Martti Malmi

Early Bitcoin Developer · Finland

Martti Malmi, known as sirius, is the Finnish developer who worked directly with Satoshi Nakamoto as Bitcoin's second contributor, building the early software, the bitcoin.org site, and the first community forum. He made one of the first known Bitcoin-for-fiat sales, 5,050 BTC for about $5 via PayPal in 2009, and in 2024 released his archive of Satoshi emails as evidence in the COPA v. Craig Wright trial. Today he develops Iris, a Nostr client for decentralized social networking.

At BTCHEL 2026

https://x.com/marttimalmi · https://njump.me/npub1g53mukxnjkcmr94fhryzkqutdz2ukq4ks0gvy5af25rgmwsl4ngq43drvk

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