Kevin presents Spark, a protocol from Lightspark that addresses Bitcoin Lightning Network’s limitations. Built on enhanced state chains, Spark offers instant, cheap transactions that work offline with native Bitcoin integration. Kevin demonstrates how Spark enables self-custody at scale and seamlessly supports stablecoins—without requiring new opcodes. The presentation includes live demos of Coinbase-to-Spark transfers, stablecoin payments to phone numbers, and direct Bitcoin-to-bank transactions via Universal Money Addresses.
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:
– Lightning can’t handle self-custody for 1B+ users
– $400 inbound liquidity per user = $100B locked
– Standard state chains have time limitations
– Spark operators sign things and forget keys
– Spark architecture supports unilateral exit
– Uses linear aggregation for distributed security
