Adam Back · life event
2026-10-23 primary
📌 Upcoming: “From Hashcash to Bitcoin” fireside chat at Plan ₿ Forum, Lugano
Adam Back
@adam3us
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Inventor of Hashcash, cited in the Bitcoin whitepaper; co-founder and CEO of Blockstream
Cypherpunk and cryptographer. In 1997 he proposed Hashcash, the proof-of-work that Bitcoin mining uses. In 2008 Satoshi emailed him before publishing the whitepaper, and he pointed Satoshi to Wei Dai's b-money. In 2024 he testified in COPA v Wright.
Cited in whitepaper [6]
Joined: 2008-08-20 · Received Satoshi's first known email, 20 Aug 2008 · bitcoindefense.org ↗ primaryLocation: Malta (public X profile) · x.com ↗ primary
Museum format: every post is a real, sourced quote. Quotes stay in the original English; the Russian line is our translation.Source badges on this profile: primary 23 · secondary 3 · unconfirmed 0
Adam Back · life event
2024-03-14 primary
📌 Testifies in COPA v Wright; the court rules that Craig Wright is not Satoshi
Adam Back · life event
2018-09-27 primary
📌 Blockstream's Liquid sidechain produces its first block (launch announced 10 Oct)
Adam Back · life event
2014-10-22 primary
📌 Co-authors the pegged sidechains paper; Blockstream announces its $21M seed round on 17 Nov
Adam Back
2013-04-18 · via BitcoinTalk ↗ primary
“In fact I believe it was me who got Wei Dai's b-money reference added to Satoshi's bitcoin paper when he emailed me about hashcash back in 2008.”
Adam Back · life event
2008-10-31 primary
📌 The Bitcoin whitepaper cites Hashcash as reference [6]
Adam Back · life event
2008-08-21 primary
📌 Replied to Satoshi: the citation looks right; pointed him to Wei Dai's b-money
Adam Back
2002-08-01 · via paper ↗ primary
“The hashcash CPU cost-function computes a token which can be used as a proof-of-work.”
Adam Back
1997-03-28 · via cypherpunks mailing list ↗ primary
“Hashcash is free, all you've got to do is burn some cycles on your PC.”
Adam Back
1997-03-28 · via cypherpunks mailing list ↗ primary
“The idea of using partial hashes is that they can be made arbitrarily expensive to compute (by choosing the desired number of bits of collision), and yet can be verified instantly.”
Adam Back
1995-03-09 · via cypherpunks mailing list ↗ primary
“Heres a bit of perl code which implements RSA encryption and decryption and is small enough to use for a signature”