The version Bitcoin Core v30 has just been made available in test.
Officially, this is not yet a final version, but a release candidate — a stable preview that node operators and developers are invited to experiment with today.
And yet, this simple testing step is already making the community tremble.
Because behind this seemingly innocuous version number lies a much larger debate: that of the very future of the Bitcoin protocol.
A version expected by some, feared by others
Bitcoin Core is the backbone of the network.
This is the software that most nodes use to validate, store, and relay transactions.
Each Bitcoin Core update goes through a battery of tests, reviews, and technical debates that are often discreet… except when a change affects the protocol's philosophy.
And that's exactly the case with v30, a version that revives an old debate: “What are we really allowed to write on the Bitcoin blockchain?”
A little historical reminder
The very first Bitcoin block — the genesis block — already contained text.
Satoshi had written a hidden message there, a nod to the real world:
"The Times 03 / Jan / 2009 Chancellor on brink of second bailout for banks."
A phrase that has become legendary, both a political manifesto and proof of time stamping.
But after this founding gesture, no one “wrote” on the blockchain.
Since then, the unwritten rule has been that Bitcoin remains a ledger—not a wall of entries.
With version v30, this symbolic boundary seems to be cracking again.
The OP_RETURN affair: the fuse of the debate
At the heart of the storm, a small instruction in Bitcoin language: OP_RETURN.
For years, it has allowed a small amount of arbitrary data to be included in a transaction: a text, a hash, a signature, or a time-stamped message.
A tiny door to non-financial uses of Bitcoin.
Until now, this function was strictly limited — to about 80 bytes.
A deliberate choice: to prevent the blockchain from becoming a huge public hard drive, saturated with useless or illegal data.
Because the role of Bitcoin, purists remind us, is to transfer value, not to host files.
What Bitcoin Core v30 changes
The version v30 proposes to lift this limit.
The parameter datacarriersize now moves on to 100 000 bytes, or more than a thousand times more than the historical limit.
For supporters of this change, it is a return to the original neutrality of the protocol:
If a user is willing to pay the fees required to enter their data into a block, the network does not have to censor them.
But for others, it's a dangerous slip-up.
They fear data inflation, node overload, and the appearance of problematic content in the blockchain.
And in a world where regulations are tightening, this prospect is worrying.
A debate that goes beyond the code
What is at stake here goes far beyond technique.
v30 reveals a clash of visions: two conceptions of Bitcoin's future are in direct opposition.
- On the one hand, the “purists”, who defend a monetary, sober and resistant version.
- On the other hand, the “evolutionists” who see Bitcoin as a universal base, a recording layer open to all uses — NFTs, certificates, archives, decentralized applications, etc.
The fracture line is clear:
Should Bitcoin be protected from complexity, or opened to the world?
⚙️ Tech Focus Insert — Will it take more power to run Bitcoin?
Technically, the update v30 does not change Bitcoin's consensus rules.
The maximum block size remains the same, and the hardware requirements remain unchanged… at least, for now.
Where things get complicated is with the lifting of the cap on arbitrary data (OP_RETURN).
If this new margin of 100 000 bytes is massively exploited, the network could see many more “heavy” transactions — messages, images, certificates, or various data recorded in the blockchain.
Result : more data to download, relay, store.
Today, a full node requires approximately 600 GB of disk space, 2 to 4 GB of RAM and stable bandwidth.
But if “non-monetary” uses explode, these figures could climb:
- up to 1 To disk space in the coming years,
- and more bandwidth to relay heavier blocks.
This scenario is not yet a reality, but it fuels a concern: that of a centralization through complexity.
If only the most equipped can run a node, the promise of decentralization weakens.
A last-minute turnaround
Faced with criticism, Bitcoin Core developers adjusted their stance even before the test release.
The controversial parameter will not be imposed by default: each operator will be able to choose to limit the size of authorized data itself (datacarriersize).
It's a compromise.
But the tension remains palpable: this simple line of code was enough to rekindle the most sensitive debates in the history of the protocol.
The question of the integration of illegal content...
Some developers, notably those from Bitcoin Knots, reacted strongly.
For them, this development is a step too far: it threatens the stability of the network and risks discouraging small node operators, already subject to increasing technical constraints.
The famous cryptographer Nick Szabo He also warned of the legal risk: “If illicit data is inserted into the blockchain, who will bear responsibility?”
In a context of increased digital surveillance, this question becomes central.
Indeed, Indeed, this fear is not theoretical.
In the past, some experiments have already shown that it is possible to register in the blockchain pornographic images or content, or other illegal files.
This data, once engraved in the blocks, is impossible to erase — this is both the strength and the weakness of the system.
If the size allowed by OP_RETURN widens, the risk of abuse increases : malicious individuals could insert prohibited or sensitive files into the chain, voluntarily or not.
This would put node operators—those who hold a full copy of the blockchain—in a legally murky situation.
Are they simply neutral hosts? Or are they, in spite of themselves, becoming the owners of illegal content?
What you must remember
- The version Bitcoin Core v30 is available today for testing (release candidate).
- The parameter
datacarriersizego to 100 kB, allowing the insertion of much larger data into the blockchain. - Nodes will, however, be able to set their own limit—a concession reached after heated debate.
- The community is divided between two visions: Bitcoin as “pure currency” or as “open infrastructure”.
- This update does not change the consensus, but it profoundly questions the governance of the network.
