Ross Unveils Tacit Chain, a Private Payments Rollup on Ethereum
Tacit Chain is a prototype ZK rollup on Ethereum for private TAC payments, with post-quantum memo encryption and a Stage 2 design.
Prolific indie dev Ross (z0r0z) wants crypto to finally pass the coffee test. In a new X Article on Sunday, Nov. 8th, he introduced Tacit Chain, a prototype ZK rollup for fast, private payments in TAC, the token of Tacit, the confidential Bitcoin DeFi project we covered in June.
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What's the Scoop?
How it works: Users prove their own payments on their own devices. A rotating "leader" then groups those payments into blocks, and Ethereum checks each block with a single proof. Staking 1,000 TAC buys a seat in the leader rotation, and if a leader goes 10 minutes without posting, anyone can post the next block. Amounts and counterparties stay hidden on the chain, though deposits and exits to Ethereum are public.
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Post-quantum privacy, not proofs: Payment memos are encrypted with ML-KEM, NIST's post-quantum standard, on top of today's elliptic-curve cryptography. That guards against "harvest now, decrypt later" attacks, where someone stockpiles encrypted data until quantum machines can crack it. The rollup's proofs aren't quantum-safe, though, and Tacit's docs say so.
Paid to stay: There's no protocol fee. Part of every payment plus a 0.1% exit fee stays in the shared pool, so holders' balances grow as the chain gets used. That rewards users who keep funds inside, which makes the crowd every private payment hides in bigger. TAC holders can enter from Ethereum without paying gas or from Bitcoin through Tacit's bridges, and exits skip the week-long wait.
A Stage 2 claim: The chain has no owner, upgrade key, or multisig, and users can force their transactions through Ethereum, so a leader can only hold them up for about an hour. Ross says that clears Stage 2, the top tier on rollup risk tracker ETHBEAT. He invited ETHBEAT to "take a look and roast" it, but no assessment is out yet.
Still day two: Since going live Nov. 7th, Tacit Chain has landed 27 blocks and holds about 4,677 TAC (roughly $600). Every block so far came from Tacit's starter leader address, since no one has staked a seat yet. The main contract went from first commit to mainnet in about 38 hours.
William M. Peaster
William M. Peaster, Senior Writer, has been with Bankless since January 2021. Immersed in Ethereum since 2017, he covers the onchain frontier with a particular interest in art, games, and other culture apps. He has a background in creative writing and writes fiction in his free time.
