Sean Bowe and Jack Grigg aka str4d are both cryptographic engineers working on the Zcash protocol. Sean’s latest project is Tachyon, intended to bring encrypted money into the hands of 8 billion people.

Topics we discuss are well captured by the timestamps below.

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Timestamps

0:00 - Project Tachyon

10:20 - Privacy can’t be an afterthought for a protocol

15:24 - Encrypted Bitcoin

22:11 - Soundness bug in original sprout pool

30:15 - Sapling

33:00 - A decade of progress

39:04 - Zcash’s anonymity set

51:29 - Using private money as a passthrough doesn’t work

56:04 - The importance of ledger indistinguishability

58:30 - The ultimate privacy stack

1:05:58 - Tachyon removes all cryptographic bottlenecks of encrypted money

1:08:16 - What’s next after Tachyon?

1:15:25 - Weightless blockchains?

1:18:24 - Ragu

1:19:44 - What the next 12 months look like for Jack and Sean

1:31:22 - “Everything worth doing is worth doing on ambitious timelines.” — Sean

1:32:16 - Sean’s advice for young engineers

1:34:18 - What got Sean and Jack into Zcash?

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