The Zcash Arborist Calls are bi-weekly protocol development meetings focused on tracking upcoming protocol deployment logistics, consensus node implementation issues, and protocol research.
This summary focuses on the last call that took place on 01/08/2026
While the holidays slowed merges, several PRs are now close to landing.
Key focus has been advancing shielded coinbase mining support (ZIP-213), bringing Zebra closer to feature parity with zcashd on regtest and custom testnets.
Mining & RPC improvements
Zebra has added pre Canopy block subsidy support to the getblocksubsidy RPC and Sapling commitment trees to getblocktemplate.
This unlocks mining pre Canopy blocks on regtest & custom testnets previously limited to post-NU5 blocks.
Infra, observability & alignment
Additional work includes another NSM PR review round, new Prometheus & Grafana metrics, and OpenTelemetry tracing support.
Zebra is also adding OpenRPC for a PoC unifying Zebra, Zaino, and Zallet, plus ongoing refactors from external contributors.
Zaino is nearing its first full release, with only a few PRs left to review and one final piece of work remaining. Once completed, it will fully support Zallet.
RPC development continues in parallel, and after months of being “almost there,” the project is clearly converging.
Work continues across ECC, ZF, and Zingo Labs to transition the ecosystem toward Zaino + Zebra. Recent progress builds on Zaino’s readiness and advances the broader move away from legacy components.
Light client protocol & LightwalletD
A key milestone is the adoption of the canonical Light Client Protocol files into Zaino.
What started as a small change grew into a substantial, structured PR, alongside new documentation for contributors marking a new phase in the LightwalletD deprecation effort.
Ecosystem feedback & readiness
The transition is now attracting real world feedback from miners, exchanges, and API providers, including questions around RPC placement between Zaino and Zebra.
This feedback is welcomed and signals growing ecosystem engagement ahead of deprecation.
- Nearing completion of its Orchard PR review, addressing detailed feedback through a series of smaller, focused PRs. Several changes are already merged, with the remaining work close to being finalized before handing things back upstream.
librustzcash follow-ups
- Changes in Orchard required follow-up updates in librustzcash. Qedit has prepared these updates in advance, ensuring they’re ready once upstream review begins, helping reduce friction across dependent repositories.
Test vectors & Python reference implementation
- Qedit has updated the Zcash test vectors and Python reference implementation, syncing with upstream changes and integrating ZIP-233 amount support. ZSA-specific logic has been cleanly separated from general improvements, with initial upstream PRs already opened.
ZIP-233 testing & infra
- Enabling ZIP-233 surfaced compilation gaps, now resolved by extending CI to explicitly test ZIP-233 paths. Additional work included minor ZIP cleanups, Zebra transaction tooling improvements and better performance on single node testnets.
Following audit feedback from Least Authority, updates were made to ZIP-233 adding formal requirements and privacy implications, now pending ZIP editor review.
On the engineering side, refreshed ZIP-234 and ZIP-235 PRs have been rebased and are awaiting merge into Zebra, moving NSM closer to implementation.
Milestone & staking mechanics
- The next milestone is targeted for Jan 28, focusing on core staking mechanics. This includes time and amount quantized staking, designed to balance privacy, security, and economic incentives.
Wallet prototypes & collaboration
- In parallel, work continues on two prototype wallet implementations, with ongoing collaboration alongside Zingo on a demo wallet. These prototypes help validate Crosslink assumptions from a user and integration perspective.
Security review & roadmap
A mechanism design security review is underway, complementing existing security proofs and focusing on the new PoS components.
The plan is to conclude the prototype design phase this quarter, assess community support, and if aligned move toward production design and Zebra integration.
During the open floor, Zooko highlighted new benchmarking & profiling documentation created by Marek while profiling Zebra capturing practical methods and workflows for future reference.
- Doc link: https://t.co/MciJ7pI5Ym