Solana · fee-fed buyback
It only rolls one way.
Every trade pays a fee. The fee buys the coin back and burns it in the same transaction. Nothing is sold, nothing is held, and the supply has no instruction for going up.
The whole machine. It fits on a card because there is not very much of it.
Every buy and every sell on pump.fun pays a creator fee in SOL. That stream is the only money that ever enters this system. Nothing is seeded, nothing is deposited, and there is no treasury sitting behind it.
A process claims the fee on every poll instead of batching it up. Claiming often costs close to nothing: on the launch this engine came from, the entire gas bill was 0.0025% of everything claimed.
The claim is divided into lots of 0.05 SOL and they go out one after another until the claim is gone. A bigger fee does not buy a bigger lot. It buys more of them.
Not bought and then burned. One transaction: the swap and the burn are instructions under the same signature, so either both happen or neither does. There is never a moment where the tokens sit anywhere they could be sold.
Read live. The market rows come straight from Dexscreener in your browser. The keeper rows come from the engine, and when it is not reachable they say so rather than guessing at it.
This is the part worth being pedantic about, because it is where this kind of machine usually breaks. A keeper that buys, and then burns a moment later, has a window. In that window the tokens are sitting in a wallet, and anything that can reach that wallet can move them first. A launch died exactly there: the tokens were bought, and they were gone before the burn fired. The chain showed a wallet holding zero and a supply that had never moved.
So there is no window here. The swap and the burn are instructions in the same transaction. It burns the guaranteed minimum the route promised, so the amount is fixed before the transaction is signed. If the burn cannot execute, the whole thing reverts and the SOL never leaves either.
buy + burn = one signature
Said here rather than left to be discovered. The fee is a share of the trading, so when the trading stops, this stops with it.
Quiet does not make the lots smaller. It makes them further apart. If there is not enough for a whole lot then there is no lot, and the remainder waits in the wallet for the next fee to join it. The most that can ever be sitting there unspent is one lot short of 0.05 SOL.
That is the difference between a machine that stops and a machine that starts pretending. When there is nothing to buy the count sits exactly where it was, and the page shows you it sitting there rather than filling the gap in.
The lot, the burn, the controller, and the things it deliberately does not do.
On pump.fun the token is a plain SPL mint. No transfer tax, no hooks, no clever transfer logic available to anybody. The one real lever is the creator fee stream: SOL off every trade, claimable on-chain by whoever created the coin. Everything here is built on that single lever and there is nothing else underneath it.
One buy is 0.05 SOL and the size never changes.
lots = claim / 0.05 (rounded down)
A fixed lot buys two things. The count becomes a real figure, because every entry in it is the same size. And the amount that can ever sit unspent is bounded in absolute terms rather than as a percentage: a rule that spends a fraction of what it holds leaves that same fraction behind on every cycle forever, which is why engines built that way need a sweep at the end to catch it. This one cannot leave more than one part-lot, so there is no sweep here at all, and a branch that does not exist is a branch that cannot be got wrong.
There is a cooldown between bursts and no wait at all between the lots inside one. That is the whole of it: a timer, a lot size, and a bound on how many lots a single burst may fire before the chain gets read again. No price is an input anywhere. Nothing escalates.
Worth stating plainly, because the opposite is the natural thing to assume. Fee income is volume, and volume peaks when the price does, so the money to buy with is most plentiful exactly when the coin is dearest. This is a buy-high machine by construction. On the launch this engine came from, the two largest buys were half of all the spending and they executed at the two highest prices. A fixed lot flattens that a little, because the size no longer swells with a hot market. It does not fix it, and nothing here claims to be clever about when.
Not the writing on this page. Every burn is a transaction with a signature on it, and the supply of the mint is a public number anybody can read without asking. If this page and the chain disagree, the chain is right. What you are trusting is that the process keeps running, and that is a person and a machine rather than a rule the network enforces. That distinction, and everything else that could go wrong, is set out in full on its own page.
Every claim, every lot, every burn, as the keeper recorded it. Click a signature through to Solscan and read it there instead of here.
no keeper wired yet
The mint, the wallet the fees land in, and every transaction it has ever sent.
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