Roll auctions

Each week every Ditto Spot vault buys next week's LONG in a short auction. Makers sell it. The lowest ask wins, the vault pays in USDC, and the maker keeps the SHORT side of the pairs it minted.

The budget

When a roll starts, the vault has redeemed its LONG into USDC. The roll fee is set aside from that USDC; the rest is the budget. The auction runs for the window in Parameters.

An offer

You offer next week's LONG at an ask: a price in USDC per LONG.

• The ask must be above zero and at most the band's width.

• It must be strictly lower than the best ask so far.

• The offer escrows the whole quantity the budget buys at that ask:

  units = budget ÷ (next week's L + ask), rounded down

The vault keeps next week's L in USDC for every LONG it buys, so each LONG costs it L plus your ask. Escrowing the whole quantity means the best offer always fills the vault completely.

Where the LONG comes from

Mint pairs in next week's series: each pair gives you one LONG for the vault and one SHORT you keep. If the vault's budget buys 12 LONG at your ask, mint at least 12 pairs first. The app works out the shortfall and offers to mint it.

Winning and getting paid

After the window anyone can finalize. The vault pays the winner units × ask in USDC, takes the escrowed LONG, and pays the roll fee. If you escrowed more LONG than the vault bought, reclaim the rest from the same offer afterwards.

Being outbid

A lower ask replaces yours as the best offer. Cancel an outbid offer at any time to take back all of its LONG. The winning offer is locked until the roll finalizes, or until next week's series expires.

An auction without offers

If the window closes with no offer, holders can withdraw their USDC, and anyone can retry the auction with the vault's current USDC as the new budget, as long as a full window still fits before next week's expiry.