Bitcoin's first developer after Satoshi
Martti Malmi (born 1988, Helsinki, Finland) is a software developer who became one of the earliest and most significant contributors to Bitcoin. He studied computer science at Helsinki University of Technology (now Aalto University).
In May 2009, Malmi discovered Bitcoin and contacted Satoshi Nakamoto, offering to help with the project. Their correspondence would grow to approximately 260 emails — the largest known volume of communication between Satoshi and any single individual. These emails were entered into evidence during the COPA v Wright trial in February 2024.
Malmi’s contributions were wide-ranging and foundational. He ported the Bitcoin software to Linux, making it accessible beyond Windows for the first time. He set up and managed the bitcoin.org website, which served as the primary information hub for the project. He also created the original Bitcoin forum (which later evolved into BitcoinTalk), providing the community with its first dedicated discussion platform. Satoshi acknowledged Malmi’s contributions in the Bitcoin 0.2 release announcement (December 2009):
“Many thanks to Martti (sirius-m) for all his development work.”
On October 12, 2009, Malmi sold 5,050 BTC to NewLibertyStandard for $5.02 via PayPal. This is widely recognized as the first known exchange of bitcoin for fiat currency, establishing that bitcoin had real-world monetary value. Malmi later confirmed this transaction on Twitter, stating he made the sale “to help him get the world’s first bitcoin trading service started.”
On December 3, 2010, as Satoshi was stepping back from active development, Malmi asked who should take over Bitcoin-related development and management. Satoshi’s reply was direct: “It should be Gavin [Andresen]. I trust him, he’s responsible, professional, and technically much more Linux capable than me.” This private exchange anchored the formal SVN handover to Andresen on December 12, 2010 and Andresen’s public assumption of project management on December 19, 2010.
Malmi continued occasional correspondence with Satoshi into early 2011. The final known email Satoshi sent to Malmi was on February 22, 2011 — two months before Satoshi’s last private exchanges with Mike Hearn and Gavin Andresen. Malmi gradually reduced his involvement in Bitcoin development around 2011 as other developers took on larger roles. He went on to work in the technology industry in Finland. His early emails with Satoshi, published through the COPA v Wright trial proceedings in 2024, provided invaluable insight into Bitcoin’s formative period and Satoshi’s development philosophy.
31 entries
Satoshi's first reply to Martti Malmi, who had offered to help with Bitcoin. Satoshi praises Malmi's understanding of Bitcoin and asks him to help write website content and a FAQ.
Complete record of all four developers who had commit access to Bitcoin's SourceForge SVN repository. 252 revisions were recorded from August 30, 2009 to September 13, 2011.
Martti Malmi sells 5,050 BTC to NewLibertyStandard for $5.02 via PayPal — the first known Bitcoin-to-fiat exchange, establishing a real-world price of ~$0.001 per BTC.
Context post by sirius in BitcoinTalk topic 12. after msg54.
Bitcoin v0.2 was released on SourceForge, introducing Linux support, multi-processor mining, proxy support for Tor, and GUI improvements contributed by Martti Malmi.
Context post by sirius in BitcoinTalk topic 17. before msg85.
Quoted post by sirius in BitcoinTalk topic 34.
Context post by sirius in BitcoinTalk topic 5. after msg28.
Martti Malmi (sirius) starts a discussion: Make your "we accept Bitcoin" logo.
Quoted post by sirius in BitcoinTalk topic 47.
Context post by sirius in BitcoinTalk topic 58. before msg413.
Context post by sirius in BitcoinTalk topic 59. after msg414.
Context post by sirius in BitcoinTalk topic 60. before msg446.
Context post by sirius in BitcoinTalk topic 63. before msg482.
Context post by sirius in BitcoinTalk topic 88. before msg806.
Context post by sirius in BitcoinTalk topic 101. before msg1134.
Context post by sirius in BitcoinTalk topic 137. after msg1195.
Context post by sirius in BitcoinTalk topic 151. before msg1259.
Context post by sirius in BitcoinTalk topic 177. quoted by msg1814.
Context post by sirius in BitcoinTalk topic 179. before msg1588.
Context post by sirius in BitcoinTalk topic 55. quoted by msg4008.
Context post by sirius in BitcoinTalk topic 184. after msg1609.
Context post by sirius in BitcoinTalk topic 234. after msg1976.
Context post by sirius in BitcoinTalk topic 84. before msg2010.
Context post by sirius in BitcoinTalk topic 326. after msg3157.
Context post by sirius in BitcoinTalk topic 431. before msg3773.
Context post by sirius in BitcoinTalk topic 782. quoted by msg8803.
Context post by sirius in BitcoinTalk topic 850. before msg10067.
The hypothesis that Len Sassaman (cypherpunk cryptographer, died July 3, 2011) was Satoshi. Frame: timing argument and cypherpunk credentials. Counter: no direct documentary link, no widow comment.
Jameson Lopp argues Hal Finney could not have been Satoshi: on April 18, 2009, Finney was running a 10-mile race in Santa Barbara during a window of Satoshi network activity.
During Day 13 of COPA v Wright, Martti Malmi testified via video link and submitted 260 emails (140,000 words) exchanged with Satoshi between May 2009 and February 2011, published on GitHub.