Aztec activates Tierra v6 as its alpha mainnet

Aztec activated Tierra, or Alpha V6, as the current release of its privacy-focused Ethereum layer 2 on November 3. The network’s status page identifies v6.0.0 as its alpha mainnet and marks a critical V5 proving-system vulnerability resolved, making the change a security migration as well as a feature upgrade.

Tierra is a new rollup deployment from genesis rather than an in-place software patch. Its circuits, verification-key tree, contract-address derivation and block headers differ from V5. That separation is intended to prevent proofs created for the affected system from carrying into V6, but it also means contracts and network infrastructure cannot move over unchanged.

V6 closes a disclosed proving-system incident

Aztec contributors said they discovered the V5 flaw during internal, AI-assisted auditing on July 27 and disclosed it August 7. The vulnerability could have allowed a proof to pass verification for a transaction that the protocol should reject, creating an invalid state transition.

The project could not determine whether the flaw had previously been exploited. Its disclosure said V5 lacked the information needed to distinguish ordinary transactions from ones accepted through the faulty proving path, so historical activity could neither settle that question nor quantify any possible impact. Tierra’s activation resolves the known incident prospectively; it does not reconstruct what happened before discovery.

Aztec’s November 3 status record reports no active incident for Tierra and says the V5 finding is fixed in v6.0.0. The network remains explicitly labeled alpha, however. That maturity label matters: resolution of one identified vulnerability is not evidence that the new proving system, contracts or applications contain no undiscovered faults.

A breaking migration, not a routine node update

The v6.0.0 code release was tagged October 22, before governance made the new rollup canonical. Operator documentation calls the migration difficult and requires a fresh data directory because no V5 chain state carries over. Repository locations, container images and package scopes also changed; an operator still pulling the old image will receive V5 software that cannot participate in the V6 network.

Application developers face a comparable boundary. Every verification key changes, while a new address-domain separator means equivalent contract inputs produce different addresses on V6. Contracts therefore need recompilation and redeployment rather than assuming continuity with their V5 addresses or proofs.

Governance records show that the transition also changed protocol economics. The sequencer share of each 500-AZTEC checkpoint reward rises from 70% to 90%, while the total checkpoint reward remains unchanged. A separate fee-margin mechanism launches at zero, so the upgrade creates a future governance control without immediately adding that charge.

Faster messaging is a protocol estimate

The release replaces a two-checkpoint inbox delay with a design that streams Ethereum-to-Aztec messages into blocks as nodes observe them. Aztec estimates this reduces the delivery window from 24–108 seconds under V5 to roughly 12–30 seconds under V6. Those ranges are engineering estimates in the release materials, not an independently measured production dataset, and actual deposits can still vary with Ethereum confirmation and network conditions.

Aztec separately reports client-side private proofs taking about one second on a native device, approximately twice as fast as the prior network. The launch announcement does not provide a complete hardware matrix or independent reproduction, so the figure should be read as a project benchmark rather than a universal user result.

The upgrade package says its transition logic received unit, scenario and fork-simulation testing, but its public governance document still lists the audit field as “TBD.” Tierra therefore establishes that V6 is live and that the known V5 proving flaw has a replacement path. It does not establish audited security across every component, successful migration by every application or realized performance under sustained production load.