Read the
instrument.
Vellum turns an ERC-20 balance into a bearer note: a transferable ERC-721 that carries the deposited amount and a chosen term, and that its current holder can redeem at any time.
What is Vellum
#Vellum is a small, non-upgradeable vault protocol. You deposit an exact ERC-20 balance into the VellumVault contract and receive one ERC-721 token — a note. The note is the claim on that balance. Whoever holds the note can transfer it like any other NFT, and whoever holds it at the moment of redemption receives the underlying tokens.
Nothing else happens to the deposit. There are no fees, no yield strategies, no admin withdrawal path and no way to change a note after it is minted. The vault records the token, the amount and a term (a reference maturity date), then waits for the holder to claim.
The term is metadata, not a lock. A note minted with a 90-day term is claimable in the same block it is minted. The term describes the horizon the depositor chose; it never delays redemption.
In one minute
#Wrap
Approve the vault for an ERC-20 amount and call wrap(token, amount, termSeconds). The vault verifies it received exactly that amount and mints note #tokenId to you.
Carry
Hold the note or move it with transferFrom / safeTransferFrom. The tokens never leave the vault during a transfer; only the claim changes hands.
Claim
The current holder calls claim(tokenId). The note is burned and the full underlying balance is sent to the caller. A note can be claimed exactly once.
Everything the note represents is readable from the contract: positions(tokenId) returns the token, amount, maturity and claimed flag; ownerOf(tokenId) returns the current claimant; isClaimable(tokenId) tells you whether the note is still live.
Who this is for
#- Holders who want to move a position between wallets — or sell it OTC — without unwinding the underlying balance. Start with Using the app.
- Counterparties who need to verify what a note actually contains before accepting it. Start with Core concepts and the contract reference.
- Integrators building gates, collateral logic or allocation tooling on top of notes. Start with the developer guide.
- Reviewers auditing the guarantees. Start with the security model.
Documentation map
#Positions, notes, terms, claimability and the guardian role.
02Note lifecycleWrap, carry, transfer and claim — with the events each step emits.
03Contract referenceEvery function, event, constant and revert reason of VellumVault.
04Networks & tokensSupported chains, listed tokens and how the vault address is resolved.
05Using the appConnect a wallet, wrap a position, claim a note, configure the CA.
06Security modelGuarantees, assumptions, known limits and what the guardian cannot do.
07Developer guideLocal setup, scripts, environment variables, deploy and integration.
08FAQShort answers to the questions people ask before the first note.