Nikolas Sargeant
Bitcoin Core v30.0 was officially released on October 11, 2025, marking one of the most controversial updates to the Bitcoin network's reference software since the 2017 scaling wars. Bitcoin Core is the primary software implementation that powers roughly 95% of Bitcoin's full nodes and defines standard network behavior. The update increases the default OP_RETURN data limit from 80 bytes to 100,000 bytes while allowing multiple arbitrary data outputs per transaction for the first time in over a decade. Node operators can now download the software, though the release has sparked intense debate within the Bitcoin community about the network's core purpose and potential legal implications.
The release completely removes Berkeley DB legacy wallet support, forcing users to migrate to descriptor wallets before upgrading. Additional improvements include experimental Stratum v2 mining infrastructure through a new IPC interface, TRUC transaction support for better Lightning Network fee-bumping capabilities, and aggressive fee rate reductions to 0.1 sat/vB from the previous 1.0 sat/vB minimum. Critically, v30 contains zero consensus changes. It modifies only policy rules affecting what individual nodes relay and store, not the protocol's fundamental validation rules.
The controversial OP_RETURN expansion has divided the community, with proponents arguing it aligns node software with existing miner behavior while reducing harmful UTXO set bloat. Critics warn the change transforms Bitcoin into a data storage platform and exposes node operators to legal liability for potentially hosting illegal content. Bitcoin Knots nodes have surged from 2% to 20% of the network as operators rejected Core's new defaults, while Bitcoin pioneer Nick Szabo returned from a five-year social media hiatus to warn of "legal nightmares" ahead.
For most Bitcoin users running external wallets like Ledger, Electrum, or mobile apps, the update requires zero action; these wallets remain fully compatible. However, the approximately 25,000 nodes securing the network and exchanges custodying billions in Bitcoin face critical decisions about whether to adopt v30's defaults, configure stricter limits, or switch to alternative implementations like Bitcoin Knots that maintain conservative policies.
