Incentive streams

On top of organic yield, a vault can carry an incentive stream: a pool of the vault’s own coin that vests into the share price gradually over a set period. It is a way to boost returns smoothly rather than as a one-off jump.

How it vests

An incentive of total over a duration from start to end releases linearly with time. At any moment now, the amount that should have vested so far is:

$$\text{released}(\text{now}) = \begin{cases} 0 & \text{now} \le \text{start} \\[4pt] \text{total} \cdot \dfrac{\text{now} - \text{start}}{\text{end} - \text{start}} & \text{start} < \text{now} < \text{end} \\[4pt] \text{total} & \text{now} \ge \text{end} \end{cases}$$

Whenever the vault is poked (every deposit, withdrawal, or rebalance), the newly-vested slice since the last update is folded into the pool as earnings, lifting the share price for everyone, exactly like organic yield.

Important properties

• It is not your principal. The unvested reserve is held off the books, it is not part of total_coin_in, so it is not withdrawable as if it were pool value. Only the portion that has actually vested counts toward the share price.
• No performance fee. Incentive vesting is compounded with no performance fee taken, the full amount reaches holders.
• Smooth, not lumpy. Because it vests continuously, the share price rises steadily over the stream’s lifetime rather than spiking when funded.

Note

You don’t need to do anything to receive incentive yield, it accrues into the share price automatically as the vault is used. Holding samSUI / samUSDC is enough.