zcash_voting 0.2.3

Client-side library for Zcash shielded voting: ZKP delegation and vote-commitment proofs (Halo 2), ElGamal encryption, governance PCZT construction, Merkle witness generation, and SQLite round-state persistence.
Documentation

zcash_voting

Client-side library for integrating Zcash shielded voting into a wallet. Wraps the Halo 2 ZKPs, hotkey derivation, share construction, and governance-PCZT assembly that a wallet needs to participate in an on-chain voting round.

Usage

Wallets typically consume this through a language bridge:

  • Rust wallets: add zcash_voting = "0.1" to Cargo.toml.
  • iOS wallets: depend on valargroup/zcash-swift-wallet-sdk branch shielded-vote, which bundles this crate.

See the wallet integration guide for the full flow.

Crate layout

Crate Purpose
zcash_voting (this crate) Top-level API: proof generation, hotkey derivation, share construction, PCZT assembly, round-state storage.
vote-commitment-tree Append-only Poseidon Merkle tree for VANs and vote commitments.
vote-commitment-tree-client HTTP client + CLI for syncing the vote commitment tree from a running chain node.

Dependency notes

zcash_voting tracks the upstream Zcash crates directly:

  • orchard 0.13 — upstream zcash/orchard, pinned via a [patch.crates-io] redirect to the valargroup/orchard valar/0.13-spend-auth-g branch (tracked by valargroup/orchard PR #19). That branch carries orchard 0.13.0 plus the unstable-voting-circuits feature gate that exposes the governance-visibility APIs, plus cherry-picks of zcash/orchard #489 (SpendAuthG fixed-base multiplication) and zcash/orchard #495 (NoteValue::ZERO public associated constant). Once both upstream PRs land and an orchard 0.14 ships, this pin will collapse to the published crate.
  • pczt, zcash_keys, zcash_primitives, zcash_protocol, zcash_address, zcash_encoding, zcash_transparent — pinned to a recent commit of upstream zcash/librustzcash main. The previous valargroup/librustzcash fork (with shielded-voting getters in PCZT and friends) has been fully retired now that the relevant PRs (#2281, #2283, #2284) have all merged upstream.

License

Dual-licensed under MIT or Apache-2.0. See LICENSE-MIT and LICENSE-APACHE.