Zcash Engineering Office Hours: Tachyon with Sean Bowe

​Zcash offers the strongest on-chain privacy of any cryptocurrency, but that privacy has come with trade-offs. Syncing a shielded wallet means scanning every encrypted transaction on the blockchain to find the ones that belong to you. Meanwhile, every shielded transaction adds to a growing nullifier set that validators must store forever. Together, these make scaling to billions physically impossible.

​Project Tachyon is a ground-up rethink of how Zcash wallets interact with the network. Led by Sean Bowe, the cryptographer behind Halo and Sapling, Tachyon introduces recursive proof-carrying data and oblivious synchronization: a new model where wallets stay current without revealing what they're looking for, without downloading the entire chain, and without forcing validators to maintain unbounded state. The result is sync times that feel instant and a path to thousands of shielded transactions per second.

​Sean joins us to walk through what Tachyon is, why it matters for Zcash's future, and how it works under the hood. We'll keep the first half accessible, then open up for deeper technical Q&A.

​When: Tues, Mar 17, 2026 @ 12:00 PM EST / 16:00 UTC Where: Zcash Discord Stage
Recording available afterward via Zcash Brazil / ZecHub