Murmur - Concept (Privacy/UX exploration)

Murmur has two sides, and they depend on each other. There is you, trying to disappear, and there is the crowd you disappear into. Your privacy is only as strong as the set of identical deposits around you, so the whole design is built to make that crowd legible and to keep you from a mistake you cannot take back.

The flow is simple on the surface. You deposit a fixed amount of tBTC into a shared pool and get a secret note. You wait while more identical deposits join behind yours. Later you paste the note, pick a fresh address, and withdraw. On the chain, no one can tell which deposit became which withdrawal. The interface stays quiet until you connect, then opens up to show your history and the live set.

This is concept work, not a shipped product. There were no users, no client, and no measured outcomes. The value is in the UX problem: making an invisible guarantee understandable while making irreversible actions feel deliberate.

On a public blockchain, every transfer is visible and traceable, by amount and by address. A privacy tool has to break that link. But the real design problem is not the math. It is trust and safety. The guarantee is invisible, so a person has to be shown, clearly, how hidden they actually are. And the steps are irreversible: lose your note and the funds are gone, paste a bad address and they are gone. The interface has to make the invisible legible and the irreversible deliberate, at the same time.

The concept has two sides: depositing into the crowd, then withdrawing from it without revealing which deposit was yours.

I tried two real directions for the amount step. One was a slider with snap points, the pattern most tools in this space use. The other was four discrete tiles. Both present the same fixed set, so the choice was about the mental model.

A slider implies a range you dial in, which fights the one idea the product depends on: amounts are fixed and identical. Tiles say it plainly, pick one of four equal buckets, and they give each amount room to show its own crowd size. I chose tiles. The slider is not wrong, it is a fine pattern. Tiles just make the interaction match the idea the privacy rests on.

Because nothing shipped, this is not a product before and after. It is the privacy state of a transaction. Before: a normal tBTC transfer is fully public, one traceable line from sender to recipient. After: many identical deposits go into a pool and identical amounts come out to fresh addresses, and the one true path is hidden inside the crowd. The crowd is the privacy.