Bitcoin Core v30 Rolls Out Amid Controversy Surrounding OP_RETURN Modification

Key Takeaways:

• Bitcoin Core v30 enhances performance and privacy but is divisive due to its larger OP_RETURN data limits.
• Critics argue this shifts Bitcoin from its original vision, while proponents see it enabling new, practical applications.
• Emergence of developments like Bitcoin staking confirms that technical innovation continues to progress.

On October 11, Bitcoin Core rolled out its major v30 update. The release introduced key improvements to node architecture, performance, and security, aiming to make the Bitcoin network faster. However, the community has been sharply divided over the increase in the OP_RETURN data limit.  

Critics Say the Bitcoin Core Update Undermines the Network’s Core Principles

The Bitcoin Core v30 upgrade introduces optional encrypted connections between nodes to improve privacy. The release also includes bug fixes, performance boosts, and refined fee adjustments to make transactions faster.

But a change in the OP_RETURN structure has become the centre of controversy. The update increased its data limit from 80 to 100,000 bytes. 

This upgrade allows users to store much larger amounts of non-financial data on the blockchain. 

With this, digital art metadata, tokens, and small pieces of code can now be embedded directly into Bitcoin transactions. 

Critics argue that this capability strays from Bitcoin’s original mission as a peer-to-peer electronic cash system. 

They contend that storing arbitrary data through OP_RETURN adds unnecessary clutter and bloats the blockchain, which can increase the operational costs and complexity of running a full node, potentially undermining network decentralization. 

In response to these changes, some operators have adopted alternative software like Bitcoin Knots, which maintains the original 80-byte OP_RETURN.

Pioneer cryptographer Nick Szabo added weight to this cautious approach. Before the Bitcoin Core v30 launch, he advised node operators to temporarily switch to Knots and avoid upgrading to the new version. 

As a (hopefully) temporary measure, run Knots. I strongly recommend not upgrading to Core v30.https://t.co/d9HFi7T59H

— Nick Szabo (@NickSzabo4) October 8, 2025

Szabo believes that any change encouraging data storage or application layers could weaken Bitcoin’s reliability as digital gold.

Supporters See Greater Utility and Innovation in Bitcoin’s Future

While some critics warn of mission drift, others believe the new OP_RETURN limit opens fresh possibilities for Bitcoin’s utility.

Developers like Alex Bergeron, ecosystem lead at Ark Labs, are among its strongest supporters. He shared plans to utilize the expanded OP_RETURN capacity to develop applications that enhance the versatility of Bitcoin.

Even better, Bergeron believes this can be achieved without compromising security and decentralization. 

I fully intend to use all of the additional OP_Return space and WILL use it to make Bitcoin more like Ethereum, except better.

Thank you for your attention to this matter.

— Alex B 👾 (@bergealex4) October 10, 2025

Satoshi Labs co-founder Pavol Rusnak echoed similar optimism. He expressed support for Bitcoin Core v30 because it represents disciplined engineering and peer-reviewed code. 

To him, the update shows that Bitcoin can evolve cautiously while maintaining its core design philosophy.

Recent developments beyond the upgrade also indicate how Bitcoin's utility is expanding into new directions. 

On September 30, Starknet announced a Bitcoin staking service. The system lets users stake their Bitcoin to help validate transactions on a separate layer. Rewards will be earned while keeping full custody of their assets.

Still, this positive development was not well-received. Bitcoin purists argued that staking goes against the original proof-of-work model that secures the Bitcoin network. 

The divide seems inevitable,  as more projects explore smart contracts, staking, and other new functions, tension over Bitcoin’s true direction is likely to grow.