Anthropic audits Zcash protocol — no serious bugs found. Ironwood spec finalized. Zebra forces upgrade before NU7.
Archive note: this edition uses the current ZecBlock name and links. Reporting and publication dates are unchanged.
Top Stories
Two weeks after Taylor Hornby's discovery of the Orchard counterfeiting vulnerability, Shielded Labs worked with Anthropic to review the Zcash protocol using Mythos, with prompts provided by Taylor (@earthrise). No serious vulnerabilities identified. More details on the review and findings coming in a future post. The protocol is now on firmer ground than it was before the bug was found. Zooko's tweet. [Forum #56183]
ZODL, working alongside Tachyon, Valar Group, ZF, and Shielded Labs, finalized consensus rule changes for Ironwood. The new pool uses the existing Orchard protocol with the corrected circuit, disables Orchard bundles in coinbases, and implements a turnstile mechanism for supply verification. Old pool freezes to new outputs; existing funds exit through the turnstile. Activation targeted for late July, following zcashd end-of-support. [Forum #56044]
ZF released Zebra v5.1.0 (June 11) and v5.1.1 (June 12) in rapid succession. The key change: end-of-support window reduced from 105 to 44 days. With NU7 expected in late July, any node still running older versions will auto-shutdown before activation. This is a forcing function — upgrade now. [GitHub v5.1.1] [Forum #56152]
Ecosystem
Cancún, October 27–29 — Zcash's 10th birthday. In-person only, free ticket, travel on you. Scholarship applications (up to $1,000 + 4 nights lodging) close June 29. [ZF announcement]
Emersonian launched a signed key-value store built entirely on shielded memos. Use cases: price oracles, feature flags, release announcements — no centralized server, no IP leaks. Born from the Rome Dev Summit hackathon. zec.rocks/zkv [Forum #56066]
Another live merchant using shielded payments in production. [Tweet]
Paul Brigner (ZODL's Chief Policy Officer) launched Pretty Good Policy for Zcash. DC-based initiative focused on practical compliance frameworks for privacy-preserving digital cash. [Forum #56111]
Forum user topcrypto unveiled a desktop wallet built with librustzcash by a developer who learned Rust specifically for this. Working prototype demonstrated. [Forum #56164]
Swap, lend, borrow, and earn via RHEA Finance X Chain. ZCG confirmed grant support for the Noir extension wallet.
Recording station live at the Neocypherpunk Summit (Web3Privacy Now), DappCon, and The Blockspäti. [Forum #56173]
Shielded Labs extended Taylor's security consultant agreement through year-end — continuing vulnerability research and remediation support. Jason McGee's announcement.
Governance & Grants
Fourteen candidates competing for two open seats (Decentralistdan and GGuy terms expiring). ZCAP voting opened June 11. Notable candidates include Paul Brigner (ZODL policy), Valens (security researcher), and GGuy (incumbent). [Forum #56102]
"Should we change how we use the Dev Fund?" — with ZEC's price up roughly 9× since the last structure conversation, ZCG's 8% allocation sits at ~$24M/year. This is a reallocation discussion, not an elimination one. Thread is active. [Forum #56121]
Under Review:
Approved:
Protocol & Development
zcash_client_backend — 0.22.0 → 0.23.0pczt — 0.6.0 → 0.7.0 (first release since April)zcash_proofs — 0.27.0 → 0.28.0Non-trivial bumps. Any project using PCZT transaction flows or proof generation needs to audit dependencies.
Sean Bowe (ebfull) reported that protocol devs from across all orgs met twice this week to discuss specification and implementation progress. Tweet.
Shielded Labs posted a workshop summary with recording — Crosslink remains an active research track for long-term scaling. [Forum #55210]
Tweets of the Week
"Thanks, Anthropic, for helping protect Zcash users. At Shielded Labs's request, they ran a security audit of Zcash with Mythos. It did not find any more serious bugs in the Zcash protocol."
"Quick update on the last ~48 hours of Zcash Ironwood! Protocol devs from across all the orgs met twice to discuss specification and implementation progress."
"The case for Zcash is so simple. Do you really think the only credible and actually private financial asset in the world isn't going to be at least somewhat needed moving forward? Especially in a world of 24/7 AI surveillance? It's really not that complicated."
Forum Highlights
(#56121) — The most politically charged forum discussion of the month. Multiple viewpoints: some argue the Dev Fund should end by 2028, others push back with pro-continuation arguments. With ZCG's budget now worth ~$24M/year, the stakes are real.
(#56106) — One of the most-engaged community threads recently. the_zero sparked a philosophical discussion on privacy, respect, and the role of technology — with Supercut, Jenkin, and others contributing substantive replies. Rare depth for a crypto forum.
(#56109) — The Zcash forum moderator in Mindanao was affected by an earthquake. Community rallied with ZEC donations — a concrete example of private digital cash moving quickly for disaster relief.
Dre_Nesthub reported successfully syncing a Zcash node (Zebra 5.1.1) for a developer workshop in Nigeria. Grassroots node deployment continues in Africa.
Privacy Corner
Ironwood will ask every Orchard user to migrate their funds from the old pool to the new one. This migration is necessary — it's how the network proves the integrity of its supply. But it comes with a privacy tradeoff worth understanding.
When you move funds through the turnstile, two things become visible: the amount transferred and the approximate timing. An observer can see that X ZEC left the old Orchard pool and Y ZEC entered the new one within a certain window. If you're the only person migrating at 3am on a Tuesday, the link between your old and new pool activity becomes trivially obvious.
This is the cost of provable supply integrity. The protocol can either hide amounts perfectly forever (at the cost of undetectable counterfeiting risk) or it can periodically verify that no counterfeit coins exist (at the cost of revealing migration amounts). Ironwood chooses the latter — and it's the right choice.
What you can do: migrate when others are migrating. Don't rush. If your wallet supports batched or delayed migration, use it. The larger the crowd moving at the same time, the smaller your individual signal. This is the same principle that makes the shielded pool work in the first place — your privacy is proportional to the crowd you blend into.
Network Snapshot
ZEC Price
$423.14 · +2.7%
Market Cap
$7.09B · —
24h Volume
$362.2M · —
Block Height
3,377,929 · +1,143
Network Upgrade
NU6.2 (Zebra 5.1.1) · —
Chain Size
256.5 GB · —
Zcash Privacy Index
Powered by ZecBlock — live data from the Zcash blockchain.
Privacy Score
29 · 30
Shielded Pool
4,371,089 ZEC · 4,846,257 ZEC
Shielded % (Daily TX)
42.5% · 37.1%
Orchard Pool
3,714,553 ZEC · —
Sapling Pool
631,127 ZEC · —
Privacy Score
29 · 30
Shielded Pool
4,371,089 ZEC · 4,846,257 ZEC
Shielded % (Daily TX)
42.5% · 37.1%
Orchard Pool
3,714,553 ZEC · —
Sapling Pool
631,127 ZEC · —
Inflows
Ethereum ($530K), BNB Chain ($387K), Tron ($105K)
Outflows
Tron, Ethereum, Solana
24h Volume
$2.25M across 455 swaps
Active Nodes
341 (-41.6% WoW)
Countries
39
Tor Nodes
35
Top Country
United States (123 nodes)
The shielded pool dropped 475K ZEC this week — largely explained by Ironwood preparation deshielding, not panic selling. Our analysis of a 285K ZEC deshield on June 10 showed 96.5% sitting at transparent addresses, unmoved. Meanwhile, daily shielded transaction percentage jumped 5.4 points — active users continue to prefer shielded. The steep node count drop is tied to the Zebra v5.1.1 upgrade cycle — operators on deprecated versions getting auto-shutdown.
Tool Updates
ZecBlock
Published post-NU6.2 deshield analysis: 285K ZEC deshielded on June 10, 96.5% still sitting at transparent addresses untouched. Turnstile Tracker now the go-to dashboard for monitoring pool migration flows ahead of Ironwood.
What's Ahead