Immutable composition
Every index begins with a precise onchain recipe: the assets it contains and the exact quantity of each asset that backs one share. Once created, that recipe cannot be edited, replaced, or rebalanced.
What becomes immutable
The index contract permanently records its underlying token addresses and the units required per share. No creator, administrator, or future token holder can add an asset, remove one, or change its quantity inside that index.
This makes the product legible. Anyone can inspect the same composition onchain and calculate exactly what must enter the vault when shares are minted and what must leave when they are redeemed.
Quantities stay fixed. Values do not.
Immutable composition does not mean fixed market value. If one underlying asset rises or falls in price, its share of the index's total value changes naturally. The contract does not trade assets to restore a target percentage.
For example, if one share is defined as 0.25 NVDA, 0.15 MSFT, and 0.02 ETH, those quantities remain the recipe even as their prices—and therefore their relative weights—move over time.
Minting follows the same recipe
To mint shares, a user supplies the full basket in direct proportion to the number of shares requested. Minting two shares requires twice the units recorded for one share. A partial basket cannot create a fully backed share.
Redemption reverses the process
Redeeming burns index shares and returns the corresponding underlying assets from that index's isolated vault. The same immutable quantities used for minting determine the redemption claim.
An asset may later be removed from the approved registry, which can stop new minting that uses it. That does not rewrite an existing index's composition; outstanding shares remain tied to their original backing and remain redeemable under the index rules.
Why this matters
Fixed composition removes discretionary portfolio management from the product. There is no manager deciding when to rotate assets, no governance vote changing what holders own, and no silent drift between the published basket and the contract's rules.
Immutability does not remove market, liquidity, token, network, or smart-contract risk. It makes one important part of that risk transparent: the assets and quantities represented by every share cannot change after deployment.
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