Developers

Program reference

Instructions, accounts and the checks each one makes.

Chord’s settlement program is written with Anchor 0.31.1 and supports the classic SPL Token program only. Its source is the authoritative contract; this page summarizes it.

#Instructions

Instruction	Signed by	What it does
`initialize`	Upgrade authority	Creates the one immutable config: auctioneer, treasury, chain domain, bond size
`register_solver`	Solver	Creates the solver account with a bond of at least the config’s size, if the solver’s CHORD stake meets the minimum
`top_up_solver`	Solver	Adds lamports to the bond
`withdraw_solver`	Solver	Withdraws unlocked bond
`create_batch`	Auctioneer	Opens a batch for an enabled market, with that market’s slot windows and order cap
`commit_batch`	Auctioneer and solver	Writes the price and budgets, escrows reserves, locks a bond; the solver’s stake must meet the minimum
`settle_fill`	Auctioneer, after the owner’s Ed25519 verification	Fills one signed order against the committed price
`finalize_batch`	Anyone	Completes a fully filled batch; unlocks the bond, refunds reserves
`timeout_batch`	Anyone	After the deadline with budget unfilled; slashes the bond, burns 10% of the solver’s stake, refunds reserves
`expire_uncommitted`	Anyone	After the deadline, closes a batch that never committed
`claim_refund`	Anyone	Retries a reserve refund once frozen accounts thaw
`cancel_nonce`	Order owner	Writes a cancelled receipt for one nonce
`advance_nonce`	Order owner	Raises the owner’s nonce floor
`initialize_staking`	Upgrade authority	Creates the stake pool for a CHORD mint with no mint or freeze authority
`set_stake_authority`	Pool authority	Hands parameter changes to a governance of the pool’s realm; any other account is refused
`set_stake_timing`	Pool authority	Sets the unstaking cooldown and the vote window, each 1 to 365 days
`set_min_solver_stake`	Pool authority	Sets the minimum stake to register and commit
`set_market`	Pool authority	Lists, retimes or pauses a pair: windows, order cap, enabled
`stake`	Staker	Moves CHORD into the staking vault
`unstake`	Staker	Starts the cooldown; refused while the staker’s solver has a batch open
`withdraw_stake`	Staker	Returns cooled-down CHORD
`update_voter_weight_record`	Anyone	Writes a staker’s voting weight for one governance action, valid for one slot

#Phases

Slots strictly increase through a batch: creation, then collection end, then solve end, then the settlement deadline. Quotes compete between collection end and solve end. Commit is allowed from solve end to the deadline, fills until the deadline, and timeout or expiry strictly after it.

#Errors

Error	Meaning
`InvalidParameter`	A zero or out-of-range value
`Unauthorized`	The signer isn’t allowed to do this
`InsufficientBond`	Not enough unlocked bond
`InvalidWindow`	Batch slots don’t strictly increase, or don’t match the market’s windows
`InvalidPair`	Tokens don’t match the batch pair
`WrongPhase`	Not allowed in the batch’s current phase
`InsufficientReserve`	Reserves don’t cover every gross output
`Expired`	The order’s expiry slot has passed
`IntentMismatch`	An account or the signed message doesn’t match the order
`TokenOwner`	Source or destination isn’t the owner’s
`DelegationRevoked`	The allowance was revoked or is too small
`NonceInvalidated`	The nonce is below the owner’s floor
`Cancelled`	The nonce was cancelled
`NonceAlreadyUsed`	The nonce is bound to another order or batch
`Overfill`	The fill exceeds the signed sell amount
`PartialForbidden`	A partial fill of an order that doesn’t allow one
`LimitPrice`	The rounded output misses the signed minimum
`BudgetExceeded`	The fill exceeds the committed budget
`UnfilledBudget`	Finalize was called before both budgets filled
`MathOverflow`	Checked arithmetic failed
`SignatureInstruction`	The Ed25519 verification before the fill isn’t the one canonical layout
`StaleFill`	The receipt changed since the fill was prepared
`MarketDisabled`	The pair has no enabled market
`OrderCap`	The batch already filled its market’s order cap
`StakeTooLow`	The solver’s stake is below the minimum
`StakeLocked`	The solver has a committed batch that isn’t finished
`CooldownActive`	Unstaked CHORD is still cooling down
`NothingToWithdraw`	No cooled-down CHORD to withdraw
`InvalidProposal`	The vote target isn’t a proposal voting with CHORD
`MintAuthority`	The staked mint can still mint
`VoteWindowClosed`	The vote comes after the pool’s vote window for that proposal

#Arithmetic

All products are computed in u128 and checked back into u64. Outputs round down; minimums and reserves round up. Every rounding choice favours the trader’s limit or the escrow’s sufficiency, never the solver’s margin.

#Upgrade authority

The program is upgradeable, and its upgrade authority is a trust assumption like any upgradeable Solana program. The config is not: once initialized, its auctioneer, treasury, chain domain and bond size can’t change.

#Governance plugin

The program is the realm’s voter weight plugin on spl-governance. update_voter_weight_record writes a VoterWeightRecord for one action and target, expiring in the same slot, so it goes in the same transaction as the vote or proposal it serves. For a vote, the weight is the staker’s active stake less every deposit made in or after the proposal’s voting slot; for anything else, it is the active stake. CHORD in its cooldown never counts.