is not a company and has no runway. Every invoice so far has come out of one person's pocket, and that is not something that continues indefinitely.
That is not the whole story, and it would be wrong to let it stand as one. A large share of the chain has been proved by people who pointed their own GPUs at it and asked for nothing — electricity they paid for, on hardware they own. They are the reason there is anything here to fund. What money buys is the part they cannot donate: the servers that hand out the work and keep the record, and the card that never stops folding what they produce into a single proof.
The work is real. Blocks at the chain's tip have been proved and independently verified, and the genesis-anchored proof is checked against Bitcoin's own cumulative work every ten minutes. But the bill arrives monthly regardless.
£415 a month keeps what already exists alive: the proof stays anchored, the folding keeps up, and the record stays in two places that are not us. Anything beyond that buys proved chain, at the prices above. Anything short of it comes out of a pocket that is not bottomless.