Bitcoin Forking Guide: Anthony Towns on Building Consensus for Bitcoin Upgrades
Source “A Big Friendly Giant reads the Bitcoin Forking Guide”
Anthony Towns has released a Bitcoin Forking Guide, outlining a structured approach to gaining consensus for changes to Bitcoin’s consensus rules. The guide, shared with Delving Bitcoin, offers a roadmap for developers, users, and industry participants to navigate the complexities of introducing changes to Bitcoin’s protocol.
According to Towns, his guide advocates "consensus before consensus"—the idea that any proposed change should first establish broad social consensus before altering Bitcoin’s core rules.
“It’s only a guide to the cooperative path, where you make a change that makes everyone’s life better, and more or less everyone ends up agreeing that the change makes everyone’s lives better.” — Anthony Towns
Key Stages of Consensus Building
Towns divides the process into four social consensus phases, followed by two final technical steps to integrate the upgrade into Bitcoin Core:
1. Research and Development
Work led by researchers and protocol developers
Focus on idea exploration, theoretical security proofs, and simulations
Ensure the proposed change is necessary, well-documented, and technically sound
2. Power User Exploration
Developers build prototypes and test on signet, regtest, or alternative chains
Red team trials assess security flaws and adversarial risks
Engage power users to explore practical impacts
3. Industry Evaluation
Involves Bitcoin businesses, wallets, exchanges, and miners
Industry feedback determines compatibility and economic feasibility
Ensures businesses can integrate the upgrade without disruption
4. Investor Review
Bitcoin investors, miners, and auditors review the proposed changes
Ensures the change aligns with Bitcoin’s long-term economic integrity
Investors ultimately determine what is adopted as Bitcoin’s consensus
Final Technical Steps
5. Finalization
Formal Bitcoin Improvement Proposals (BIPs) are created
Comprehensive public test vectors are released
A pull request is submitted to Bitcoin Core for final review
6. Activation
Two possible approaches for activation:
Expedited Activation – Requires 90%-95% miner support for a fast rollout
Flag Day Activation – A predetermined upgrade date, ensuring most nodes have updated
Towns emphasizes that true consensus is critical—if an activation method fails, it signals a lack of agreement, requiring a return to earlier phases.
A Path for Cooperative Upgrades
Towns’ Bitcoin Forking Guide provides a structured yet flexible roadmap for implementing changes without central authority. By prioritizing social consensus before technical activation, it seeks to maintain Bitcoin’s decentralized governance model, ensuring upgrades benefit the entire ecosystem.
