sat0, in one page

sat0 is a tiny on-chain protocol. it mints a token called sato by collecting eth along a fixed bonding curve, and lets you exit by burning sato back along the inverse curve. there is no order book, no liquidity provider, no admin, and no upgrade path.

the whole thing is two solidity files plus a small math library. once deployed, the parameters cannot change. nobody — including the deployer — can pause it, drain it, blocklist an address, or alter the formula. the contracts will keep behaving exactly as written until the chain itself stops running.

what this reference covers

this is the technical reference, not the gentle introduction. if you want the conceptual walkthrough, take the tour first. the pages here describe:

• architecturehow the v4 pool, the hook, and the token contract talk to each other.
• locked parametersevery constant the protocol leans on, why it exists, and where it lives.
• the bonding curveforward and inverse formulas, the marginal price, and how prb-math handles them.
• SatoTokenthe erc-20 itself: a locked minter, immutable genesis fingerprints, no admin powers.
• SatoHookthe v4 hook that hijacks every swap and replaces the amm with the curve.
• entropy windowthe first 100 blocks intentionally add ±10% randomness to mints.
• lifecyclegenesis → bootstrap → mature → exhaustion → dormancy, in chronological order.
• outcomeswhat the system makes possible and impossible, and what each rule actively prevents.
• reading the sourcewhere each piece of solidity lives and how to verify the deployed bytecode.

three numbers to remember

most of the protocol's behavior collapses to three constants. they are baked into the bytecode and identical for every participant:

• 21,000,000 sato— the supply asymptote. approached as more eth is added, never crossed.
• 500 eth— the curve scale. the eth amount at which roughly 63% of the asymptote (1 − 1/e) has been minted.
• 0.3%— the swap fee, charged on both buy and sell, accumulated inside the hook itself.

what this is not

• not a presale, not an ico, not a fundraiser.
• not upgradeable. there is no proxy, no admin, no migration.
• not a yield product. nothing in here pays you for holding sato.
• not advice. if you cannot read the source, do not put money near it.