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BasketBasket Docs

Composition changes

A fixed-weight basket’s tokens and target weights can change over time. A token can be added or removed, or the weights adjusted. Every change is announced on-chain and can’t take effect for three days. This gives holders who don’t want the new mix time to redeem first.

Fixed-units baskets can’t change their composition.

The timeline

Section titled “The timeline”
  1. Proposed. The basket’s authority proposes the new set of weights. Only one change can be pending per basket. The app shows a banner on the basket’s page with the change and when it takes effect.
  2. Notice period: 3 days. The change can’t be applied before then.
  3. Apply window: 7 days. After the notice period, the change can be applied within seven days. If it isn’t, it lapses and has to be proposed again.
  4. Rebalance. Applying a change sets the new targets. Added tokens start empty, so the basket is immediately due for a rebalance that moves it to the new weights.

The authority can cancel a pending change at any time.

  • Day 0. The authority proposes new weights: trim A and C, add a new token D. The app shows the change on the basket's page.
  • Notice. For three days nothing changes. Holders who don't want the new mix can redeem.
  • Applied. Within the next seven days the change is applied and the targets switch. D starts empty.
  • Rebalance. The keeper trades the holdings into the new weights.

Protections for holders

Section titled “Protections for holders”
  • Exits stay open. Nobody can pause redeems, so holders who don’t want the new mix can always redeem during the notice.
  • No fee hike behind the change. A change can’t be applied if the basket’s total redeem fee is higher than when the change was proposed. Changing the redeem fee also restarts the notice.
  • No surprises mid-operation. A change applies only when no mints, redeems or rebalances are in progress.

Limits on a change

Section titled “Limits on a change”
  • A change can add at most 10 tokens, and the basket can’t exceed 20 tokens in total.
  • Every token kept or added needs a weight of at least 0.5%. To remove a token, give it a weight of 0.
  • The weights must sum to 100%, and the change has to actually change something.
  • The USDC slot’s weight can’t change. Tokens added by a change must be classic SPL tokens.