NOPE CAT Merch
Show your support with NOPE CAT merch. Sold at cost.
Keep Bitcoin Simple. Keep Bitcoin Money.
OP_CAT enables stateful contracts and generalized computation, introducing n‑th order effects and complexities that are impossible to fully predict & analyze.
By enabling AMMs, lending, farming and other DeFi gambling schemes, OP_CAT would bring to Bitcoin the same speculative chaos that has plagued Ethereum.
Miner Extractable Value dynamics threaten to distort Bitcoin's carefully balanced incentive model—a problem largely considered unsolvable on other networks.
State-rich smart contracts balloon both blockchain size and mempool churn, making it more expensive to run full nodes and weakening the network's decentralization.
Speculative high-value DeFi activity could dominate block space, driving up fees and pricing out everyday users that simply want to store and transfer value.
OP_CAT's cryptofication of Bitcoin serves token issuers and crypto gamblers, not Bitcoin's core users using it for its core purpose—a neutral, robust, globally accessible money.
Bitcoin isn't here to do everything. It's here to do one thing right: be a self-sovereign, neutral, sound money for the world. Over the years, Bitcoin resisted the urge to turn into an experimental playground that caters to every use-case and remained focused on its core mission. The proposed introduction of OP_CAT undermines these principles by opening the door to complex, stateful contracts and generalized computation that Bitcoin was not designed to handle.
OP_CAT isn't just another opcode. By expanding Bitcoin's scripting capabilities, it removes key constraints that have kept complex speculative contracts off-chain—paving the way for a DeFi frenzy of AMMs, consensus-enforced tokens, yield farming, staking, and other on-chain gambling schemes. This would turn Bitcoin's block space into a battleground for speculative Ethereum-style applications that crowd out everyday monetary use. Because high-risk traders chasing big returns are largely indifferent to fees, they could dominate block space, driving up fees and pricing out users who simply want to store and transfer value.
The harmful impact goes beyond prohibitive fees. State-rich DeFi apps balloon both blockchain size and mempool churn, due to their use of high-frequency Replace-by-Fee interactions and the botting activity they invite. The inflated operational costs for full nodes and the introduction of MEV mechanics further threaten to distort Bitcoin's carefully balanced incentive model.
Rejecting OP_CAT isn't about resisting all protocol changes; it's about favoring cautious, well-audited proposals that improve Bitcoin without introducing unknown complexities or fueling speculative frenzies at the base layer. For example, OP_CTV (BIP 119) offers clear, predictable benefits—such as enhanced self-custody, inheritance planning and payment pools—without inviting the risks, unpredictable consequences and bloat that OP_CAT would.
Bitcoin remains the best form of money because of its disciplined minimalism and resistance to mission creep. It's flexible enough to support sophisticated self-custody mechanisms and L2s, yet constrained enough to prevent Bitcoin from turning into a DeFi playground. By rejecting OP_CAT, we preserve Bitcoin's primary mission—serving as sound money that is accessible to all. Let's keep Bitcoin simple, predictable and true to its core purpose.
Help protect what makes Bitcoin great. Spread the word, take a stand and push back against reckless change.
Show your support with NOPE CAT merch. Sold at cost.
While it may appear simple, its impact is anything but. OP_CAT significantly expands Bitcoin's scripting capabilities, enabling an entirely new class of contract functionality and introducing new, unpredictable dynamics that could disrupt the network's economics and incentives.
Activating OP_CAT would be by far the biggest change ever made in Bitcoin's history, with the most far-reaching consequences. An irreversible change of this magnitude demands serious scrutiny, not casual dismissal as "just a simple opcode."
While speculative DeFi activity can generate fee revenue for miners, it can also cause sudden surges in network congestion, high fees for everyday users, and the risk of MEV. Fee spikes from speculative booms tend to be highly cyclical, leading to wild fee volatility. In contrast, a stable fee market that grows organically from real monetary use is more predictable and less prone to frenzy-induced congestion.
Bitcoin's long-term viability lies in steady, organic fee growth that reflects genuine monetary usage, not fleeting speculation.
Rather than prematurely worrying about the mining security budget, we should use the time afforded by the block reward subsidy to make self-custody more accessible to the masses. If block space demand doesn't grow sufficiently, there will be plenty of time—probably at least 2-3 more halvings—to consider alternative non-money uses for Bitcoin's base layer. But rushing into irreversible protocol changes this early would be an overreaction that undermines Bitcoin's goals.
It is also very likely that, in the coming years, we'll actually face the opposite challenge of extreme congestion and high fees, and that the Bitcoin development community will have to dedicate significant effort and creativity to scaling Bitcoin so it can keep up with humanity's growing demands—even if it remains focused solely on being money and unburdened by DeFi bloat.
And frankly, the "Bitcoin isn't used enough as money, so let's at least use it for something else" attitude feels defeatist. That's like Apple launching the iPhone to revolutionize global communications, hitting a few slow sales quarters, then go like: "Well, we can at least sell them as paperweights."
Slow and steady wins the race. There's no need to rush. Bitcoin plays the long game and rejects the high-time preference mindset.
Not at all. While some well-funded groups are aggressively pushing OP_CAT, it remains highly controversial within the Bitcoin community, with no agreement on its necessity or safety.
Bitcoin development is rigorous, consensus-driven process that requires careful review and widespread support. Flashy promotions and corporate-funded lobbying can't replace the hard work of proving a change is necessary, safe, and in Bitcoin's long-term interest.
Bitcoin's value proposition lies in stability and resilience, not in chasing shiny new features. Innovations can and do happen—just at a measured pace. Changes to the base layer must be carefully considered, ensuring they advance Bitcoin's goals without introducing unnecessary risk. This disciplined approach has kept Bitcoin the most secure and robust monetary system in the world.
In parallel, second-layer solutions like Lightning, Ark and sidechains enable new functionality, improved scalability and rapid experimentation without requiring changes to the core protocol. This balance allows Bitcoin to evolve without sacrificing its stability or security.
Not at all. Bitcoin's conservatism isn't about rejecting change; it's about ensuring that changes are responsible, necessary, and well-understood. Many conservative bitcoiners welcome proposals like OP_CTV (BIP 119), which offer clear, predictable benefits—such as advanced self-custody, inheritance planning, and payment pools—without introducing unnecessary risk or complexity. We're pro-responsible change, not anti-change. #TeamSlowAndSteady