Opera RK · A new standard for listening

A record you
hold once.
Then it’s ash.

CFT — the Consumable File Token. Music bound to a physical object and a self-destructing key. You may listen one time. After that, the recording is gone forever — and all that remains is the object in your hand and the proof that you were there.

Experience the burn →Read the standard
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The problem

Streaming made music infinite, and therefore weightless.

When everything is available, always, for almost nothing, the act of listening loses its edges. Songs become wallpaper. We skip before the second chorus. The price of a play spiralled to zero — and so did our attention.

CFT asks a heretical question: what if a recording could be scarce again? Not the ownership of a file — the experience of hearing it.

A commuter listening, lost in the blur of infinite music
Infinite access · zero weight
≈ $0.003
paid to artists per stream
∞
replays of every track, forever
1
listens a CFT will ever allow

Feel it

Press play, and you spend it.

One copy. One listen. No undo.

A demonstration, not the real thing — but it is exactly how a CFT behaves. Once consumed, the decryption key is destroyed and the recording can never be played again. What remains is the object you hold and the proof, on-chain, that you were there.

The life of a CFT

Four states. One of them is permanent.

A CFT moves through a one-way lifecycle written into the standard. You can trade it, hold it, gift it — but you can only ever cross the final threshold once.

01 / minted
Sealed

The music is encrypted and bound to a physical object. It has never been heard. It is yours to keep, trade, or gift.

02 / market
Carried

While sealed, it changes hands freely on the open market. The artist earns a royalty every time it does. The tension grows: listen, or pass it on?

03 / the once
Consumed

You decide to listen. A single decryption is authorised. The music plays — start to finish, unpausable, unrepeatable.

04 / forever
Ash

The key is destroyed; the recording can never play again. The token lives on as proof you heard it — a relic you can still hold and trade.

The CFT physical object

A thing you can hold

Not a link. An object.

Every CFT is embodied in a physical artefact — a chip, a pressing, an object Philipp and Opera RK design as carefully as the music. A tamper-resistant secure element inside it holds a key that can never be copied out.

  • ◷
    Physically backed
    The object is the key. Built on the Physical Backed Token model — the chip cryptographically proves authenticity, with no middleman.
  • ⊘
    Non-extractable
    The private key is generated and sealed inside the secure element. It signs, but it never leaves.
  • ✶
    The ritual of the tap
    To listen, you bring the object to your player. Presence is required. Listening becomes an act again.
Philipp Zürcher in his studio, at the pedal steel guitar
★ Artist Zero

The first listen belongs to one musician

Philipp Zürcher

A Swiss musician releasing the first work ever issued as a CFT. Not a single, not an album — a piece of music engineered to be heard once, by one person at a time, and then to pass into memory.

“I want you to be unable to take it for granted. To know, while it plays, that it is leaving.”

Follow the first drop →

The standard · CFT v1.0 draft

We didn’t invent the cryptography. We composed it — and added the one missing piece.

A deep prior-art review confirmed it: no existing token standard destroys itself after a single use. CFT stands on proven building blocks and contributes the genuinely new layer — a consume-once, self-destructing key. It is being written as an open, formal EVM standard. Free for any artist to use.

ERC-721
Ownership & trade
A CFT is a real, tradeable token. Buy it, sell it, gift it — while it’s still sealed.
ERC-2981
Artist royalties
The creator earns automatically on every resale, forever — written into the token.
ERC-5791
Physically backed
Binds the token to the chip in the object via a non-extractable key. The object is the proof.
ERC-2135
Consume on listen
The on-chain act of consumption — the moment the work is spent, recorded for all time.
threshold
Conditional decryption
The audio is released only when the single listen is authorised — guarded by a decentralised key network.
★ CFT
The consume-once key
The new contribution: a key satisfiable at most once, then destroyed. The recording becomes unrecoverable. This is what no one had built.
Read the full spec on GitHub →

A lineage, not a gimmick

Art has always flirted with disappearance.

CFT extends a recognised artistic tradition — scarcity and impermanence as the work itself — into sound, and onto the chain.

1998
DIVX
A pay-per-window disc — the first mass attempt at play-limited physical media.
2003
Flexplay
A DVD chemically engineered to self-destruct hours after the seal was broken.
2015
Wu-Tang · Shaolin
A single physical copy of an album, sold as a unique art object. The defining precedent.
2026
CFT
The first to make self-destructing, play-limited, tradeable scarcity a reusable standard — for any artist.

Join the debate

How should we
listen now?

CFT is a provocation as much as a product — a question about attention, value, and what we owe the music we love. Be there for the first listen, and help shape the standard.

Hard questions, honest answers

You’re sceptical. Good.

In the Best-Effort profile, yes — in principle, as with any sound that reaches a speaker. But that misses the point. CFT is not unbreakable DRM; it is a cultural contract, like Wu-Tang’s single-copy album. The value lives in honouring the once. For collectors who want a hard guarantee, the Hardware-Enforced profile decrypts and plays inside a secure element on the object itself, so the file is never exposed in the clear.
Then you’ve lost your listen — exactly as you would lose a one-of-a-kind pressing. The object is the key. That fragility is deliberate: it’s what makes holding one feel like holding something alive.
Yes. On consumption the decryption key share is destroyed and the ciphertext becomes permanently unrecoverable. The token itself persists on-chain as an ‘ash’ — a provable, tradeable record that this work was heard, once, by you.
An NFT proves you own a file you can replay forever. A CFT makes the act of listening itself scarce. No existing token standard destroys itself after a single use — that is precisely the gap CFT fills. It composes the proven parts of the NFT stack (ERC-721 ownership, ERC-2981 royalties, physically-backed binding) and adds the one missing piece: a consume-once, self-destructing key.
For the same reason people buy a ticket to a concert that ends, a meal at a great restaurant, or a single-copy artwork: the most precious experiences are the ones that don’t repeat. CFT turns a recording into an event — and an heirloom you can pass on, unheard, or choose to spend.
Yes. While sealed, a CFT is freely tradeable, and the artist earns a royalty on every resale. The tension — listen now, or hold it, or pass it on still sealed — is the whole drama of owning one.
CFT targets a low-energy proof-of-stake EVM Layer-2, where a transaction’s footprint is negligible. The standard is chain-flexible; energy cost is a design criterion, not an afterthought.