An NFT series created to change Bitcoin

Catch up quick: The team behind one of the first hot NFT collections, Taproot Wizards, created a collection called Quantum Cats as a way of dramatizing support for reinstating a bit of code on Bitcoin.

• The code was called "operation concatenate" or "op_cat," in the code base, and it was disabled long ago by Bitcoin's creator because he believed it could be used in denial-of-service attacks.

There's a proposal in the Bitcoin Github to turn op_cat back on. That proposal followed a discussion on the Bitcoin developers mailing list that started in October.

Quantum Cats want op_cat to create a permissionless bridge to take bitcoins and bitcoin assets (such as the cats) onto Bitcoin layer 2 chains — layers built on top of Bitcoin — where they can engage in more complex trading.

• They call it CatVM (or Cat Virtual Machine). It needs op_cat to work.
• Bridges have allowed a lot of losses in the blockchain world, but the Taproot Wizards folks believe op_cat opens up a path to bridge more safely and simply.

Zoom in: Quantum Cats are Bitcoin NFTs that change over time.

• Most Bitcoin NFTs refer to one piece of artwork inscribed on the Bitcoin blockchain. Each Quantum Cat actually refers to several files, not all of which have been revealed yet.
• As new files get revealed, the cats change. In other words: they are putting data together (concatenating).

Between the lines: That's how they reflect what op_cat would do, if it were turned back on.

• The code allows two pieces of information to be put together at the same time, which allows all kinds of new functions.
• A simple one to understand, though, might be the idea of "vaults" that could have certain kinds of rules.

For example, someone with a lot of bitcoin might set a rule that only small transactions can be allowed from a vault (like, 0.1 BTC, once per day).

• That way, if someone got hold of their private key, they wouldn't be able to steal that much (additional rules could allow the rightful owner to move their coins out of a compromised vault).

The latest: Yesterday, Udi Wertheimer, a jokester in the Bitcoin world and a co-founder of Taproot Wizards, tweeted that the op_cat proposal had received a Bitcoin Improvement Proposal (BIP) number, which would be a first step on the way to implementation.

• In fact, he said it would be BIP-420 (which was a hint).
• Reality check: It had not. It doesn't show up on on the official BIP list.

Yes, but: The Bitcoin developers are actively discussing adding new editors to the Bitcoin Github, which — If and when new editors get onboarded —should mean proposals would move along more quickly.

Context: The last notable change for Bitcoin was implemented in 2021.

What we're watching: If op_cat really does get improvement proposal status, it will be a sign that NFTs have another use case: blockchain advocacy.