How it works

A campaign moves through four steps: open, pledge, settle, claim. Every step is an instruction of the program and every money movement is between the campaign's own vault and a participant's own token account.

sequenceDiagram
  participant C as Creator
  participant V as Campaign vault
  participant B as Backer
  participant A as Anyone
  C->>V: create_campaign (bonus deposit moves in)
  B->>V: pledge (escrowed until the deadline)
  A->>V: settle (after the deadline)
  A->>B: claim_backer (failure: refund + bonus)
  A->>C: claim_creator (success: raised - fee + deposit)

1. Open

The creator calls create_campaign(id, goal, deadline, bonus_bps, bonus_deposit, uri). In the same transaction the whole bonus_deposit moves from the creator's token account into the campaign vault. No deposit, no campaign.

The program then fixes three numbers that nobody can change later:

• early_end = start + (deadline - start) / 2: the bonus window is the first half.
• early_cap = bonus_deposit x 10,000 / bonus_bps, rounded down: the most early pledging the deposit can pay the bonus rate on.
• early_cap <= goal, or the call fails with BonusAboveGoal. A failed campaign raised less than its goal, so bonus capacity above the goal could never be earned.

Example: a 1,000 USDC deposit at 20% gives an early cap of 5,000 USDC.

2. Pledge

A backer calls pledge(amount, min_eligible). The amount moves into the vault and stays there until the deadline. There is no withdraw instruction.

The part of the pledge that earns the bonus is:

pub fn eligible_part(now: i64, early_end: i64, amount: u64, early_cap: u64, early_pledged: u64) -> u64 {
    if now >= early_end {
        return 0;
    }
    amount.min(early_cap.saturating_sub(early_pledged))
}

So a pledge made at or after the halfway point earns nothing extra, and a pledge made early earns the bonus on whatever room is left under the cap. min_eligible lets the backer refuse to pledge if less than that would still earn the bonus when the transaction lands.

The backer's bonus is fixed at that moment: floor(eligible x bonus_bps / 10,000). Repeat pledges add to the same record.

3. Settle

Once now >= deadline, anyone may call settle. If total_pledged >= goal the campaign succeeded, otherwise it failed. On success the 2% fee moves to the fee vault for that mint, unless the creator locked the fee waiver.

4. Claim

Anyone may run the claims; the money only ever goes to the owner's own token account.

When every backer, the creator and any waiver are paid, close_campaign closes the vault and the campaign and returns the rent to the creator.

Worked example

Goal 10,000 USDC, 30 days, 20% bonus, 1,000 USDC deposit. You pledge 100 USDC on day 3.

• Goal met at 10,000 USDC: the creator receives 9,800 USDC plus the 1,000 USDC deposit back; 200 USDC of fee goes to the burn. You receive nothing back: your 100 USDC paid for the work.
• Goal missed: you receive 120 USDC (100 refund + 20 bonus).
• Had you pledged on day 16 instead, a miss would return exactly 100 USDC.