Mike Hearn

Hearn began programming at the age of six. His father, who worked in the British television industry and was interested in computers, ran a small software business in the early 1980s before returning to television. From about the age of 14 Hearn contributed to open-source projects over a dial-up connection.⁠[1]

In 2004 he enrolled at Durham in the United Kingdom; he found the theory-heavy teaching less useful than hands-on work.⁠[1]

In 2006, while still a student, Hearn was recruited by a Google headhunter and joined the company after a three-month training program in California. He began in server operations and then spent about three years on the on-call operations team for Google Maps and Google Earth, working on satellite imagery, tile-serving infrastructure, traffic management and network monitoring, and took part in the rollout of vector maps.⁠[1]

He then joined Gmail’s anti-spam team, writing tools to find and remove networks of spammer-controlled accounts, and worked on BotGuard, a system aimed at automated abuse of Google sites, as well as on anti-hijacking work. He was a senior software engineer at Google and has said he worked there for nearly eight years.⁠[1][2][3]

“I had always been interested in new kinds of money since I was a teenager,” Hearn said. He was drawn to Bitcoin as it grew around 2010 and used Google’s 20-percent time policy to work on Bitcoin projects in his spare time.⁠[1]

While working for Vinumeris, a Bitcoin consulting and development startup, he helped build Lighthouse, a peer-to-peer crowdfunding app using Bitcoin smart contracts. He has said he spent more than five years as a Bitcoin developer and that his software was used by millions of people.⁠[1][3]

In July 2015 Andreessen HorowitzAndreessen HorowitzAndreessen Horowitz (a16z) is a venture capital firm founded in 2009 by Marc Andreessen and Ben Horowitz. It invests from the seed stage through the growth stage and provides operational support to its portfolio companies.Open the full entry released the a16z Podcast episode “a16z Podcast: Bitcoin's Growing Pains — and Possibilities,” in which Chris DixonChris DixonChris Dixon is a programmer, entrepreneur, and venture capitalist, and the founder and managing partner of a16z crypto. He co-founded SiteAdvisor and Hunch, helped create Founder Collective, and later joined Andreessen Horowitz, investing in technology companies such as Coinbase. He is also the author of Read Write Own and has long written about blockchains, network ownership, the open internet, and the combination of AI and crypto.Open the full entry of Andreessen Horowitz spoke with Hearn, introduced on the episode page as a “core bitcoin developer”; Sonal Chokshi was also listed on the episode.⁠[4]

The episode discussed whether Bitcoin’s block size needed to grow to add capacity, the state of Bitcoin development, Hearn’s crowdfunding app Lighthouse, and what it would take to bring the Bitcoin protocol into the mainstream.⁠[4]

Hearn co-developed Bitcoin XT, software implementing the BIP 101 proposal to raise Bitcoin’s block size limit through miner voting; he said XT gained significant node support but faced DDoS attacks, and that discussion of it was censored on the official Bitcoin forums.⁠[3]

On September 2, 2015, Andreessen Horowitz released the a16z Podcast episode “a16z Podcast: Hard Forks, Hard Choices for Bitcoin.” The episode page explained that Hearn and others had proposed Bitcoin XT as a hard fork but that not everyone in the community supported that approach, so the episode invited Adam Back, inventor of hashcash and co-founder of Blockstream, and Alex Morcos, founder of Chaincode Labs, to discuss other options for solving Bitcoin’s scaling problem. The episode was uploaded to the a16z YouTubeYouTubeYouTube is Google’s video-sharing and creator platform, founded in 2005 by Steve Chen, Chad Hurley, and Jawed Karim and acquired by Google in 2006. Built around video uploading, viewing, and creator earnings, the platform has developed Shorts, YouTube Music, Premium, YouTube TV, and products for children, and is headquartered in San Bruno, California, United States.Open the full entry channel on January 1, 2019, as “a16z Podcast | Hard Forks, Hard Choices for Bitcoin.”⁠[5][6]

In 2015 Hearn joined R3 CEV, a banking consortium selling distributed ledger technology to banks. In November 2015 he began building Corda, a blockchain-inspired distributed database for the financial industry intended to reduce manual data synchronization; after meeting R3 chief technology officer Richard Brown, he joined R3 full time as lead engineer.⁠[2][1]

In January 2016 Hearn published “The resolution of the Bitcoin experiment,” writing: “I will no longer be taking part in Bitcoin development and have sold all my coins.”⁠[3][2]

In the post he argued that the 1 MBMercado BitcoinMercado Bitcoin (MB) is a Brazilian digital-asset platform within the 2TM group, offering cryptocurrency trading, asset tokenization and financial services.Open the full entry block size cap had never been lifted and that the network was nearly out of capacity, blaming Chinese miners who controlled most of the hash power and Bitcoin Core developers who refused to raise the limit. “Bitcoin has no future whilst it's controlled by fewer than 10 people,” he wrote.⁠[3]