Without OP_CAT, Bruce Liu says Bitcoin is as “useful as a jumbo -jet without wings” that is capable of much more than is allowed to do, but is stuck on the ground while Ethereum and Solana are hovering.
Liu, the founder of OPCAT_LABS, says a single OPCODE, OP_CAT, could transform Bitcoin from static digital gold into programmable money competing with other LAG-1 chains.
OP_CAT is a long-handicapped OPCODE in Bitcoin’s code which, if enabled, would allow developers to link data into scripts and lock a number of new options, from vaults and covenants to decentralized exchanges and zero-knowledge proof.
Bitcoin Blockchain, if OP_CAT was activated, would be as programmable as Ethereum or Solana, Liu said.
“Up_cat is not a new code. It was never deleted, just commented and disabled. We are not adding my OPCODE or someone else’s. It’s Satoshis,” Liu told Coindesk during an interview on the sidelines for BTC Asia in Hong Kong.
But pushed to OP_CAT does not come without friction.
Satoshi disabled it in 2010 over concern that it could enable attacks from the denial of service. Opponents claim that any new opcode introduces “unknown unknowns” that threaten Bitcoin’s hard -won stability. Others take a philosophical attitude: Bitcoin should remain digital gold instead of chasing Ethereum’s programmability.
Liu pushes back by appealing to Satoshi Nakamoto’s design.
“If Bitcoin was only for payments, why did Satoshi include Script at all?” He asked. “Up_cat is not my invention, it is Satoshi’s code. It was never deleted, only disabled.”
Liu says OP_CAT would bring script to life – the basic programming language built into Bitcoin blockchain – giving Bitcoin the opportunity to make more than just payments and enable features such as vaults or even basic defi.
OP_CAT, he said, would unlock more of this potential and let developers build things like vaults, covenants or even simple defi apps on Bitcoin.
To reinforce the point, he points back to Nakamoto’s own explanation of why manuscript existed in the first place.
In a Bitcointalk post in 2010, Nakamoto wrote that Bitcoin’s design was effectively “set in stone” from his first release, so he wanted it to accommodate any type of transaction he could imagine.
Hard-coding each one would have created endless special cases, Satoshi explained, so instead introduced the Bitcoin creator instead of getting users to check if the nodes should only check if these conditions were met.
Already, the company launched a fork of Bitcoin in a virtual machine with OP_CAT enabled to demonstrate its potential, complete with SDKs, APIs and a Javascript-like programming language designed to make building on Bitcoin available to web2 developers.
OP_CAT -LOBBY
The other half of Lius plan is political. Alongside Mate Tokay, an early Bitcoin entrepreneur who co-founded Bitcoin.com with Roger Ver, OPCAT_LABS is at the head of what they describe as an “alliance” of OP_CAT supporters.
The goal is to coordinate otherwise scattered efforts from groups such as Taproot Wizards, Starware and Independent Developers.
“Previously, OP_CAT was leading,” Liu said. “Ninety percent of the people we are talking to are for, but the highest voices are the ones that are against. We want to organize support for something visible, semi-official and coordinated.”
Tokay frames it as an education campaign for influential stakeholders, fund managers, institutions and even legislators, as he says is too focused on BTC state boxes to note the programmability debate.
“If they knew what up_cat unlock, they would be even more excited about Bitcoin’s future,” he said.
At next year’s Bitcoin Asia conference, Liu hopes to show work -defi -apps on Bitcoin and move on to an organized lobbying business.
He frames it as a locking potential that has been there all the time. “We don’t change Bitcoin,” he said. “We unfold wings.”
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