Rearden argues we need to shift from thinking about opcodes to thinking about capabilities—the underlying functionalities that Bitcoin can provide. By mapping capabilities to both opcodes and protocols, developers can avoid “magical thinking” and create more concrete, implementable solutions. He presents early capability mapping tables showing how options like CTV and CheckSigFromStack provide efficient solutions for desired protocols like vaults and second layers with unilateral exits.
This presentation was recorded live at 2025’s OPNEXT, the Bitcoin scaling conference. For more info, visit opnext.dev. OPNEXT livestream and VODs are made possible by Taproot Wizards.
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# Notes:
– Current Bitcoin discussions map opcodes directly to protocols
– “Magical thinking” leads to unrealistic protocol designs
– CTV + Check Sig From Stack covers most desired capabilities
– Protocol development should focus on capabilities, not opcodes
– Ergonomic solutions avoid costly auditing requirements
– Incremental approach preferred over comprehensive upgrades
