Chronicle upgrade on BSV mainnet clears path for Teranode

The BSV blockchain reached a historic milestone on April 7, 2026, as the Chronicle protocol upgrade was activated at block height 943,816. It marks the completion of Bitcoin’s original protocol restoration and sets the stage for the coming Teranode Era.

The activation occurred at approximately 9:13 PM UTC, representing the final evolution of the SV Node protocol. Officially “SV Node v1.2.0,” Chronicle restores the complete technical vision outlined by Satoshi Nakamoto in the original 2008 Bitcoin white paper. It removes the last artificial limitations introduced to Bitcoin over the years and re-enables capabilities that were always part of the design.

BSV network node operators (“miners”) should already have upgraded their software by now, but running Chronicle is necessary to stay in consensus with the network (unless they’re already running Teranode, that is).

What Chronicle delivers

The Chronicle release expands the BSV protocol’s capabilities, while maintaining full backward compatibility for existing transaction types. Essentially, Chronicle completes the Genesis upgrade process that began in 2020 that had restored many aspects of Bitcoin’s original protocol but left certain technical restrictions in place.

Among Chronicle’s key improvements is the reinstatement of disabled script OP_CODEs, reintroducing functionality present in Bitcoin’s initial release but later removed due to concerns about potential vulnerabilities. These OP_CODEs expand the expressiveness of Bitcoin’s scripting language, enabling more sophisticated smart contracts and transaction types without requiring off-chain solutions or secondary protocols.

The upgrade also implements the Original Transaction Digest Algorithm (OTDA), giving developers the option to use Bitcoin’s native signature hashing method rather than the later modified BIP143 algorithm. Users can opt into OTDA by setting the new CHRONICLE [0x20] sighash flag, while existing transactions continue to function exactly as before.

Perhaps most significantly, Chronicle removes malleability-related restrictions for transactions that opt in through version numbers greater than 0x01000000. This removes constraints, including: the minimal encoding requirement; low-S signature requirements; NULLFAIL and NULLDUMMY checks for signature operations; MINIMALIF requirements for conditional logic; and clean stack requirements. These restrictions had been implemented to prevent “transaction malleability attacks,” but came at the expense of reduced flexibility in Bitcoin Script development.

“Transaction malleability was a concern based on a misunderstanding of the payment flow, and a misunderstanding of nodes themselves,” said Connor Murray, Head of Protocol Stability at BSV Association. “Because they misunderstood how payments should work and are convinced that miners will behave irrationally, they put in a bunch of restrictions on developers.”

The upgrade also expands the consensus limit on Script number size from 750KB to 32MB, while still allowing node operators to maintain their own policy limits through the “maxscriptnumlengthpolicy” configuration parameter.

Looking to the Teranode future

While Chronicle completes Satoshi’s original vision, it also serves as a bridge to BSV’s next major evolution: Teranode. The Teranode protocol, which already processes blocks on the BSV network but isn’t (yet) ubiquitous, provides the infrastructure necessary to process the massive transaction volumes that unrestricted block sizes will inevitably bring. It has already proven capable of handling over a million transactions per second.

Chronicle finalizes the protocol foundation that Teranode will then build on. It ensures that when the next-generation node software becomes available, it will operate on fully restored Bitcoin capabilities rather than artificially constrained ones.

A six-year journey

The path to Chronicle has been a careful one. Following the “Genesis” restoration of Bitcoin’s original rules in 2020, the BSV ecosystem focused on demonstrating that unbounded block sizes were not just theoretical, but something achievable in reality. That demonstration has succeeded, with the BSV network regularly processing blocks larger than those on any other public blockchain.

Chronicle, therefore, represents the final achievement of that phase. With the protocol now fully restored, attention shifts to implementing Teranode across the wider network and the industrial-scale transaction-processing capabilities it will unlock. For businesses and developers building on BSV, it shows the platform’s technical foundation is complete, stable, and ready for enterprise-tier deployment at any size.

The Chronicle activation is both an end and a beginning. It’s the starting point for Bitcoin to finally fulfill its original purpose: as a global electronic cash system capable of handling all the world’s data.

Watch | Teranode explained: BSV leaders on blockchain scaling & the future of digital economy