Early Days of Ethereum

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Felix Lange

Felix Lange

(Oct 2014 to present)

DEVCON0 self-introduction

Felix Lange DEVCON0 introduction

Felix Lange is the architect of Ethereum's peer-to-peer networking layer and possibly the longest-serving Ethereum Foundation employee after Vitalik Buterin. He has been building and maintaining how Ethereum nodes communicate with each other since October 2014.

Joining the Geth Team

Felix joined Jeff Wilcke's ÐΞV Amsterdam team in October 2014 as a Go developer. Jeff introduced him in his first development update:

"Felix is a die-hard Gopher (yay!) and the first thing he pointed out to me was that I had done a bad job looking after my go routines and there were a lot of race conditions, so nice of him. Felix is going to work on the Whisper implementation once the spec has been formally finalised. Felix is a super star gopher and has the ability to become a true Ethereum Core Dev."

Though hired by the Amsterdam team, Felix was based in Berlin, literally living across from the office.

The Network Layer

Felix rewrote the P2P networking package for Geth and has maintained the devp2p protocol stack ever since. Fabian Vogelsteller highlighted Felix as a prime example of unrecognized contribution:

"That dude literally built the, and is building still the communication layer of the Ethereum network and how the nodes talk to each other. And he has done that without fame or attention for years." — Fabian Vogelsteller (Episode 12)

"Just a Janitor"

Felix is known for his humility and discomfort with attention. Bob Summerwill recalled a conversation in Buenos Aires:

"He's such a humble guy. He was saying to me, 'I really don't like Early Days of Ethereum, I don't want the attention.' I was saying to him, 'you're like the longest serving person at the EF, I think after Vitalik.' He's like, 'I'm just like a janitor. I just turn up and I maintain the thing. I don't want any of that focus. It was just like a job for me.'" — Bob Summerwill (Episode 12)

Felix notably never bought any Ether, with a purely pragmatic rationale: "If I don't have a use for Ether, if I don't want to build an app, why would I need some?" Fabian organized a team-wide donation so Felix would have at least some reward for his work.

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