Key Takeaways
Zebra completed a major transaction type refactor and is addressing performance and consensus-related issues before its next release.
Zallet Beta 3 shipped with migration fixes and changes addressing findings from the Least Authority security audit.
Zaino is modularizing its indexing architecture to improve flexibility and sync performance.
NU7 work continues alongside discussion around the Network Sustainability Mechanism and alternative ZIP 234.
Draft ZIP 248 introduces a future-extensible transaction format, while transaction fee policy remains under discussion.
ZIP 316 Revision 2 is nearing implementation, improving support for standalone account-level viewing keys.
Zcash formalization work has expanded, with balance and validity games now formalized.
Early implementation work on P2P v2 is underway in Zebra.
Zebra: Transaction Refactor & Performance
The Zebra team completed a major refactor of its transaction types, replacing Zebra’s duplicated transaction representation with a wrapper around the upstream zcash_primitives transaction type.
The change touched more than 5,000 lines of code and removes duplicated transaction logic, clearing the way for further integration work.
Following the refactor, the team identified a performance regression in script validation and is working on a reported consensus-divergence issue. Both are currently blocking the next Zebra release, so there is no confirmed release date yet.
Peer management was also hardened by applying connection limits across IPv6 /64 groups, while a mempool issue involving download slots was fixed.
Additional Zebra work included:
Bounding
getaddressutxosby the requested height range and limit.Moving mining RPC tests toward regtest, significantly reducing CI time.
Making Zebra state snapshots available for faster node bootstrapping.
Replacing Mergify with GitHub’s native merge queue.
Fixing a near-tip synchronization restart loop.
Work is continuing on mining and mempool performance, verification caching, and P2P v2, with early P2P v2 implementation already underway.
Zallet Beta 3 & Core Libraries
Zallet Beta 3 has shipped, addressing migration-path issues reported by miners as well as findings from the Least Authority security audit.
All identified audit issues have now been addressed, and the audit has entered its second round of review as the fixes receive feedback and acknowledgement.
Several miners have already moved to Zallet full-time, while work is underway on a smaller and faster Beta 4 release.
Migration from zcashd remains an active area of work, particularly around edge cases involving legacy wallet.dat files.
Core library work also continues across several areas, including NU7 protocol and ZIP preparation, wallet correctness fixes in zcash_client_sqlite, the mobile SDK release and versioning backlog, upcoming Tachyon and v7 work in librustzcash, and review of Zcash P2P v2 work.
ZIP 248 & Transaction Format
Kris called for additional review of draft ZIP 248, which covers a future-extensible transaction format.
One possibility discussed is using the new format to clean up legacy coinbase transaction behavior through a dedicated coinbase bundle. Such a design could also leave room for future miner signaling, including fee-floor signals recorded onchain.
Separately, work is underway to upstream or backport performance improvements from Valar Group’ forks into the Zcash core libraries. Danny Williams is leading this effort, with several pasta_curves pull requests currently seeking additional review.
Transaction Fee Discussion
The ZIP editors are considering a Shielded Labs proposal to reduce the marginal ZIP 317 fee to 1,000 zatoshis per logical action.
The call also explored a broader change to how Zcash transaction fees could be adjusted in the future. Kris proposed potentially removing ZIP editors from routine fee adjustments and using historical ZEC/USD price data to calculate a minimum fee denominated in USD.
The idea would allow fees to respond systematically to changes in ZEC’s market price rather than requiring repeated manual adjustments.
Pili expressed reservations about anchoring transaction fees to USD, while Zooko suggested continuing the discussion separately, testing competing approaches, and potentially seeking independent mechanism or economic analysis.
No decision was reached, and the fee mechanism remains under discussion.
Zingo Labs: Zaino
Zaino is undergoing a significant internal modularization of how its indexes are constructed.
Under the new architecture, individual indexes will become configurable and opt-in, allowing operators to build only the indexes they need. This includes the ability to disable compact-block indexing when it is unnecessary for a particular use case.
The goal is to reduce unnecessary computation and improve synchronization performance across different deployments.
Zaino has also merged and released mempool and security fixes while expanding its testing and observability infrastructure. Full-sync testing, blocks-per-second measurements, and CPU flame graphs are being used to identify additional performance bottlenecks and optimization opportunities.
Snapshot support is also being explored. Once the sync modularization is complete, Zaino could potentially generate snapshots for individual indexes or tightly coupled groups of indexes, reducing initial synchronization time and helping operators reach uptime faster.
Network Sustainability Mechanism & NU7
Shielded Labs’ work on the Network Sustainability Mechanism (NSM) is currently focused on the results of the NU7 Coinholder Poll.
The call also requested additional review of the alternative draft ZIP 234, which proposes an NSM design that preserves Zcash’s existing halving schedule.
The discussion remains part of the broader work around NU7 and Zcash’s future issuance and sustainability mechanisms.
Zcash Formalization
Formalization work continues, with the balance and validity games now formalized.
The effort has also expanded beyond the circuit to cover additional areas of the Zcash protocol.
A dedicated blog post is expected to provide a more detailed update on the formalization work.
ZIP 316 Revision 2
Implementation of ZIP 316 Revision 2 is nearly ready to land.
The update is particularly important for wallets that need to represent standalone account-level viewing keys, including functionality needed when importing legacy zcashd wallets.
The next goal is to move the implementation into production and encourage broader adoption across the wallet ecosystem.
Looking Ahead
Development continues across nearly every layer of the Zcash stack. Zebra is working through the final issues following its major transaction refactor, Zallet is moving toward Beta 4, and Zaino is restructuring its indexing architecture around faster and more configurable synchronization.
At the protocol level, NU7 preparations continue alongside discussions around the NSM, transaction formats, fee policy, formalization, and P2P v2.
The next Zcash Arborist Call is scheduled for September 17, 2026, at 15:00 UTC.