The Scaling Bitcoin conference, held at the Politecnico Milan , returned for its third iteration this weekend, with the focus throughout the speaking slots and workshops shifting away from scaling alone. Emphasizing that Bitcoin faces a more diverse set of challenges, this year’s edition of the technical conference included a broad range of topics. Chief among them was fungibility — the idea that each bitcoin should be as valuable as any other bitcoin, regardless of transaction history. The tone for this third Scaling Bitcoin edition was set with the workshop’s first overview presentation by program chair and Blockstream developer Matt Corallo, and newly appointed Blockstream CEO Dr. Adam Back. “If there are doubts about coins you receive, then people are going to go to taint services and check whether these coins are ‘blessed,’” Back explained. “And [if not], then people are going to refuse to trade them. What this does is it transitions bitcoin from a decentralized permissionless system into a centralized permissioned system where you have an ‘IOU’ from the blacklist providers.” Following up on Corallo and Back’s opening presentation, the first half of the first conference day focused on fungibility exclusively. Speakers presented proposals that included JoinMarket, a marketplace for CoinJoin transactions to aggregate several transactions into one bigger transaction, and TumbleBit, a trustless mixing service. A dedicated workshop continued the discussion that same afternoon. Fungibility remained on top of everyone’s mind throughout the weekend — optimistically — with topics including Schnorr signatures to incentivize CoinJoin transactions, coin-selection schemes for improved privacy, and BIP 151 for end-to-end encryption. “Most of the [scalability improvements] have not been implemented or don’t have heavy use,” said Corallo in the conclusion of his opening talk. “But we do know how to fix Bitcoin and make it act like what we want […]
