the share token
The Etalon
An étalon is the physical standard a measurement is made against. Deposit into a Bar and you hold an ordinary ERC-20 — your wallet, a DEX and a lending market all handle it with no special support — whose redemption value rises as fees are harvested in.
What it is
An étalon is the physical object a measurement is made against — the metre bar in the vault at Sèvres, the gauge block on the bench. It is not the length; it is the thing the length is compared to.
Deposit into a Bar and you hold an ordinary ERC-20. Your wallet shows it. A DEX can
price it. A lending market can take it as collateral. Its redemption value is
totalAssets / totalSupply, computed by the contract from a number tracked in storage rather
than read from a balance — so a stray transfer into the vault changes nothing for you, and a donation
cannot reprice your position.
What it is not
It is not a claim on a fixed quantity of anything outside the vault. It is a claim on a share of what the vault holds, and what the vault holds is a tokenised equity — which is itself a claim on something that splits, pays dividends, halts, and trades for 19% of the clock.
Your balance is an integer in storage and does not move unless you move it. Everything underneath it moves without asking. That is not a flaw in this design; it is the situation, and the only unusual thing here is that the contract writes down when each reading was taken so the two can be told apart.
Eighteen decimals for a thing that has one
Every tokenised equity on this chain has 18 decimals. A share of stock is an integer in the DTC; you cannot own a third of one there. The divisibility is real on chain and is a property of the token rather than of the security it names, and the difference is the same difference this whole site is about.
Price, from the contract
convertToAssets(shares) reads two storage slots and
divides. There is no oracle in this path, no feed, and nothing that can be stale, because nothing is
being observed — the number is an accounting fact about the vault.
And a block beside it
Every deposit, redemption and harvest appends a Fringe: the block, the timestamp, and the pair. One row per block, and it is the state at the end of that block. P16 to P18 are that guarantee.
A million virtual shares
The offset against the first-depositor attack is
1e6, and it is that large because the property suite ran the attack: at
1e3 the victim came out 0.45% short. Every property still held. Only executing it found
the gap.