In November of 2008, I did a code review and security audit for the block chain portion of the Bitcoin source code.
The division of labor went like this: I reviewed the blockchain code, Hal Finney reviewed the scripting language, and Satoshi alternated between answering our questions and asking his own.
In May 1995, as a research paper in a graduate networking class, I had created what I believe is the first digital-cash protocol ever to use block chains.
I found Satoshi’s cryptographic code tight. I identified two concerns: first, the early network’s vulnerability to attacks by powerful actors, and second, potential scaling and bandwidth problems at larger network sizes.
After launch, I saw no reason to expect a nonzero valuation for proof-of-work hashes, and believed the bandwidth requirements made it impractical. So I stepped back.
Bitcoin was the first digital cash system with no Trusted role at all. Satoshi built a highway with no toll bridge. He wasn’t selling coins, he was giving them away for solving hashes.
Satoshi mined approximately one million bitcoins but never sold any. This demonstrated genuine disinterest in personal enrichment.
In the aftermath, over 3,000 altcoins followed. Most of them do know what they’re doing, and at least three quarters know that what they’re doing is ripping people off.
Many ICOs resemble blatant stock price manipulation and insider trading. Legitimate blockchain use cases have become caught in the fire and burned by scam association.
[Published on LinkedIn, September 20, 2017. Reached the front page of Hacker News on September 21, 2017, receiving 329 points and 86 comments.]