Shared treasury

Accounts

The whole treasury is one account. Its address is derived from fixed seeds (a PDAProgram-derived address: an address worked out from fixed words and inputs, with no private key. Only the program can sign for it, so nobody can swap in a look-alike.), so the page can find it from owner one and the seed number, and nobody can swap in a look-alike.

Who can do what

• ActionWho signsRules the program enforces
• CreateOwner one, who also paysExactly three different, valid wallet addresses. The address must match owner one and the seed number.
• DepositAnyoneAn ordinary SOL transfer. Only a payment can take it out again.
• PayAny two different owners, in one transactionAmount above zero, the current nonce, before the deadline slot, to an address that is not the treasury, leaving the full rent reserve.
• Change ownersNobodyNo instruction exists to add, remove or rotate an owner.
• Pay alone, pause or closeNobodyNo single-owner withdrawal, no admin, no VEYDUCT control, no close instruction.

The owners you type at creation are permanent. Check every address before you approve: a wrong or lost owner can never be replaced.

A payment, step by step

The program checks one rule set for every payment. These are the exact checks, in the order it runs them:

1. Two different owners signedsigner one ≠ signer two, both in the owner listThe page names the second owner when you prepare; only that owner’s signature completes the transaction.
2. The nonce matchesrequest nonce = treasury nonceAfter a payment the nonce rises by one, so the same request can never run twice.
3. Before the deadlinecurrent slot < deadline slotAt the deadline slot itself the payment is already refused.
4. The reserve staysbalance − amount ≥ rent for 128 bytesOtherwise the whole transaction is undone and nothing moves.

Example (same numbers as Try it)

1. You create the treasury.0.01 + 0.00130048 + 0.000005 = 0.01130548 SOLVEYDUCT fee, the reserve that stays in the treasury, and the network fee.
2. You deposit 1.5 SOL.Spendable: 1.5 SOL. The 0.00130048 SOL reserve is on top and never spendable.
3. You prepare 0.4 SOL to a designer, deadline 250 slots, second owner B, and sign.1 of 2 signatures. Nothing moves.
4. B signs the same transaction and it is sent.network fee = 2 signatures × 5,000 lamports = 0.00001 SOLThe designer gets 0.4 SOL; spendable falls to 1.1 SOL; the nonce goes from 0 to 1.

Run the same steps in the Try it tab to see these numbers, and try sending with one signature or after the deadline.

Costs

VEYDUCT fee to create a treasuryPaid once by owner one, in the same transaction, to VEYDUCT’s fee wallet. Shown in the review.

0.01 SOL

Treasury rent reserve128 bytes at mainnet rent of 5,080 lamports per byte plus 128 bytes per account. It stays in the treasury.

0.00130048 SOL

Network fee to create or depositOne signature.

0.000005 SOL

Network fee for a paymentTwo owner signatures; owner one pays it.

0.00001 SOL

Percentage feesDeposits and payments carry no VEYDUCT fee, and the program takes no cut.

None

The program has no close instruction, so the reserveSolana keeps an account alive only while it holds a minimum balance for its size (rent). For the 128-byte treasury that is 0.00130048 SOL, and no payment can touch it. is never refunded; it is what keeps the treasury account alive.

Deadlines and timing

• Deadline: 1 to 10,000 slots. Solana makes a slotSolana’s clock tick. A slot passes about every 0.4 seconds (about 9,000 an hour). Deadlines on chain are slot numbers, not minutes. about every 0.4 seconds, so 10,000 slots is roughly an hour. Slots are not exact minutes.
• Blockhash: about 150 blocks. Both signatures go on one transaction with one recent blockhashA fingerprint of a recent block that every Solana transaction carries. The network accepts it for about 150 blocks (roughly a minute); after that the transaction can no longer land., which Solana accepts for roughly a minute. If it expires, both owners sign a fresh request.
• No proposals, queue or time lock. This is same-transaction co-signing: when two owners sign, it pays at once. For holder-approved payments with a waiting period, use Treasury voting.

Edge cases and what can go wrong

FAQ