Technically speaking, Chaumian ecash is non-custodial at the cryptographic layer — you hold the tokens, the mint never sees your balances, and it cannot move or seize your ecash directly. Blind signatures are genuinely clever.

Here's the catch: most ecash mints today are backed by a reserve asset — usually bitcoin — which is held by the mint. The mint controls that bitcoin. If the mint rugs, gets hacked, or simply disappears, your ecash becomes worthless. The underlying collateral is fully custodial.

So: custodial bitcoin wrapped in a non-custodial protocol. Cashu is a genuinely elegant system — just know that using it means trusting a mint with your bitcoin. Understand the risk, use it accordingly.

tl;dr — trust the math, not the mint