Spending conditions

Plain Cashu proofs are bearer tokens: anyone who has them can spend them. Spending conditions lock a proof so it can only be spent with extra knowledge.

NUT-10 is the generic envelope. NUT-11 is pay-to-public-key (P2PK). NUT-14 is hashed timelock contracts (HTLCs), useful for atomic swaps. NUT-28, pay-to-blinded-key (P2BK), blinds the P2PK receiver key so the mint cannot link multiple locks to the same person.

In this chapter

• NUT-10 — Spending conditions
• NUT-11 — Pay-to-public-key (P2PK)
• NUT-14 — Hashed timelock contracts (HTLCs)
• NUT-28 — Pay to blinded key (P2BK)