IBTs and vault wrappers
How Stellar yield sources connect to Spectra Core v2.
An interest-bearing token (IBT) represents a position that can increase or decrease in underlying value. Stellar Core expects an IBT to expose a fungible-vault interface for deposits, redemptions, conversion previews, and exchange-rate accounting.
When a wrapper is needed
A compatible fungible vault can connect to Core directly. A wrapper is needed when the yield source does not expose transferable vault shares or does not implement the expected interface.
The Stellar implementation contains:
- An abstract Spectra Fungible Vault wrapper, which supplies common vault, access-control, pause, upgrade, and rewards behavior.
- A concrete Blend wrapper, which holds a Blend lending-pool position and issues transferable shares representing its bTokens.
Blend behavior
Blend bTokens are positions inside a pool rather than standalone SEP-41 token contracts. The wrapper therefore owns the pool position and represents it with its own transferable shares.
A wrapper is part of the backing trust boundary. A compatible interface does not prove that its exchange rate, liquidity, or accounting is safe.
See Integrating IBTs and wrappers for the contract expectations and review checklist.