From ede3e58a393afd19bdcae3beca555fdae1bcf2cc Mon Sep 17 00:00:00 2001
From: Antoine Serval <k6nb4k@gmail.com>
Date: Tue, 14 Apr 2026 07:27:36 +0200
Subject: [PATCH] feat: add Zcash chain support with PCZT signing and unified
 addresses

Add Zcash as the first privacy-preserving chain in OWS, with full
shielded transaction support via the PCZT format.

Chain registration:
- ChainType::Zcash with CAIP-2 namespace, coin type 133
- Default lightwalletd endpoints (zec.rocks mainnet/testnet)

Wallet creation (ows wallet create):
- ZIP-32 key derivation from BIP-39 seed (needs_raw_seed trait extension)
- Unified address with Orchard + Sapling receivers, shielded by default

PCZT signing (ows sign tx --chain zcash):
- Orchard spend authorization (RedPallas)
- Sapling spend authorization (Jubjub)
- Transparent spend authorization (secp256k1)
- Skips non-matching/dummy actions per standard Orchard builder behavior
- Key material zeroized after use

Sign + broadcast (ows sign send-tx --chain zcash):
- PCZT finalization via TransactionExtractor
- Broadcast via lightwalletd gRPC with TLS

Feature-gated behind zcash-shielded (enabled by default in CLI).
Without the feature, falls back to transparent-only t-address support.

Dependencies: zcash_keys, pczt, orchard, sapling-crypto, zcash_transparent,
zcash_protocol, zcash_primitives (all from librustzcash, maintained by ZODL).

Tests: 27 Zcash-specific tests (15 signer unit tests + 12 library
integration tests). All 465 workspace tests pass.

Docs: zcash-guide.md covering wallet creation, PCZT pipeline, security
model, configuration, and end-to-end workflow.
---
 CONTRIBUTING.md                               |   24 +-
 docs/07-supported-chains.md                   |   10 +-
 docs/zcash-guide.md                           |  197 +++
 ows/Cargo.lock                                | 1199 ++++++++++++++++-
 ows/crates/ows-cli/Cargo.toml                 |    4 +
 ows/crates/ows-cli/src/commands/derive.rs     |   36 +-
 .../ows-cli/src/commands/send_transaction.rs  |   35 +-
 .../ows-cli/src/commands/sign_message.rs      |   10 +-
 .../ows-cli/src/commands/sign_transaction.rs  |    8 +
 ows/crates/ows-core/src/chain.rs              |   20 +-
 ows/crates/ows-core/src/config.rs             |   10 +-
 ows/crates/ows-lib/Cargo.toml                 |    3 +
 ows/crates/ows-lib/src/lib.rs                 |    2 +
 ows/crates/ows-lib/src/lwd_grpc.rs            |   84 ++
 ows/crates/ows-lib/src/ops.rs                 |  381 +++++-
 ows/crates/ows-signer/Cargo.toml              |   10 +
 ows/crates/ows-signer/src/chains/mod.rs       |    3 +
 ows/crates/ows-signer/src/chains/zcash.rs     |  648 +++++++++
 ows/crates/ows-signer/src/traits.rs           |   26 +
 19 files changed, 2630 insertions(+), 80 deletions(-)
 create mode 100644 docs/zcash-guide.md
 create mode 100644 ows/crates/ows-lib/src/lwd_grpc.rs
 create mode 100644 ows/crates/ows-signer/src/chains/zcash.rs

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index a433076a..5b37c3e0 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -30,13 +30,35 @@ cd bindings/python && maturin develop --release
 ### Running Tests
 
 ```bash
-# Rust tests
+# Rust tests (all features, including Zcash shielded support)
+cd ows && cargo test --workspace --features zcash-shielded
+
+# Rust tests (without Zcash shielded — faster, smaller dependency tree)
 cd ows && cargo test --workspace
 
 # Node tests
 cd bindings/node && npm test
 ```
 
+### Zcash Development
+
+Zcash shielded support (`zcash-shielded` feature) is enabled by default in the CLI but optional in the library crates. When developing Zcash-specific code:
+
+```bash
+# Build with Zcash shielded support
+cd ows && cargo build --workspace --features zcash-shielded
+
+# Run only Zcash tests
+cd ows && cargo test --features zcash-shielded -- zcash
+
+# Clippy with Zcash features
+cd ows && cargo clippy --workspace --features zcash-shielded -- -D warnings
+```
+
+The `zcash-shielded` feature adds dependencies on `zcash_keys`, `pczt`, `orchard`, and `sapling-crypto` from the [librustzcash](https://github.com/zcash/librustzcash) ecosystem. These are heavier than the base OWS dependencies — expect longer initial compile times.
+
+See [docs/zcash-guide.md](docs/zcash-guide.md) for architecture and usage details.
+
 ### Code Formatting
 
 ```bash
diff --git a/docs/07-supported-chains.md b/docs/07-supported-chains.md
index 6a2961d6..a66ed9b6 100644
--- a/docs/07-supported-chains.md
+++ b/docs/07-supported-chains.md
@@ -21,7 +21,7 @@ type AssetId = `${ChainId}:${string}`;
 // e.g. "eip155:8453:native" (ETH on Base)
 ```
 
-The `native` token refers to the chain's native currency (ETH, SOL, SUI, BTC, ATOM, TRX, TON, etc.).
+The `native` token refers to the chain's native currency (ETH, SOL, SUI, BTC, ATOM, TRX, TON, ZEC, etc.).
 
 ## Chain Families
 
@@ -38,6 +38,7 @@ OWS groups chains into families that share a cryptographic curve and address der
 | Sui | ed25519 | 784 | `m/44'/784'/{index}'/0'/0'` | `0x` + BLAKE2b-256 hex (32 bytes) | `sui` |
 | Spark | secp256k1 | 8797555 | `m/84'/0'/0'/0/{index}` | `spark:` + compressed pubkey hex | `spark` |
 | Filecoin | secp256k1 | 461 | `m/44'/461'/0'/0/{index}` | `f1` + base32(blake2b-160) | `fil` |
+| Zcash | secp256k1 / ZIP-32 | 133 | ZIP-32 (from raw seed) | Unified address (`u1...`) | `zcash` |
 
 ## Known Networks
 
@@ -67,6 +68,7 @@ Each network has a canonical chain identifier. Endpoint discovery and transport
 | Sui | `sui:mainnet` |
 | Spark | `spark:mainnet` |
 | Filecoin | `fil:mainnet` |
+| Zcash | `zcash:mainnet` |
 
 Implementations MAY ship convenience endpoint defaults, but those defaults are deployment choices rather than OWS interoperability requirements.
 
@@ -90,6 +92,7 @@ ton       → ton:mainnet
 sui       → sui:mainnet
 spark     → spark:mainnet
 filecoin  → fil:mainnet
+zcash     → zcash:mainnet
 ```
 
 Aliases MUST be resolved to full CAIP-2 identifiers before any processing. They MUST NOT appear in wallet files, policy files, or audit logs.
@@ -112,11 +115,14 @@ Master Seed (512 bits via PBKDF2)
     ├── m/44'/607'/0'       → TON Account 0
     ├── m/44'/784'/0'/0'/0' → Sui Account 0
     ├── m/84'/0'/0'/0/0     → Spark Account 0
-    └── m/44'/461'/0'/0/0   → Filecoin Account 0
+    ├── m/44'/461'/0'/0/0   → Filecoin Account 0
+    └── ZIP-32(seed, 0)     → Zcash Account 0 (unified address)
 ```
 
 A single mnemonic derives accounts across all supported chains. The wallet file stores the encrypted mnemonic; the signer derives the appropriate private key using each chain's coin type and derivation path.
 
+> **Note on Zcash:** Zcash unified addresses use ZIP-32 derivation, which operates on the raw BIP-39 seed rather than a BIP-32 derived key. The signer signals this via `needs_raw_seed() → true`, and the wallet layer passes the full 64-byte seed instead of a 32-byte derived key. See [Zcash Integration Guide](zcash-guide.md) for details.
+
 ## Adding a New Chain
 
 1. Define a canonical chain identifier, preferably using CAIP-2.
diff --git a/docs/zcash-guide.md b/docs/zcash-guide.md
new file mode 100644
index 00000000..a0e98b6c
--- /dev/null
+++ b/docs/zcash-guide.md
@@ -0,0 +1,197 @@
+# Zcash Integration Guide
+
+Zcash is the first privacy-preserving chain in OWS. It supports shielded transactions via the PCZT (Partially Created Zcash Transaction) format, giving agents and wallets a way to hold and spend ZEC without exposing transaction metadata.
+
+## How Zcash differs from other OWS chains
+
+Every other chain in OWS follows the same pattern: derive a key via BIP-44, hash and sign a transaction, broadcast via JSON-RPC. Zcash breaks this pattern in two ways:
+
+1. **Key derivation uses ZIP-32, not BIP-44.** Zcash unified addresses contain Orchard and Sapling receivers, which require the raw BIP-39 seed passed through the ZIP-32 derivation scheme — not a BIP-32 derived private key.
+
+2. **Signing operates on PCZTs, not raw transactions.** Zcash shielded transactions require zero-knowledge proofs and per-pool spend authorization signatures (RedPallas for Orchard, Jubjub for Sapling). OWS handles only the signing step. The ZK proof generation happens externally.
+
+## Wallet creation
+
+```bash
+ows wallet create --name my-wallet
+```
+
+Zcash appears alongside all other chains. The derived address is a unified address (`u1...`) with Orchard and Sapling receivers — shielded by default.
+
+```
+eip155:1    → 0xab16a96D359eC26a11e2C2b3d8f8B8942d5Bfcdb
+solana:...  → 7v91N7iZ9mNicL8WfG6cgSCKyRXydQjLh6UYBWwm6y1Q
+zcash:mainnet → u1qxnwj8h...
+```
+
+Under the hood, OWS detects that the Zcash signer requires the raw seed (`needs_raw_seed() → true`) and passes the full 64-byte BIP-39 seed through ZIP-32 derivation instead of BIP-44:
+
+```
+BIP-39 Mnemonic
+    │
+    ▼
+Raw Seed (64 bytes)
+    │
+    ├── BIP-44 path  → EVM, Solana, Bitcoin, ...
+    │
+    └── ZIP-32       → Unified Spending Key
+                          │
+                          ├── Orchard receiver
+                          ├── Sapling receiver
+                          └── Unified Address (u1...)
+```
+
+## Address derivation
+
+To derive a Zcash address from an existing mnemonic:
+
+```bash
+echo "your twelve word mnemonic ..." | ows derive --chain zcash
+```
+
+This returns a unified address. To derive all chains at once:
+
+```bash
+echo "your twelve word mnemonic ..." | ows derive
+```
+
+## Signing a PCZT
+
+### The PCZT pipeline
+
+Zcash transactions are built collaboratively using the PCZT format. The roles are:
+
+```
+Creator      →  Builds the transaction structure (inputs, outputs, amounts)
+    │
+Prover       →  Generates zero-knowledge proofs (Sapling, Orchard)
+    │
+Signer (OWS) →  Applies spend authorization signatures
+    │
+Finalizer    →  Extracts the signed transaction
+    │
+Broadcaster  →  Sends to the network via lightwalletd
+```
+
+OWS fills the **Signer** role. It receives a PCZT that already has ZK proofs applied, decrypts the spending key from the vault, signs the relevant inputs, and returns the signed PCZT.
+
+### CLI usage
+
+```bash
+# Sign a PCZT (hex-encoded)
+ows sign tx --chain zcash --wallet my-wallet --tx <pczt_hex>
+```
+
+The `<pczt_hex>` must be a serialized PCZT that has already been through the Creator and Prover stages. Tools that produce PCZTs include:
+
+- **zipher-cli** (`zipher create-pczt`)
+- **Zodl** (the Zcash reference wallet, via `zcash_client_backend`)
+- Any tool using `zcash_client_backend::data_api::wallet::create_pczt_from_proposal`
+
+The output is the signed PCZT in hex. The caller is responsible for finalization and broadcast.
+
+### Security: trusting the PCZT source
+
+OWS signs whatever PCZT is passed to it — the same trust model as every other chain. When you call `ows sign tx --chain evm`, OWS signs the unsigned EVM transaction without inspecting whether the recipient or amount is what you intended. The caller (your agent, your CLI, your wallet) is responsible for constructing a safe transaction.
+
+For Zcash, this means: if a malicious PCZT is constructed to send your funds to an attacker's address, OWS will sign it. The PCZT format does carry metadata (amounts, recipients, memos) that a higher-level application could inspect before requesting a signature, but OWS itself operates at the signing primitive level — it does not enforce spending policies at the PCZT layer.
+
+This is consistent with the OWS security model: the vault holds keys, the signer signs, and the policy engine (if configured) enforces spending limits. Transaction construction and validation are the caller's responsibility across all chains.
+
+### Sign and broadcast
+
+For end-to-end sending:
+
+```bash
+ows sign send-tx --chain zcash --wallet my-wallet --tx <pczt_hex>
+```
+
+This signs the PCZT, extracts the finalized transaction, and broadcasts it to lightwalletd via gRPC. The default endpoint is `zec.rocks:443` for mainnet.
+
+Returns the transaction ID (txid) on success.
+
+## What OWS signs
+
+When `sign tx --chain zcash` is called, OWS:
+
+1. Decrypts the BIP-39 mnemonic from the vault
+2. Derives the Unified Spending Key via ZIP-32
+3. Extracts per-pool signing keys:
+   - **Orchard:** `SpendAuthorizingKey` (RedPallas)
+   - **Sapling:** `ask` (Jubjub)
+   - **Transparent:** secp256k1 secret key
+4. Iterates over PCZT inputs and signs those matching the derived keys
+5. Skips dummy/padding actions (standard Orchard behavior)
+6. Returns the signed PCZT
+
+The spending key is zeroized after use.
+
+## Configuration
+
+### Default RPC endpoints
+
+| Network | Endpoint |
+|---------|----------|
+| `zcash:mainnet` | `https://zec.rocks:443` |
+| `zcash:testnet` | `https://testnet.zec.rocks:443` |
+
+Override via `~/.ows/config.toml`:
+
+```toml
+[rpc]
+"zcash:mainnet" = "https://your-lightwalletd:443"
+```
+
+Or pass `--rpc-url` on the CLI.
+
+### Feature flag
+
+Zcash shielded support requires the `zcash-shielded` feature flag, which is enabled by default in the CLI. The feature adds dependencies on `zcash_keys`, `pczt`, `orchard`, and `sapling-crypto` for ZIP-32 derivation and PCZT signing.
+
+Without `zcash-shielded`, Zcash falls back to transparent-only support (t-addresses, secp256k1 signing).
+
+## Dependencies
+
+| Crate | Purpose |
+|-------|---------|
+| `zcash_keys` 0.12 | ZIP-32 key derivation, unified address encoding |
+| `zcash_protocol` 0.7 | Network parameters (mainnet/testnet) |
+| `zip32` 0.2 | Account ID types |
+| `pczt` 0.5 | PCZT parsing, Signer role |
+| `orchard` 0.11 | Orchard spend authorization key types |
+| `sapling-crypto` 0.5 | Sapling spend auth key (`ask`) |
+| `zcash_transparent` 0.6 | Transparent key derivation |
+| `zcash_primitives` 0.26 | Transaction serialization (for broadcast) |
+
+All crates are from the official [librustzcash](https://github.com/zcash/librustzcash) ecosystem, originally built by Electric Coin Company and now maintained by [ZODL](https://zodl.com) (Zcash Open Development Lab).
+
+## End-to-end example
+
+A complete shielded send using OWS and zipher-cli:
+
+```bash
+# 1. Create an OWS wallet
+ows wallet create --name agent-wallet
+
+# 2. Fund the Zcash address (send ZEC to the u1... address)
+
+# 3. Build a PCZT with zipher-cli (Creator + Prover)
+PCZT=$(zipher create-pczt \
+  --to u1recipient... \
+  --amount 0.01 \
+  --data-dir ~/.zipher)
+
+# 4. Sign with OWS (Signer)
+ows sign send-tx --chain zcash --wallet agent-wallet --tx $PCZT
+
+# 5. Transaction is broadcast and visible on a block explorer
+```
+
+## References
+
+- [ZIP-32: Shielded Hierarchical Deterministic Wallets](https://zips.z.cash/zip-0032)
+- [ZIP-316: Unified Addresses](https://zips.z.cash/zip-0316)
+- [ZIP-244: Transaction Identifier and Commitment](https://zips.z.cash/zip-0244)
+- [PCZT specification](https://github.com/zcash/zips/pull/766)
+- [OWS Signing Interface](02-signing-interface.md)
+- [OWS Supported Chains](07-supported-chains.md)
diff --git a/ows/Cargo.lock b/ows/Cargo.lock
index 947d481c..27fae1b9 100644
--- a/ows/Cargo.lock
+++ b/ows/Cargo.lock
@@ -8,7 +8,7 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d122413f284cf2d62fb1b7db97e02edb8cda96d769b16e443a4f6195e35662b0"
 dependencies = [
- "crypto-common",
+ "crypto-common 0.1.7",
  "generic-array",
 ]
 
@@ -102,6 +102,18 @@ version = "1.0.102"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
+[[package]]
+name = "arrayref"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76a2e8124351fda1ef8aaaa3bbd7ebbcb486bbcd4225aca0aa0d84bb2db8fecb"
+
+[[package]]
+name = "arrayvec"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7c02d123df017efcdfbd739ef81735b36c5ba83ec3c59c80a9d7ecc718f92e50"
+
 [[package]]
 name = "async-stream"
 version = "0.3.6"
@@ -230,6 +242,43 @@ version = "0.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32637268377fc7b10a8c6d51de3e7fba1ce5dd371a96e342b34e6078db558e7f"
 
+[[package]]
+name = "bellman"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9afceed28bac7f9f5a508bca8aeeff51cdfa4770c0b967ac55c621e2ddfd6171"
+dependencies = [
+ "bitvec",
+ "blake2s_simd",
+ "byteorder",
+ "crossbeam-channel",
+ "ff",
+ "group",
+ "lazy_static",
+ "log",
+ "num_cpus",
+ "pairing",
+ "rand_core 0.6.4",
+ "rayon",
+ "subtle",
+]
+
+[[package]]
+name = "bip32"
+version = "0.6.0-pre.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "143f5327f23168716be068f8e1014ba2ea16a6c91e8777bc8927da7b51e1df1f"
+dependencies = [
+ "bs58",
+ "hmac 0.13.0-pre.4",
+ "rand_core 0.6.4",
+ "ripemd 0.2.0-pre.4",
+ "secp256k1",
+ "sha2 0.11.0-pre.4",
+ "subtle",
+ "zeroize",
+]
+
 [[package]]
 name = "bitflags"
 version = "2.11.0"
@@ -254,7 +303,29 @@ version = "0.10.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "46502ad458c9a52b69d4d4d32775c788b7a1b85e8bc9d482d92250fc0e3f8efe"
 dependencies = [
- "digest",
+ "digest 0.10.7",
+]
+
+[[package]]
+name = "blake2b_simd"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b79834656f71332577234b50bfc009996f7449e0c056884e6a02492ded0ca2f3"
+dependencies = [
+ "arrayref",
+ "arrayvec",
+ "constant_time_eq",
+]
+
+[[package]]
+name = "blake2s_simd"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee29928bad1e3f94c9d1528da29e07a1d3d04817ae8332de1e8b846c8439f4b3"
+dependencies = [
+ "arrayref",
+ "arrayvec",
+ "constant_time_eq",
 ]
 
 [[package]]
@@ -266,13 +337,44 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "block-buffer"
+version = "0.11.0-rc.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fd016a0ddc7cb13661bf5576073ce07330a693f8608a1320b4e20561cc12cdc"
+dependencies = [
+ "hybrid-array",
+]
+
+[[package]]
+name = "bls12_381"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7bc6d6292be3a19e6379786dac800f551e5865a5bb51ebbe3064ab80433f403"
+dependencies = [
+ "ff",
+ "group",
+ "pairing",
+ "rand_core 0.6.4",
+ "subtle",
+]
+
+[[package]]
+name = "bounded-vec"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09dc0086e469182132244e9b8d313a0742e1132da43a08c24b9dd3c18e0faf3a"
+dependencies = [
+ "thiserror 2.0.18",
+]
+
 [[package]]
 name = "bs58"
 version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bf88ba1141d185c399bee5288d850d63b8369520c1eafc32a0430b5b6c287bf4"
 dependencies = [
- "sha2",
+ "sha2 0.10.9",
  "tinyvec",
 ]
 
@@ -282,12 +384,27 @@ version = "3.20.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
 
+[[package]]
+name = "byteorder"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
+
 [[package]]
 name = "bytes"
 version = "1.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1e748733b7cbc798e1434b6ac524f0c1ff2ab456fe201501e6497c8417a4fc33"
 
+[[package]]
+name = "cbc"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26b52a9543ae338f279b96b0b9fed9c8093744685043739079ce85cd58f289a6"
+dependencies = [
+ "cipher",
+]
+
 [[package]]
 name = "cc"
 version = "1.2.57"
@@ -310,6 +427,30 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "613afe47fcd5fac7ccf1db93babcb082c5994d996f20b8b159f2ad1658eb5724"
 
+[[package]]
+name = "chacha20"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3613f74bd2eac03dad61bd53dbe620703d4371614fe0bc3b9f04dd36fe4e818"
+dependencies = [
+ "cfg-if",
+ "cipher",
+ "cpufeatures",
+]
+
+[[package]]
+name = "chacha20poly1305"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "10cd79432192d1c0f4e1a0fef9527696cc039165d729fb41b3f4f4f354c2dc35"
+dependencies = [
+ "aead",
+ "chacha20",
+ "cipher",
+ "poly1305",
+ "zeroize",
+]
+
 [[package]]
 name = "chrono"
 version = "0.4.44"
@@ -330,8 +471,9 @@ version = "0.4.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "773f3b9af64447d2ce9850330c473515014aa235e6a783b02db81ff39e4a3dad"
 dependencies = [
- "crypto-common",
+ "crypto-common 0.1.7",
  "inout",
+ "zeroize",
 ]
 
 [[package]]
@@ -374,6 +516,15 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c8d4a3bb8b1e0c1050499d1815f5ab16d04f0959b233085fb31653fbfc9d98f9"
 
+[[package]]
+name = "cobs"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fa961b519f0b462e3a3b4a34b64d119eeaca1d59af726fe450bbba07a9fc0a1"
+dependencies = [
+ "thiserror 2.0.18",
+]
+
 [[package]]
 name = "coins-bip32"
 version = "0.11.1"
@@ -382,11 +533,11 @@ checksum = "66c43ff7fd9ff522219058808a259e61423335767b1071d5b346de60d9219657"
 dependencies = [
  "bs58",
  "coins-core",
- "digest",
- "hmac",
+ "digest 0.10.7",
+ "hmac 0.12.1",
  "k256",
  "serde",
- "sha2",
+ "sha2 0.10.9",
  "thiserror 1.0.69",
 ]
 
@@ -398,11 +549,11 @@ checksum = "4c4587c0b4064da887ed39a6522f577267d57e58bdd583178cd877d721b56a2e"
 dependencies = [
  "bitvec",
  "coins-bip32",
- "hmac",
+ "hmac 0.12.1",
  "once_cell",
  "pbkdf2",
  "rand 0.8.5",
- "sha2",
+ "sha2 0.10.9",
  "thiserror 1.0.69",
 ]
 
@@ -416,11 +567,11 @@ dependencies = [
  "bech32 0.9.1",
  "bs58",
  "const-hex",
- "digest",
+ "digest 0.10.7",
  "generic-array",
- "ripemd",
+ "ripemd 0.1.3",
  "serde",
- "sha2",
+ "sha2 0.10.9",
  "sha3",
  "thiserror 1.0.69",
 ]
@@ -449,12 +600,27 @@ version = "0.9.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c2459377285ad874054d797f3ccebf984978aa39129f6eafde5cdc8315b612f8"
 
+[[package]]
+name = "constant_time_eq"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d52eff69cd5e647efe296129160853a42795992097e8af39800e1060caeea9b"
+
 [[package]]
 name = "core-foundation-sys"
 version = "0.8.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"
 
+[[package]]
+name = "core2"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "239fa3ae9b63c2dc74bd3fa852d4792b8b305ae64eeede946265b6af62f1fff3"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "cpufeatures"
 version = "0.2.17"
@@ -464,6 +630,46 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "crossbeam-channel"
+version = "0.5.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "82b8f8f868b36967f9606790d1903570de9ceaf870a7bf9fbbd3016d636a2cb2"
+dependencies = [
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-deque"
+version = "0.8.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9dd111b7b7f7d55b72c0a6ae361660ee5853c9af73f70c3c2ef6858b950e2e51"
+dependencies = [
+ "crossbeam-epoch",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.9.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b82ac4a3c2ca9c3460964f020e1402edd5753411d7737aa39c3714ad1b5420e"
+dependencies = [
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.8.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
+
+[[package]]
+name = "crunchy"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "460fbee9c2c2f33933d720630a6a0bac33ba7053db5344fac858d4b8952d77d5"
+
 [[package]]
 name = "crypto-bigint"
 version = "0.5.5"
@@ -487,6 +693,15 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "crypto-common"
+version = "0.2.0-rc.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b0b8ce8218c97789f16356e7896b3714f26c2ee1079b79c0b7ae7064bb9089fa"
+dependencies = [
+ "hybrid-array",
+]
+
 [[package]]
 name = "ctr"
 version = "0.9.2"
@@ -505,7 +720,7 @@ dependencies = [
  "cfg-if",
  "cpufeatures",
  "curve25519-dalek-derive",
- "digest",
+ "digest 0.10.7",
  "fiat-crypto",
  "rustc_version",
  "subtle",
@@ -523,6 +738,40 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "darling"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25ae13da2f202d56bd7f91c25fba009e7717a1e4a1cc98a76d844b65ae912e9d"
+dependencies = [
+ "darling_core",
+ "darling_macro",
+]
+
+[[package]]
+name = "darling_core"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9865a50f7c335f53564bb694ef660825eb8610e0a53d3e11bf1b0d3df31e03b0"
+dependencies = [
+ "ident_case",
+ "proc-macro2",
+ "quote",
+ "strsim",
+ "syn",
+]
+
+[[package]]
+name = "darling_macro"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3984ec7bd6cfa798e62b4a642426a5be0e68f9401cfc2a01e3fa9ea2fcdb8d"
+dependencies = [
+ "darling_core",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "der"
 version = "0.7.10"
@@ -533,15 +782,35 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "deranged"
+version = "0.5.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7cd812cc2bc1d69d4764bd80df88b4317eaef9e773c75226407d9bc0876b211c"
+dependencies = [
+ "powerfmt",
+]
+
 [[package]]
 name = "digest"
 version = "0.10.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
 dependencies = [
- "block-buffer",
+ "block-buffer 0.10.4",
  "const-oid",
- "crypto-common",
+ "crypto-common 0.1.7",
+ "subtle",
+]
+
+[[package]]
+name = "digest"
+version = "0.11.0-pre.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cf2e3d6615d99707295a9673e889bf363a04b2a466bd320c65a72536f7577379"
+dependencies = [
+ "block-buffer 0.11.0-rc.3",
+ "crypto-common 0.2.0-rc.1",
  "subtle",
 ]
 
@@ -556,6 +825,15 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "document-features"
+version = "0.2.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4b8a88685455ed29a21542a33abd9cb6510b6b129abadabdcef0f4c55bc8f61"
+dependencies = [
+ "litrs",
+]
+
 [[package]]
 name = "ecdsa"
 version = "0.16.9"
@@ -563,7 +841,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ee27f32b5c5292967d2d4a9d7f1e0b0aed2c15daded5a60300e4abb9d8020bca"
 dependencies = [
  "der",
- "digest",
+ "digest 0.10.7",
  "elliptic-curve",
  "rfc6979",
  "signature",
@@ -589,7 +867,7 @@ dependencies = [
  "curve25519-dalek",
  "ed25519",
  "serde",
- "sha2",
+ "sha2 0.10.9",
  "subtle",
  "zeroize",
 ]
@@ -608,7 +886,7 @@ checksum = "b5e6043086bf7973472e0c7dff2142ea0b680d30e18d9cc40f267efbf222bd47"
 dependencies = [
  "base16ct",
  "crypto-bigint",
- "digest",
+ "digest 0.10.7",
  "ff",
  "generic-array",
  "group",
@@ -619,6 +897,28 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "embedded-io"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ef1a6892d9eef45c8fa6b9e0086428a2cca8491aca8f787c534a3d6d0bcb3ced"
+
+[[package]]
+name = "embedded-io"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "edd0f118536f44f5ccd48bcb8b111bdc3de888b58c74639dfb034a357d0f206d"
+
+[[package]]
+name = "equihash"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca4f333d4ccc9d23c06593733673026efa71a332e028b00f12cf427b9677dce9"
+dependencies = [
+ "blake2b_simd",
+ "core2",
+]
+
 [[package]]
 name = "equivalent"
 version = "1.0.2"
@@ -635,6 +935,15 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "f4jumble"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0d42773cb15447644d170be20231a3268600e0c4cea8987d013b93ac973d3cf7"
+dependencies = [
+ "blake2b_simd",
+]
+
 [[package]]
 name = "fastrand"
 version = "2.3.0"
@@ -647,6 +956,7 @@ version = "0.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c0b50bfb653653f9ca9095b427bed08ab8d75a137839d9ad64eb11810d5b6393"
 dependencies = [
+ "bitvec",
  "rand_core 0.6.4",
  "subtle",
 ]
@@ -684,6 +994,20 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "fpe"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26c4b37de5ae15812a764c958297cfc50f5c010438f60c6ce75d11b802abd404"
+dependencies = [
+ "cbc",
+ "cipher",
+ "libm",
+ "num-bigint",
+ "num-integer",
+ "num-traits",
+]
+
 [[package]]
 name = "funty"
 version = "2.0.0"
@@ -780,6 +1104,18 @@ dependencies = [
  "wasip3",
 ]
 
+[[package]]
+name = "getset"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9cf0fc11e47561d47397154977bc219f4cf809b2974facc3ccb3b89e2436f912"
+dependencies = [
+ "proc-macro-error2",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "ghash"
 version = "0.5.1"
@@ -797,6 +1133,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f0f9ef7462f7c099f518d754361858f86d8a07af53ba9af0fe635bbccb151a63"
 dependencies = [
  "ff",
+ "memuse",
  "rand_core 0.6.4",
  "subtle",
 ]
@@ -820,6 +1157,61 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "halo2_gadgets"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "73a5e510d58a07d8ed238a5a8a436fe6c2c79e1bb2611f62688bc65007b4e6e7"
+dependencies = [
+ "arrayvec",
+ "bitvec",
+ "ff",
+ "group",
+ "halo2_poseidon",
+ "halo2_proofs",
+ "lazy_static",
+ "pasta_curves",
+ "rand 0.8.5",
+ "sinsemilla",
+ "subtle",
+ "uint",
+]
+
+[[package]]
+name = "halo2_legacy_pdqsort"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47716fe1ae67969c5e0b2ef826f32db8c3be72be325e1aa3c1951d06b5575ec5"
+
+[[package]]
+name = "halo2_poseidon"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fa3da60b81f02f9b33ebc6252d766f843291fb4d2247a07ae73d20b791fc56f"
+dependencies = [
+ "bitvec",
+ "ff",
+ "group",
+ "pasta_curves",
+]
+
+[[package]]
+name = "halo2_proofs"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05713f117155643ce10975e0bee44a274bcda2f4bb5ef29a999ad67c1fa8d4d3"
+dependencies = [
+ "blake2b_simd",
+ "ff",
+ "group",
+ "halo2_legacy_pdqsort",
+ "indexmap 1.9.3",
+ "maybe-rayon",
+ "pasta_curves",
+ "rand_core 0.6.4",
+ "tracing",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.12.3"
@@ -847,6 +1239,12 @@ version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 
+[[package]]
+name = "hermit-abi"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc0fef456e4baa96da950455cd02c081ca953b141298e41db3fc7e36b1da849c"
+
 [[package]]
 name = "hex"
 version = "0.4.3"
@@ -859,7 +1257,7 @@ version = "0.12.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7b5f8eb2ad728638ea2c7d47a21db23b7b58a72ed6a38256b8a1849f15fbbdf7"
 dependencies = [
- "hmac",
+ "hmac 0.12.1",
 ]
 
 [[package]]
@@ -868,7 +1266,16 @@ version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6c49c37c09c17a53d937dfbb742eb3a961d65a994e6bcdcf37e7399d0cc8ab5e"
 dependencies = [
- "digest",
+ "digest 0.10.7",
+]
+
+[[package]]
+name = "hmac"
+version = "0.13.0-pre.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e4b1fb14e4df79f9406b434b60acef9f45c26c50062cccf1346c6103b8c47d58"
+dependencies = [
+ "digest 0.11.0-pre.9",
 ]
 
 [[package]]
@@ -916,6 +1323,15 @@ version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df3b46402a9d5adb4c86a0cf463f42e19994e3ee891101b1841f30a545cb49a9"
 
+[[package]]
+name = "hybrid-array"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2d35805454dc9f8662a98d6d61886ffe26bd465f5960e0e55345c70d5c0d2a9"
+dependencies = [
+ "typenum",
+]
+
 [[package]]
 name = "hyper"
 version = "1.8.1"
@@ -953,7 +1369,7 @@ dependencies = [
  "tokio",
  "tokio-rustls",
  "tower-service",
- "webpki-roots",
+ "webpki-roots 1.0.6",
 ]
 
 [[package]]
@@ -1103,6 +1519,12 @@ version = "2.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3d3067d79b975e8844ca9eb072e16b31c3c1c36928edf9c6789548c524d0d954"
 
+[[package]]
+name = "ident_case"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
+
 [[package]]
 name = "idna"
 version = "1.1.0"
@@ -1124,6 +1546,15 @@ dependencies = [
  "icu_properties",
 ]
 
+[[package]]
+name = "incrementalmerkletree"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "30821f91f0fa8660edca547918dc59812893b497d07c1144f326f07fdd94aba9"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "indexmap"
 version = "1.9.3"
@@ -1202,6 +1633,20 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "jubjub"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8499f7a74008aafbecb2a2e608a3e13e4dd3e84df198b604451efe93f2de6e61"
+dependencies = [
+ "bitvec",
+ "bls12_381",
+ "ff",
+ "group",
+ "rand_core 0.6.4",
+ "subtle",
+]
+
 [[package]]
 name = "k256"
 version = "0.13.4"
@@ -1212,7 +1657,7 @@ dependencies = [
  "ecdsa",
  "elliptic-curve",
  "once_cell",
- "sha2",
+ "sha2 0.10.9",
  "signature",
 ]
 
@@ -1225,6 +1670,15 @@ dependencies = [
  "cpufeatures",
 ]
 
+[[package]]
+name = "lazy_static"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
+dependencies = [
+ "spin",
+]
+
 [[package]]
 name = "leb128fmt"
 version = "0.1.0"
@@ -1237,6 +1691,12 @@ version = "0.2.183"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b5b646652bf6661599e1da8901b3b9522896f01e736bad5f723fe7a3a27f899d"
 
+[[package]]
+name = "libm"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6d2cec3eae94f9f509c767b45932f1ada8350c4bdb85af2fcab4a3c14807981"
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.12.1"
@@ -1249,6 +1709,12 @@ version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6373607a59f0be73a39b6fe456b8192fcc3585f602af20751600e974dd455e77"
 
+[[package]]
+name = "litrs"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "11d3d7f243d5c5a8b9bb5d6dd2b1602c0cb0b9db1621bafc7ed66e35ff9fe092"
+
 [[package]]
 name = "log"
 version = "0.4.29"
@@ -1267,12 +1733,28 @@ version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0e7465ac9959cc2b1404e8e2367b43684a6d13790fe23056cc8c6c5a6b7bcb94"
 
+[[package]]
+name = "maybe-rayon"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8ea1f30cedd69f0a2954655f7188c6a834246d2bcf1e315e2ac40c4b24dc9519"
+dependencies = [
+ "cfg-if",
+ "rayon",
+]
+
 [[package]]
 name = "memchr"
 version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
 
+[[package]]
+name = "memuse"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d97bbf43eb4f088f8ca469930cde17fa036207c9a5e02ccc5107c4e8b17c964"
+
 [[package]]
 name = "mime"
 version = "0.3.17"
@@ -1290,6 +1772,37 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "nonempty"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "549e471b99ccaf2f89101bec68f4d244457d5a95a9c3d0672e9564124397741d"
+
+[[package]]
+name = "num-bigint"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a5e44f723f1133c9deac646763579fdb3ac745e418f2a7af9cd0c431da1f20b9"
+dependencies = [
+ "num-integer",
+ "num-traits",
+]
+
+[[package]]
+name = "num-conv"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c6673768db2d862beb9b39a78fdcb1a69439615d5794a1be50caa9bc92c81967"
+
+[[package]]
+name = "num-integer"
+version = "0.1.46"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7969661fd2958a5cb096e56c8e1ad0444ac2bbcd0061bd28660485a44879858f"
+dependencies = [
+ "num-traits",
+]
+
 [[package]]
 name = "num-traits"
 version = "0.2.19"
@@ -1299,6 +1812,16 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "num_cpus"
+version = "1.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "91df4bbde75afed763b708b7eee1e8e7651e02d97f6d5dd763e89367e957b23b"
+dependencies = [
+ "hermit-abi",
+ "libc",
+]
+
 [[package]]
 name = "once_cell"
 version = "1.21.4"
@@ -1317,6 +1840,41 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c08d65885ee38876c4f86fa503fb49d7b507c2b62552df7c70b2fce627e06381"
 
+[[package]]
+name = "orchard"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1ef66fcf99348242a20d582d7434da381a867df8dc155b3a980eca767c56137"
+dependencies = [
+ "aes",
+ "bitvec",
+ "blake2b_simd",
+ "core2",
+ "ff",
+ "fpe",
+ "getset",
+ "group",
+ "halo2_gadgets",
+ "halo2_poseidon",
+ "halo2_proofs",
+ "hex",
+ "incrementalmerkletree",
+ "lazy_static",
+ "memuse",
+ "nonempty",
+ "pasta_curves",
+ "rand 0.8.5",
+ "reddsa",
+ "serde",
+ "sinsemilla",
+ "subtle",
+ "tracing",
+ "visibility",
+ "zcash_note_encryption",
+ "zcash_spec",
+ "zip32",
+]
+
 [[package]]
 name = "ows-cli"
 version = "1.0.0"
@@ -1362,17 +1920,19 @@ dependencies = [
  "k256",
  "ows-core",
  "ows-signer",
+ "pczt",
  "prost",
  "rand 0.8.5",
  "serde",
  "serde_json",
- "sha2",
+ "sha2 0.10.9",
  "sha3",
  "tempfile",
  "thiserror 2.0.18",
  "tokio",
  "tonic",
  "uuid",
+ "zcash_primitives",
  "zeroize",
 ]
 
@@ -1402,24 +1962,40 @@ dependencies = [
  "bs58",
  "coins-bip32",
  "coins-bip39",
- "digest",
+ "digest 0.10.7",
  "ed25519-dalek",
  "hex",
  "hkdf",
- "hmac",
+ "hmac 0.12.1",
  "k256",
  "libc",
+ "orchard",
  "ows-core",
+ "pczt",
  "rand 0.8.5",
- "ripemd",
+ "ripemd 0.1.3",
+ "sapling-crypto",
  "scrypt",
  "serde",
  "serde_json",
- "sha2",
+ "sha2 0.10.9",
  "sha3",
  "signal-hook",
  "thiserror 2.0.18",
+ "zcash_keys",
+ "zcash_protocol",
+ "zcash_transparent",
  "zeroize",
+ "zip32",
+]
+
+[[package]]
+name = "pairing"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "81fec4625e73cf41ef4bb6846cafa6d44736525f442ba45e407c4a000a13996f"
+dependencies = [
+ "group",
 ]
 
 [[package]]
@@ -1433,14 +2009,58 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "pasta_curves"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3e57598f73cc7e1b2ac63c79c517b31a0877cd7c402cdcaa311b5208de7a095"
+dependencies = [
+ "blake2b_simd",
+ "ff",
+ "group",
+ "lazy_static",
+ "rand 0.8.5",
+ "static_assertions",
+ "subtle",
+]
+
 [[package]]
 name = "pbkdf2"
 version = "0.12.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8ed6a7761f76e3b9f92dfb0a60a6a6477c61024b775147ff0973a02653abaf2"
 dependencies = [
- "digest",
- "hmac",
+ "digest 0.10.7",
+ "hmac 0.12.1",
+]
+
+[[package]]
+name = "pczt"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1ea1cd05607eee33d320860c8e1159e78770f1d1909748c72f53959e106c6899"
+dependencies = [
+ "blake2b_simd",
+ "bls12_381",
+ "document-features",
+ "ff",
+ "getset",
+ "jubjub",
+ "nonempty",
+ "orchard",
+ "pasta_curves",
+ "postcard",
+ "rand_core 0.6.4",
+ "redjubjub",
+ "sapling-crypto",
+ "secp256k1",
+ "serde",
+ "serde_with",
+ "zcash_note_encryption",
+ "zcash_primitives",
+ "zcash_protocol",
+ "zcash_script",
+ "zcash_transparent",
 ]
 
 [[package]]
@@ -1491,6 +2111,17 @@ dependencies = [
  "spki",
 ]
 
+[[package]]
+name = "poly1305"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8159bd90725d2df49889a078b54f4f79e87f1f8a8444194cdca81d38f5393abf"
+dependencies = [
+ "cpufeatures",
+ "opaque-debug",
+ "universal-hash",
+]
+
 [[package]]
 name = "polyval"
 version = "0.6.2"
@@ -1503,6 +2134,18 @@ dependencies = [
  "universal-hash",
 ]
 
+[[package]]
+name = "postcard"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6764c3b5dd454e283a30e6dfe78e9b31096d9e32036b5d1eaac7a6119ccb9a24"
+dependencies = [
+ "cobs",
+ "embedded-io 0.4.0",
+ "embedded-io 0.6.1",
+ "serde",
+]
+
 [[package]]
 name = "potential_utf"
 version = "0.1.4"
@@ -1513,21 +2156,49 @@ dependencies = [
 ]
 
 [[package]]
-name = "ppv-lite86"
-version = "0.2.21"
+name = "powerfmt"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "439ee305def115ba05938db6eb1644ff94165c5ab5e9420d1c1bcedbba909391"
+
+[[package]]
+name = "ppv-lite86"
+version = "0.2.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85eae3c4ed2f50dcfe72643da4befc30deadb458a9b590d720cde2f2b1e97da9"
+dependencies = [
+ "zerocopy",
+]
+
+[[package]]
+name = "prettyplease"
+version = "0.2.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "479ca8adacdd7ce8f1fb39ce9ecccbfe93a3f1344b3d0d97f20bc0196208f62b"
+dependencies = [
+ "proc-macro2",
+ "syn",
+]
+
+[[package]]
+name = "proc-macro-error-attr2"
+version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "85eae3c4ed2f50dcfe72643da4befc30deadb458a9b590d720cde2f2b1e97da9"
+checksum = "96de42df36bb9bba5542fe9f1a054b8cc87e172759a1868aa05c1f3acc89dfc5"
 dependencies = [
- "zerocopy",
+ "proc-macro2",
+ "quote",
 ]
 
 [[package]]
-name = "prettyplease"
-version = "0.2.37"
+name = "proc-macro-error2"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "479ca8adacdd7ce8f1fb39ce9ecccbfe93a3f1344b3d0d97f20bc0196208f62b"
+checksum = "11ec05c52be0a07b08061f7dd003e7d7092e0472bc731b4af7bb1ef876109802"
 dependencies = [
+ "proc-macro-error-attr2",
  "proc-macro2",
+ "quote",
  "syn",
 ]
 
@@ -1728,6 +2399,56 @@ dependencies = [
  "rand_core 0.9.5",
 ]
 
+[[package]]
+name = "rayon"
+version = "1.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "368f01d005bf8fd9b1206fb6fa653e6c4a81ceb1466406b81792d87c5677a58f"
+dependencies = [
+ "either",
+ "rayon-core",
+]
+
+[[package]]
+name = "rayon-core"
+version = "1.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22e18b0f0062d30d4230b2e85ff77fdfe4326feb054b9783a3460d8435c8ab91"
+dependencies = [
+ "crossbeam-deque",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "reddsa"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78a5191930e84973293aa5f532b513404460cd2216c1cfb76d08748c15b40b02"
+dependencies = [
+ "blake2b_simd",
+ "byteorder",
+ "group",
+ "hex",
+ "jubjub",
+ "pasta_curves",
+ "rand_core 0.6.4",
+ "serde",
+ "thiserror 1.0.69",
+ "zeroize",
+]
+
+[[package]]
+name = "redjubjub"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "89b0ac1bc6bb3696d2c6f52cff8fba57238b81da8c0214ee6cd146eb8fde364e"
+dependencies = [
+ "rand_core 0.6.4",
+ "reddsa",
+ "thiserror 1.0.69",
+ "zeroize",
+]
+
 [[package]]
 name = "regex-syntax"
 version = "0.8.10"
@@ -1769,7 +2490,7 @@ dependencies = [
  "wasm-bindgen",
  "wasm-bindgen-futures",
  "web-sys",
- "webpki-roots",
+ "webpki-roots 1.0.6",
 ]
 
 [[package]]
@@ -1778,7 +2499,7 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8dd2a808d456c4a54e300a23e9f5a67e122c3024119acbfd73e3bf664491cb2"
 dependencies = [
- "hmac",
+ "hmac 0.12.1",
  "subtle",
 ]
 
@@ -1802,7 +2523,16 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bd124222d17ad93a644ed9d011a40f4fb64aa54275c08cc216524a9ea82fb09f"
 dependencies = [
- "digest",
+ "digest 0.10.7",
+]
+
+[[package]]
+name = "ripemd"
+version = "0.2.0-pre.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e48cf93482ea998ad1302c42739bc73ab3adc574890c373ec89710e219357579"
+dependencies = [
+ "digest 0.11.0-pre.9",
 ]
 
 [[package]]
@@ -1860,6 +2590,7 @@ version = "0.23.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "758025cb5fccfd3bc2fd74708fd4682be41d99e5dff73c377c0646c6012c73a4"
 dependencies = [
+ "log",
  "once_cell",
  "ring",
  "rustls-pki-types",
@@ -1868,6 +2599,15 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "rustls-pemfile"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dce314e5fee3f39953d46bb63bb8a46d40c2f8fb7cc5a3b6cab2bde9721d6e50"
+dependencies = [
+ "rustls-pki-types",
+]
+
 [[package]]
 name = "rustls-pki-types"
 version = "1.14.0"
@@ -1910,6 +2650,39 @@ dependencies = [
  "cipher",
 ]
 
+[[package]]
+name = "sapling-crypto"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f9d3c081c83f1dc87403d9d71a06f52301c0aa9ea4c17da2a3435bbf493ffba4"
+dependencies = [
+ "aes",
+ "bellman",
+ "bitvec",
+ "blake2b_simd",
+ "blake2s_simd",
+ "bls12_381",
+ "core2",
+ "document-features",
+ "ff",
+ "fpe",
+ "getset",
+ "group",
+ "hex",
+ "incrementalmerkletree",
+ "jubjub",
+ "lazy_static",
+ "memuse",
+ "rand 0.8.5",
+ "rand_core 0.6.4",
+ "redjubjub",
+ "subtle",
+ "tracing",
+ "zcash_note_encryption",
+ "zcash_spec",
+ "zip32",
+]
+
 [[package]]
 name = "scrypt"
 version = "0.11.0"
@@ -1919,7 +2692,7 @@ dependencies = [
  "password-hash",
  "pbkdf2",
  "salsa20",
- "sha2",
+ "sha2 0.10.9",
 ]
 
 [[package]]
@@ -1936,6 +2709,33 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "secp256k1"
+version = "0.29.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9465315bc9d4566e1724f0fffcbcc446268cb522e60f9a27bcded6b19c108113"
+dependencies = [
+ "secp256k1-sys",
+]
+
+[[package]]
+name = "secp256k1-sys"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4387882333d3aa8cb20530a17c69a3752e97837832f34f6dccc760e715001d9"
+dependencies = [
+ "cc",
+]
+
+[[package]]
+name = "secrecy"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9bd1c54ea06cfd2f6b63219704de0b9b4f72dcc2b8fdef820be6cd799780e91e"
+dependencies = [
+ "zeroize",
+]
+
 [[package]]
 name = "semver"
 version = "1.0.27"
@@ -1997,6 +2797,44 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "serde_with"
+version = "3.18.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd5414fad8e6907dbdd5bc441a50ae8d6e26151a03b1de04d89a5576de61d01f"
+dependencies = [
+ "base64 0.22.1",
+ "chrono",
+ "hex",
+ "serde_core",
+ "serde_json",
+ "serde_with_macros",
+ "time",
+]
+
+[[package]]
+name = "serde_with_macros"
+version = "3.18.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3db8978e608f1fe7357e211969fd9abdcae80bac1ba7a3369bb7eb6b404eb65"
+dependencies = [
+ "darling",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "sha1"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3bf829a2d51ab4a5ddf1352d8470c140cadc8301b2ae1789db023f01cedd6ba"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest 0.10.7",
+]
+
 [[package]]
 name = "sha2"
 version = "0.10.9"
@@ -2005,7 +2843,18 @@ checksum = "a7507d819769d01a365ab707794a4084392c824f54a7a6a7862f8c3d0892b283"
 dependencies = [
  "cfg-if",
  "cpufeatures",
- "digest",
+ "digest 0.10.7",
+]
+
+[[package]]
+name = "sha2"
+version = "0.11.0-pre.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "540c0893cce56cdbcfebcec191ec8e0f470dd1889b6e7a0b503e310a94a168f5"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest 0.11.0-pre.9",
 ]
 
 [[package]]
@@ -2014,7 +2863,7 @@ version = "0.10.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "75872d278a8f37ef87fa0ddbda7802605cb18344497949862c0d4dcb291eba60"
 dependencies = [
- "digest",
+ "digest 0.10.7",
  "keccak",
 ]
 
@@ -2050,10 +2899,21 @@ version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "77549399552de45a898a580c1b41d445bf730df867cc44e6c0233bbc4b8329de"
 dependencies = [
- "digest",
+ "digest 0.10.7",
  "rand_core 0.6.4",
 ]
 
+[[package]]
+name = "sinsemilla"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d268ae0ea06faafe1662e9967cd4f9022014f5eeb798e0c302c876df8b7af9c"
+dependencies = [
+ "group",
+ "pasta_curves",
+ "subtle",
+]
+
 [[package]]
 name = "slab"
 version = "0.4.12"
@@ -2086,6 +2946,12 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "spin"
+version = "0.9.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6980e8d7511241f8acf4aebddbb1ff938df5eebe98691418c4468d0b72a96a67"
+
 [[package]]
 name = "spki"
 version = "0.7.3"
@@ -2102,6 +2968,12 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ce2be8dc25455e1f91df71bfa12ad37d7af1092ae736f3a6cd0e37bc7810596"
 
+[[package]]
+name = "static_assertions"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
+
 [[package]]
 name = "strsim"
 version = "0.11.1"
@@ -2204,6 +3076,25 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "time"
+version = "0.3.47"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "743bd48c283afc0388f9b8827b976905fb217ad9e647fae3a379a9283c4def2c"
+dependencies = [
+ "deranged",
+ "num-conv",
+ "powerfmt",
+ "serde_core",
+ "time-core",
+]
+
+[[package]]
+name = "time-core"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7694e1cfe791f8d31026952abf09c69ca6f6fa4e1a1229e18988f06a04a12dca"
+
 [[package]]
 name = "tinystr"
 version = "0.8.2"
@@ -2310,13 +3201,16 @@ dependencies = [
  "percent-encoding",
  "pin-project",
  "prost",
+ "rustls-pemfile",
  "socket2 0.5.10",
  "tokio",
+ "tokio-rustls",
  "tokio-stream",
  "tower 0.4.13",
  "tower-layer",
  "tower-service",
  "tracing",
+ "webpki-roots 0.26.11",
 ]
 
 [[package]]
@@ -2427,6 +3321,18 @@ version = "1.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "562d481066bde0658276a35467c4af00bdc6ee726305698a55b86e61d7ad82bb"
 
+[[package]]
+name = "uint"
+version = "0.9.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76f64bba2c53b04fcab63c01a7d7427eadc821e3bc48c34dc9ba29c501164b52"
+dependencies = [
+ "byteorder",
+ "crunchy",
+ "hex",
+ "static_assertions",
+]
+
 [[package]]
 name = "unarray"
 version = "0.1.4"
@@ -2451,7 +3357,7 @@ version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fc1de2c688dc15305988b563c3854064043356019f97a4b46276fe734c4f07ea"
 dependencies = [
- "crypto-common",
+ "crypto-common 0.1.7",
  "subtle",
 ]
 
@@ -2502,6 +3408,17 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
 
+[[package]]
+name = "visibility"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d674d135b4a8c1d7e813e2f8d1c9a58308aee4a680323066025e53132218bd91"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "want"
 version = "0.3.1"
@@ -2648,6 +3565,15 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "webpki-roots"
+version = "0.26.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "521bc38abb08001b01866da9f51eb7c5d647a19260e00054a8c7fd5f9e57f7a9"
+dependencies = [
+ "webpki-roots 1.0.6",
+]
+
 [[package]]
 name = "webpki-roots"
 version = "1.0.6"
@@ -3007,6 +3933,178 @@ dependencies = [
  "synstructure",
 ]
 
+[[package]]
+name = "zcash_address"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee4491dddd232de02df42481757054dc19c8bc51cf709cfec58feebfef7c3c9a"
+dependencies = [
+ "bech32 0.11.1",
+ "bs58",
+ "core2",
+ "f4jumble",
+ "zcash_encoding",
+ "zcash_protocol",
+]
+
+[[package]]
+name = "zcash_encoding"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bca38087e6524e5f51a5b0fb3fc18f36d7b84bf67b2056f494ca0c281590953d"
+dependencies = [
+ "core2",
+ "nonempty",
+]
+
+[[package]]
+name = "zcash_keys"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c115531caa1b7ca5ccd82dc26dbe3ba44b7542e928a3f77cd04abbe3cde4a4f2"
+dependencies = [
+ "bech32 0.11.1",
+ "bip32",
+ "blake2b_simd",
+ "bls12_381",
+ "bs58",
+ "core2",
+ "document-features",
+ "group",
+ "memuse",
+ "nonempty",
+ "orchard",
+ "rand_core 0.6.4",
+ "sapling-crypto",
+ "secrecy",
+ "subtle",
+ "tracing",
+ "zcash_address",
+ "zcash_encoding",
+ "zcash_protocol",
+ "zcash_transparent",
+ "zip32",
+]
+
+[[package]]
+name = "zcash_note_encryption"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77efec759c3798b6e4d829fcc762070d9b229b0f13338c40bf993b7b609c2272"
+dependencies = [
+ "chacha20",
+ "chacha20poly1305",
+ "cipher",
+ "rand_core 0.6.4",
+ "subtle",
+]
+
+[[package]]
+name = "zcash_primitives"
+version = "0.26.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fd9ff256fb298a7e94a73c1adad6c7e0b4b194b902e777ee9f5f2e12c4c4776"
+dependencies = [
+ "bip32",
+ "blake2b_simd",
+ "block-buffer 0.11.0-rc.3",
+ "bs58",
+ "core2",
+ "crypto-common 0.2.0-rc.1",
+ "document-features",
+ "equihash",
+ "ff",
+ "fpe",
+ "getset",
+ "group",
+ "hex",
+ "incrementalmerkletree",
+ "jubjub",
+ "memuse",
+ "nonempty",
+ "orchard",
+ "rand 0.8.5",
+ "rand_core 0.6.4",
+ "redjubjub",
+ "ripemd 0.1.3",
+ "sapling-crypto",
+ "sha2 0.10.9",
+ "subtle",
+ "tracing",
+ "zcash_address",
+ "zcash_encoding",
+ "zcash_note_encryption",
+ "zcash_protocol",
+ "zcash_script",
+ "zcash_spec",
+ "zcash_transparent",
+ "zip32",
+]
+
+[[package]]
+name = "zcash_protocol"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "18b1a337bbc9a7d55ae35d31189f03507dbc7934e9a4bee5c1d5c47464860e48"
+dependencies = [
+ "core2",
+ "document-features",
+ "hex",
+ "memuse",
+]
+
+[[package]]
+name = "zcash_script"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c6ef9d04e0434a80b62ad06c5a610557be358ef60a98afa5dbc8ecaf19ad72e7"
+dependencies = [
+ "bip32",
+ "bitflags",
+ "bounded-vec",
+ "hex",
+ "ripemd 0.1.3",
+ "secp256k1",
+ "sha1",
+ "sha2 0.10.9",
+ "thiserror 2.0.18",
+]
+
+[[package]]
+name = "zcash_spec"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ded3f58b93486aa79b85acba1001f5298f27a46489859934954d262533ee2915"
+dependencies = [
+ "blake2b_simd",
+]
+
+[[package]]
+name = "zcash_transparent"
+version = "0.6.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a9b7b4bc11d8bb20833d1b8ab6807f4dca941b381f1129e5bbd72a84e391991"
+dependencies = [
+ "bip32",
+ "blake2b_simd",
+ "bs58",
+ "core2",
+ "document-features",
+ "getset",
+ "hex",
+ "nonempty",
+ "ripemd 0.1.3",
+ "secp256k1",
+ "sha2 0.10.9",
+ "subtle",
+ "zcash_address",
+ "zcash_encoding",
+ "zcash_protocol",
+ "zcash_script",
+ "zcash_spec",
+ "zip32",
+]
+
 [[package]]
 name = "zerocopy"
 version = "0.8.47"
@@ -3101,6 +4199,19 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "zip32"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b64bf5186a8916f7a48f2a98ef599bf9c099e2458b36b819e393db1c0e768c4b"
+dependencies = [
+ "bech32 0.11.1",
+ "blake2b_simd",
+ "memuse",
+ "subtle",
+ "zcash_spec",
+]
+
 [[package]]
 name = "zmij"
 version = "1.0.21"
diff --git a/ows/crates/ows-cli/Cargo.toml b/ows/crates/ows-cli/Cargo.toml
index ec77bab4..055f80eb 100644
--- a/ows/crates/ows-cli/Cargo.toml
+++ b/ows/crates/ows-cli/Cargo.toml
@@ -11,6 +11,10 @@ readme = "README.md"
 name = "ows"
 path = "src/main.rs"
 
+[features]
+default = ["zcash-shielded"]
+zcash-shielded = ["ows-lib/zcash-shielded", "ows-signer/zcash-shielded"]
+
 [dependencies]
 ows-core = { path = "../ows-core", version = "=1.0.0" }
 ows-signer = { path = "../ows-signer", version = "=1.0.0" }
diff --git a/ows/crates/ows-cli/src/commands/derive.rs b/ows/crates/ows-cli/src/commands/derive.rs
index 01ada86a..7bc8b03f 100644
--- a/ows/crates/ows-cli/src/commands/derive.rs
+++ b/ows/crates/ows-cli/src/commands/derive.rs
@@ -4,33 +4,37 @@ use zeroize::Zeroize;
 
 use crate::{parse_chain, CliError};
 
+fn derive_address_for_chain(
+    mnemonic: &Mnemonic,
+    chain_type: ows_core::ChainType,
+    index: u32,
+) -> Result<String, CliError> {
+    let signer = signer_for_chain(chain_type);
+
+    if signer.needs_raw_seed() {
+        let seed = mnemonic.to_seed("");
+        Ok(signer.derive_address_from_seed(seed.expose(), index)?)
+    } else {
+        let path = signer.default_derivation_path(index);
+        let curve = signer.curve();
+        let key = HdDeriver::derive_from_mnemonic_cached(mnemonic, "", &path, curve)?;
+        Ok(signer.derive_address(key.expose())?)
+    }
+}
+
 pub fn run(chain_str: Option<&str>, index: u32) -> Result<(), CliError> {
     let mut mnemonic_str = super::read_mnemonic()?;
     let mnemonic = Mnemonic::from_phrase(&mnemonic_str)?;
     mnemonic_str.zeroize();
 
     if let Some(cs) = chain_str {
-        // Derive for a single chain
         let chain = parse_chain(cs)?;
-        let signer = signer_for_chain(chain.chain_type);
-        let path = signer.default_derivation_path(index);
-        let curve = signer.curve();
-
-        let key = HdDeriver::derive_from_mnemonic_cached(&mnemonic, "", &path, curve)?;
-        let address = signer.derive_address(key.expose())?;
-
+        let address = derive_address_for_chain(&mnemonic, chain.chain_type, index)?;
         println!("{address}");
     } else {
-        // Derive for all chains
         for ct in &ALL_CHAIN_TYPES {
             let chain = default_chain_for_type(*ct);
-            let signer = signer_for_chain(*ct);
-            let path = signer.default_derivation_path(index);
-            let curve = signer.curve();
-
-            let key = HdDeriver::derive_from_mnemonic_cached(&mnemonic, "", &path, curve)?;
-            let address = signer.derive_address(key.expose())?;
-
+            let address = derive_address_for_chain(&mnemonic, *ct, index)?;
             println!("{} → {}", chain.chain_id, address);
         }
     }
diff --git a/ows/crates/ows-cli/src/commands/send_transaction.rs b/ows/crates/ows-cli/src/commands/send_transaction.rs
index 6dc4fe3a..7da58cef 100644
--- a/ows/crates/ows-cli/src/commands/send_transaction.rs
+++ b/ows/crates/ows-cli/src/commands/send_transaction.rs
@@ -38,8 +38,41 @@ pub fn run(
         return Ok(());
     }
 
-    // Owner mode: resolve key directly (existing behavior)
+    // Owner mode
     let chain = parse_chain(chain_str)?;
+
+    // Zcash PCZT: route through sign_and_send which handles seed-based key resolution.
+    // Must be checked before resolve_signing_key so passphrase handling is consistent.
+    #[cfg(feature = "zcash-shielded")]
+    if chain.chain_type == ows_core::ChainType::Zcash {
+        let result = match ows_lib::sign_and_send(
+            wallet_name, chain_str, tx_hex, Some(""), Some(index), rpc_url_override, None,
+        ) {
+            Ok(r) => r,
+            Err(ows_lib::OwsLibError::Crypto(_)) => {
+                let passphrase = super::read_passphrase();
+                ows_lib::sign_and_send(
+                    wallet_name, chain_str, tx_hex,
+                    Some(&passphrase), Some(index), rpc_url_override, None,
+                )?
+            }
+            Err(e) => return Err(e.into()),
+        };
+
+        if json_output {
+            let obj = serde_json::json!({
+                "tx_hash": result.tx_hash,
+                "chain": chain_str,
+            });
+            println!("{}", serde_json::to_string_pretty(&obj)?);
+        } else {
+            println!("{}", result.tx_hash);
+        }
+
+        audit::log_broadcast(wallet_name, chain_str, &result.tx_hash);
+        return Ok(());
+    }
+
     let key = super::resolve_signing_key(wallet_name, chain.chain_type, index)?;
 
     let tx_hex_clean = tx_hex.strip_prefix("0x").unwrap_or(tx_hex);
diff --git a/ows/crates/ows-cli/src/commands/sign_message.rs b/ows/crates/ows-cli/src/commands/sign_message.rs
index 92d180ad..fa8e12d6 100644
--- a/ows/crates/ows-cli/src/commands/sign_message.rs
+++ b/ows/crates/ows-cli/src/commands/sign_message.rs
@@ -35,8 +35,16 @@ pub fn run(
         return print_result(&result.signature, result.recovery_id, json_output);
     }
 
-    // Owner mode: resolve key directly (existing behavior)
+    // Owner mode
     let chain = parse_chain(chain_str)?;
+
+    #[cfg(feature = "zcash-shielded")]
+    if chain.chain_type == ows_core::ChainType::Zcash {
+        return Err(CliError::InvalidArgs(
+            "message signing is not supported for Zcash shielded wallets".into(),
+        ));
+    }
+
     let key = super::resolve_signing_key(wallet_name, chain.chain_type, index)?;
 
     let signer = signer_for_chain(chain.chain_type);
diff --git a/ows/crates/ows-cli/src/commands/sign_transaction.rs b/ows/crates/ows-cli/src/commands/sign_transaction.rs
index 7e491a30..fc99e07b 100644
--- a/ows/crates/ows-cli/src/commands/sign_transaction.rs
+++ b/ows/crates/ows-cli/src/commands/sign_transaction.rs
@@ -34,6 +34,14 @@ pub fn run(
     let tx_bytes = hex::decode(tx_hex_clean)
         .map_err(|e| CliError::InvalidArgs(format!("invalid hex transaction: {e}")))?;
 
+    // Zcash PCZT: the key is the raw seed; route through sign_pczt
+    #[cfg(feature = "zcash-shielded")]
+    if chain.chain_type == ows_core::ChainType::Zcash {
+        let zcash_signer = ows_signer::chains::ZcashSigner::from_chain_id(chain_str);
+        let signed_pczt = zcash_signer.sign_pczt(key.expose(), &tx_bytes, index)?;
+        return print_result(&hex::encode(&signed_pczt), None, json_output);
+    }
+
     let signer = signer_for_chain(chain.chain_type);
     let output = signer.sign_transaction(key.expose(), &tx_bytes)?;
 
diff --git a/ows/crates/ows-core/src/chain.rs b/ows/crates/ows-core/src/chain.rs
index c857d860..87027491 100644
--- a/ows/crates/ows-core/src/chain.rs
+++ b/ows/crates/ows-core/src/chain.rs
@@ -14,10 +14,11 @@ pub enum ChainType {
     Spark,
     Filecoin,
     Sui,
+    Zcash,
 }
 
 /// All supported chain families, used for universal wallet derivation.
-pub const ALL_CHAIN_TYPES: [ChainType; 8] = [
+pub const ALL_CHAIN_TYPES: [ChainType; 9] = [
     ChainType::Evm,
     ChainType::Solana,
     ChainType::Bitcoin,
@@ -26,6 +27,7 @@ pub const ALL_CHAIN_TYPES: [ChainType; 8] = [
     ChainType::Ton,
     ChainType::Filecoin,
     ChainType::Sui,
+    ChainType::Zcash,
 ];
 
 /// A specific chain (e.g. "ethereum", "arbitrum") with its family type and CAIP-2 ID.
@@ -113,6 +115,11 @@ pub const KNOWN_CHAINS: &[Chain] = &[
         chain_type: ChainType::Sui,
         chain_id: "sui:mainnet",
     },
+    Chain {
+        name: "zcash",
+        chain_type: ChainType::Zcash,
+        chain_id: "zcash:mainnet",
+    },
 ];
 
 /// Parse a chain string into a `Chain`. Accepts:
@@ -177,6 +184,7 @@ impl ChainType {
             ChainType::Spark => "spark",
             ChainType::Filecoin => "fil",
             ChainType::Sui => "sui",
+            ChainType::Zcash => "zcash",
         }
     }
 
@@ -192,6 +200,7 @@ impl ChainType {
             ChainType::Spark => 8797555,
             ChainType::Filecoin => 461,
             ChainType::Sui => 784,
+            ChainType::Zcash => 133,
         }
     }
 
@@ -207,6 +216,7 @@ impl ChainType {
             "spark" => Some(ChainType::Spark),
             "fil" => Some(ChainType::Filecoin),
             "sui" => Some(ChainType::Sui),
+            "zcash" => Some(ChainType::Zcash),
             _ => None,
         }
     }
@@ -224,6 +234,7 @@ impl fmt::Display for ChainType {
             ChainType::Spark => "spark",
             ChainType::Filecoin => "filecoin",
             ChainType::Sui => "sui",
+            ChainType::Zcash => "zcash",
         };
         write!(f, "{}", s)
     }
@@ -243,6 +254,7 @@ impl FromStr for ChainType {
             "spark" => Ok(ChainType::Spark),
             "filecoin" => Ok(ChainType::Filecoin),
             "sui" => Ok(ChainType::Sui),
+            "zcash" => Ok(ChainType::Zcash),
             _ => Err(format!("unknown chain type: {}", s)),
         }
     }
@@ -273,6 +285,7 @@ mod tests {
             (ChainType::Spark, "\"spark\""),
             (ChainType::Filecoin, "\"filecoin\""),
             (ChainType::Sui, "\"sui\""),
+            (ChainType::Zcash, "\"zcash\""),
         ] {
             let json = serde_json::to_string(&chain).unwrap();
             assert_eq!(json, expected);
@@ -292,6 +305,7 @@ mod tests {
         assert_eq!(ChainType::Spark.namespace(), "spark");
         assert_eq!(ChainType::Filecoin.namespace(), "fil");
         assert_eq!(ChainType::Sui.namespace(), "sui");
+        assert_eq!(ChainType::Zcash.namespace(), "zcash");
     }
 
     #[test]
@@ -305,6 +319,7 @@ mod tests {
         assert_eq!(ChainType::Spark.default_coin_type(), 8797555);
         assert_eq!(ChainType::Filecoin.default_coin_type(), 461);
         assert_eq!(ChainType::Sui.default_coin_type(), 784);
+        assert_eq!(ChainType::Zcash.default_coin_type(), 133);
     }
 
     #[test]
@@ -321,6 +336,7 @@ mod tests {
         assert_eq!(ChainType::from_namespace("spark"), Some(ChainType::Spark));
         assert_eq!(ChainType::from_namespace("fil"), Some(ChainType::Filecoin));
         assert_eq!(ChainType::from_namespace("sui"), Some(ChainType::Sui));
+        assert_eq!(ChainType::from_namespace("zcash"), Some(ChainType::Zcash));
         assert_eq!(ChainType::from_namespace("unknown"), None);
     }
 
@@ -372,7 +388,7 @@ mod tests {
 
     #[test]
     fn test_all_chain_types() {
-        assert_eq!(ALL_CHAIN_TYPES.len(), 8);
+        assert_eq!(ALL_CHAIN_TYPES.len(), 9);
     }
 
     #[test]
diff --git a/ows/crates/ows-core/src/config.rs b/ows/crates/ows-core/src/config.rs
index 3d45a2d1..c19e7500 100644
--- a/ows/crates/ows-core/src/config.rs
+++ b/ows/crates/ows-core/src/config.rs
@@ -63,6 +63,14 @@ impl Config {
             "sui:mainnet".into(),
             "https://fullnode.mainnet.sui.io:443".into(),
         );
+        rpc.insert(
+            "zcash:mainnet".into(),
+            "https://zec.rocks:443".into(),
+        );
+        rpc.insert(
+            "zcash:testnet".into(),
+            "https://testnet.zec.rocks:443".into(),
+        );
         rpc
     }
 }
@@ -242,7 +250,7 @@ mod tests {
     fn test_load_or_default_nonexistent() {
         let config = Config::load_or_default_from(std::path::Path::new("/nonexistent/config.json"));
         // Should have all default RPCs
-        assert_eq!(config.rpc.len(), 14);
+        assert_eq!(config.rpc.len(), 16);
         assert_eq!(config.rpc_url("eip155:1"), Some("https://eth.llamarpc.com"));
     }
 
diff --git a/ows/crates/ows-lib/Cargo.toml b/ows/crates/ows-lib/Cargo.toml
index 3a46c17a..a8dd95d3 100644
--- a/ows/crates/ows-lib/Cargo.toml
+++ b/ows/crates/ows-lib/Cargo.toml
@@ -10,6 +10,7 @@ readme = "README.md"
 [features]
 default = []
 fast-kdf = ["ows-signer/fast-kdf"]
+zcash-shielded = ["ows-signer/zcash-shielded", "pczt", "zcash_primitives", "tonic/tls", "tonic/tls-webpki-roots"]
 
 [dependencies]
 ows-core = { path = "../ows-core", version = "=1.0.0" }
@@ -28,6 +29,8 @@ rand = "0.8"
 prost = "0.13"
 tonic = { version = "0.12", features = ["transport"] }
 tokio = { version = "1", features = ["rt"] }
+pczt = { version = "0.5", features = ["tx-extractor"], optional = true }
+zcash_primitives = { version = "0.26", optional = true }
 
 [dev-dependencies]
 tempfile = "3"
diff --git a/ows/crates/ows-lib/src/lib.rs b/ows/crates/ows-lib/src/lib.rs
index cfa6e859..13f0bc0d 100644
--- a/ows/crates/ows-lib/src/lib.rs
+++ b/ows/crates/ows-lib/src/lib.rs
@@ -1,6 +1,8 @@
 pub mod error;
 pub mod key_ops;
 pub mod key_store;
+#[cfg(feature = "zcash-shielded")]
+pub mod lwd_grpc;
 pub mod migrate;
 pub mod ops;
 pub mod policy_engine;
diff --git a/ows/crates/ows-lib/src/lwd_grpc.rs b/ows/crates/ows-lib/src/lwd_grpc.rs
new file mode 100644
index 00000000..e6df45e6
--- /dev/null
+++ b/ows/crates/ows-lib/src/lwd_grpc.rs
@@ -0,0 +1,84 @@
+use crate::error::OwsLibError;
+
+/// Hand-written prost message types matching the lightwalletd gRPC proto.
+/// See: https://github.com/zcash/lightwalletd/blob/master/walletrpc/service.proto
+
+#[derive(Clone, PartialEq, prost::Message)]
+pub struct RawTransaction {
+    #[prost(bytes = "vec", tag = "1")]
+    pub data: Vec<u8>,
+    #[prost(uint64, tag = "2")]
+    pub height: u64,
+}
+
+#[derive(Clone, PartialEq, prost::Message)]
+pub struct SendResponse {
+    #[prost(int32, tag = "1")]
+    pub error_code: i32,
+    #[prost(string, tag = "2")]
+    pub error_message: String,
+}
+
+/// Send a raw Zcash transaction to a lightwalletd instance via gRPC.
+///
+/// `endpoint` is the lightwalletd gRPC URL (e.g. `https://zec.rocks:443`).
+/// `tx_bytes` is the fully serialized, finalized Zcash transaction.
+///
+/// Returns the transaction ID (txid) as a hex string on success.
+pub fn send_transaction(endpoint: &str, tx_bytes: &[u8]) -> Result<String, OwsLibError> {
+    let rt = tokio::runtime::Builder::new_current_thread()
+        .enable_all()
+        .build()
+        .map_err(|e| OwsLibError::BroadcastFailed(format!("failed to create runtime: {e}")))?;
+
+    rt.block_on(async {
+        let tls = tonic::transport::ClientTlsConfig::new()
+            .with_webpki_roots();
+        let channel = tonic::transport::Channel::from_shared(endpoint.to_string())
+            .map_err(|e| OwsLibError::BroadcastFailed(format!("invalid endpoint: {e}")))?
+            .tls_config(tls)
+            .map_err(|e| OwsLibError::BroadcastFailed(format!("TLS config failed: {e}")))?
+            .connect()
+            .await
+            .map_err(|e| OwsLibError::BroadcastFailed(format!("gRPC connect failed: {e}")))?;
+
+        let mut client = tonic::client::Grpc::new(channel);
+
+        client
+            .ready()
+            .await
+            .map_err(|e| OwsLibError::BroadcastFailed(format!("gRPC not ready: {e}")))?;
+
+        let request = RawTransaction {
+            data: tx_bytes.to_vec(),
+            height: 0,
+        };
+
+        let path = tonic::codegen::http::uri::PathAndQuery::from_static(
+            "/cash.z.wallet.sdk.rpc.CompactTxStreamer/SendTransaction",
+        );
+        let codec = tonic::codec::ProstCodec::default();
+
+        let response: tonic::Response<SendResponse> = client
+            .unary(tonic::Request::new(request), path, codec)
+            .await
+            .map_err(|e| OwsLibError::BroadcastFailed(format!("gRPC SendTransaction error: {e}")))?;
+
+        let resp = response.into_inner();
+        if resp.error_code != 0 {
+            return Err(OwsLibError::BroadcastFailed(format!(
+                "lightwalletd rejected tx (code {}): {}",
+                resp.error_code, resp.error_message
+            )));
+        }
+
+        // lightwalletd returns the txid in the error_message field on success
+        if resp.error_message.is_empty() {
+            Err(OwsLibError::BroadcastFailed(
+                "broadcast succeeded but lightwalletd did not return a txid".into(),
+            ))
+        } else {
+            Ok(resp.error_message)
+        }
+    })
+}
diff --git a/ows/crates/ows-lib/src/ops.rs b/ows/crates/ows-lib/src/ops.rs
index 6eca56b0..c38ae047 100644
--- a/ows/crates/ows-lib/src/ops.rs
+++ b/ows/crates/ows-lib/src/ops.rs
@@ -42,10 +42,19 @@ fn derive_all_accounts(mnemonic: &Mnemonic, index: u32) -> Result<Vec<WalletAcco
     for ct in &ALL_CHAIN_TYPES {
         let chain = default_chain_for_type(*ct);
         let signer = signer_for_chain(*ct);
-        let path = signer.default_derivation_path(index);
-        let curve = signer.curve();
-        let key = HdDeriver::derive_from_mnemonic(mnemonic, "", &path, curve)?;
-        let address = signer.derive_address(key.expose())?;
+
+        let (address, path) = if signer.needs_raw_seed() {
+            let seed = mnemonic.to_seed("");
+            let addr = signer.derive_address_from_seed(seed.expose(), index)?;
+            (addr, format!("zip32/{}", index))
+        } else {
+            let path = signer.default_derivation_path(index);
+            let curve = signer.curve();
+            let key = HdDeriver::derive_from_mnemonic(mnemonic, "", &path, curve)?;
+            let addr = signer.derive_address(key.expose())?;
+            (addr, path)
+        };
+
         let account_id = format!("{}:{}", chain.chain_id, address);
         accounts.push(WalletAccount {
             account_id,
@@ -151,9 +160,16 @@ pub fn derive_address(
     let chain = parse_chain(chain)?;
     let mnemonic = Mnemonic::from_phrase(mnemonic_phrase)?;
     let signer = signer_for_chain(chain.chain_type);
-    let path = signer.default_derivation_path(index.unwrap_or(0));
-    let curve = signer.curve();
+    let idx = index.unwrap_or(0);
 
+    if signer.needs_raw_seed() {
+        let seed = mnemonic.to_seed("");
+        let address = signer.derive_address_from_seed(seed.expose(), idx)?;
+        return Ok(address);
+    }
+
+    let path = signer.default_derivation_path(idx);
+    let curve = signer.curve();
     let key = HdDeriver::derive_from_mnemonic(&mnemonic, "", &path, curve)?;
     let address = signer.derive_address(key.expose())?;
     Ok(address)
@@ -416,6 +432,22 @@ pub fn sign_transaction(
     // Agent mode: token-based signing with policy enforcement
     if credential.starts_with(crate::key_store::TOKEN_PREFIX) {
         let chain = parse_chain(chain)?;
+
+        #[cfg(feature = "zcash-shielded")]
+        if chain.chain_type == ows_core::ChainType::Zcash {
+            let (key, _) = crate::key_ops::enforce_policy_and_decrypt_key(
+                credential, wallet, &chain, &tx_bytes, index, vault_path,
+            )?;
+            let zcash_signer = ows_signer::chains::ZcashSigner::from_chain_id(chain.chain_id);
+            let signed_pczt = zcash_signer.sign_pczt(
+                key.expose(), &tx_bytes, index.unwrap_or(0),
+            )?;
+            return Ok(SignResult {
+                signature: hex::encode(&signed_pczt),
+                recovery_id: None,
+            });
+        }
+
         return crate::key_ops::sign_with_api_key(
             credential, wallet, &chain, &tx_bytes, index, vault_path,
         );
@@ -424,6 +456,23 @@ pub fn sign_transaction(
     // Owner mode: existing passphrase-based signing (unchanged)
     let chain = parse_chain(chain)?;
     let key = decrypt_signing_key(wallet, chain.chain_type, credential, index, vault_path)?;
+
+    // Zcash PCZT: the seed is returned (64 bytes) and tx_bytes is a serialized PCZT.
+    // Route through ZcashSigner::sign_pczt which returns the signed PCZT bytes.
+    #[cfg(feature = "zcash-shielded")]
+    if chain.chain_type == ows_core::ChainType::Zcash {
+        let zcash_signer = ows_signer::chains::ZcashSigner::from_chain_id(chain.chain_id);
+        let signed_pczt = zcash_signer.sign_pczt(
+            key.expose(),
+            &tx_bytes,
+            index.unwrap_or(0),
+        )?;
+        return Ok(SignResult {
+            signature: hex::encode(&signed_pczt),
+            recovery_id: None,
+        });
+    }
+
     let signer = signer_for_chain(chain.chain_type);
     let output = signer.sign_transaction(key.expose(), &tx_bytes)?;
 
@@ -470,6 +519,14 @@ pub fn sign_message(
 
     // Owner mode
     let chain = parse_chain(chain)?;
+
+    #[cfg(feature = "zcash-shielded")]
+    if chain.chain_type == ows_core::ChainType::Zcash {
+        return Err(OwsLibError::InvalidInput(
+            "message signing is not supported for Zcash shielded wallets".into(),
+        ));
+    }
+
     let key = decrypt_signing_key(wallet, chain.chain_type, credential, index, vault_path)?;
     let signer = signer_for_chain(chain.chain_type);
     let output = signer.sign_message(key.expose(), &msg_bytes)?;
@@ -550,6 +607,12 @@ pub fn sign_and_send(
             index,
             vault_path,
         )?;
+
+        #[cfg(feature = "zcash-shielded")]
+        if chain_info.chain_type == ows_core::ChainType::Zcash {
+            return sign_and_broadcast_zcash(key.expose(), &tx_bytes, index, rpc_url, chain);
+        }
+
         return sign_encode_and_broadcast(key.expose(), chain, &tx_bytes, rpc_url);
     }
 
@@ -557,9 +620,55 @@ pub fn sign_and_send(
     let chain_info = parse_chain(chain)?;
     let key = decrypt_signing_key(wallet, chain_info.chain_type, credential, index, vault_path)?;
 
+    // Zcash PCZT: sign the PCZT and broadcast the finalized transaction.
+    // The key is the raw seed (64 bytes) when zcash-shielded is enabled.
+    #[cfg(feature = "zcash-shielded")]
+    if chain_info.chain_type == ows_core::ChainType::Zcash {
+        return sign_and_broadcast_zcash(key.expose(), &tx_bytes, index, rpc_url, chain);
+    }
+
     sign_encode_and_broadcast(key.expose(), chain, &tx_bytes, rpc_url)
 }
 
+/// Sign a Zcash PCZT, finalize it, and broadcast via lightwalletd.
+///
+/// `seed` is the raw BIP-39 seed (64 bytes).
+/// `pczt_bytes` is the serialized PCZT (already through Creator + Prover stages).
+///
+/// The pipeline: sign PCZT → extract finalized tx bytes → broadcast via gRPC.
+#[cfg(feature = "zcash-shielded")]
+fn sign_and_broadcast_zcash(
+    seed: &[u8],
+    pczt_bytes: &[u8],
+    index: Option<u32>,
+    rpc_url: Option<&str>,
+    chain_str: &str,
+) -> Result<SendResult, OwsLibError> {
+    let zcash_signer = ows_signer::chains::ZcashSigner::from_chain_id(chain_str);
+    let signed_pczt_bytes = zcash_signer.sign_pczt(seed, pczt_bytes, index.unwrap_or(0))?;
+
+    let signed_pczt = pczt::Pczt::parse(&signed_pczt_bytes).map_err(|e| {
+        OwsLibError::InvalidInput(format!("failed to parse signed PCZT: {e:?}"))
+    })?;
+
+    let tx = pczt::roles::tx_extractor::TransactionExtractor::new(signed_pczt)
+        .extract()
+        .map_err(|e| {
+            OwsLibError::InvalidInput(format!("PCZT finalization failed: {e:?}"))
+        })?;
+
+    let mut tx_bytes = Vec::new();
+    tx.write(&mut tx_bytes).map_err(|e| {
+        OwsLibError::InvalidInput(format!("failed to serialize Zcash transaction: {e}"))
+    })?;
+
+    let chain = parse_chain(chain_str)?;
+    let rpc = resolve_rpc_url(chain.chain_id, chain.chain_type, rpc_url)?;
+    let tx_hash = broadcast(chain.chain_type, &rpc, &tx_bytes)?;
+
+    Ok(SendResult { tx_hash })
+}
+
 /// Sign, encode, and broadcast a transaction using an already-resolved private key.
 ///
 /// This is the shared core of the send-transaction flow. Both the library's
@@ -612,17 +721,22 @@ pub fn decrypt_signing_key(
 
     match wallet.key_type {
         KeyType::Mnemonic => {
-            // Use the SecretBytes directly as a &str to avoid un-zeroized String copies.
             let phrase = std::str::from_utf8(secret.expose()).map_err(|_| {
                 OwsLibError::InvalidInput("wallet contains invalid UTF-8 mnemonic".into())
             })?;
             let mnemonic = Mnemonic::from_phrase(phrase)?;
             let signer = signer_for_chain(chain_type);
-            let path = signer.default_derivation_path(index.unwrap_or(0));
-            let curve = signer.curve();
-            Ok(HdDeriver::derive_from_mnemonic_cached(
-                &mnemonic, "", &path, curve,
-            )?)
+
+            if signer.needs_raw_seed() {
+                let seed = mnemonic.to_seed("");
+                Ok(seed)
+            } else {
+                let path = signer.default_derivation_path(index.unwrap_or(0));
+                let curve = signer.curve();
+                Ok(HdDeriver::derive_from_mnemonic_cached(
+                    &mnemonic, "", &path, curve,
+                )?)
+            }
         }
         KeyType::PrivateKey => {
             // JSON key pair — extract the right key for this chain's curve
@@ -688,6 +802,12 @@ fn broadcast(chain: ChainType, rpc_url: &str, signed_bytes: &[u8]) -> Result<Str
             "broadcast not yet supported for Filecoin".into(),
         )),
         ChainType::Sui => broadcast_sui(rpc_url, signed_bytes),
+        #[cfg(feature = "zcash-shielded")]
+        ChainType::Zcash => broadcast_zcash(rpc_url, signed_bytes),
+        #[cfg(not(feature = "zcash-shielded"))]
+        ChainType::Zcash => Err(OwsLibError::InvalidInput(
+            "Zcash broadcast requires the zcash-shielded feature".into(),
+        )),
     }
 }
 
@@ -802,6 +922,11 @@ fn broadcast_sui(rpc_url: &str, signed_bytes: &[u8]) -> Result<String, OwsLibErr
     crate::sui_grpc::execute_transaction(rpc_url, tx_part, sig_part)
 }
 
+#[cfg(feature = "zcash-shielded")]
+fn broadcast_zcash(rpc_url: &str, tx_bytes: &[u8]) -> Result<String, OwsLibError> {
+    crate::lwd_grpc::send_transaction(rpc_url, tx_bytes)
+}
+
 fn curl_post_json(url: &str, body: &str) -> Result<String, OwsLibError> {
     let output = Command::new("curl")
         .args([
@@ -2607,4 +2732,236 @@ mod tests {
             "sign_message owner path must match direct signer"
         );
     }
+
+    // ================================================================
+    // ZCASH INTEGRATION TESTS
+    // ================================================================
+
+    #[test]
+    fn zcash_wallet_create_includes_zcash_account() {
+        let dir = tempfile::tempdir().unwrap();
+        let vault = dir.path();
+        let info = create_wallet("zec-create", None, None, Some(vault)).unwrap();
+
+        let zcash_account = info
+            .accounts
+            .iter()
+            .find(|a| a.chain_id == "zcash:mainnet");
+        assert!(
+            zcash_account.is_some(),
+            "wallet must include a zcash:mainnet account"
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_wallet_create_derives_unified_address() {
+        let dir = tempfile::tempdir().unwrap();
+        let vault = dir.path();
+        let info = create_wallet("zec-ua", None, None, Some(vault)).unwrap();
+
+        let zcash_account = info
+            .accounts
+            .iter()
+            .find(|a| a.chain_id == "zcash:mainnet")
+            .expect("wallet must include a zcash:mainnet account");
+
+        assert!(
+            zcash_account.address.starts_with("u1"),
+            "Zcash address should be a unified address (u1...), got: {}",
+            zcash_account.address
+        );
+        assert!(
+            zcash_account.address.len() > 50,
+            "unified address should be long (multiple receivers), got len: {}",
+            zcash_account.address.len()
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_derive_address_produces_unified_address() {
+        let phrase = generate_mnemonic(12).unwrap();
+        let addr = derive_address(&phrase, "zcash", None).unwrap();
+        assert!(
+            addr.starts_with("u1"),
+            "derived Zcash address should be unified (u1...), got: {}",
+            addr
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_derive_address_deterministic() {
+        let phrase = generate_mnemonic(12).unwrap();
+        let a = derive_address(&phrase, "zcash", None).unwrap();
+        let b = derive_address(&phrase, "zcash", None).unwrap();
+        assert_eq!(a, b, "same mnemonic must produce same Zcash unified address");
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_derive_address_different_accounts() {
+        let phrase = generate_mnemonic(12).unwrap();
+        let a = derive_address(&phrase, "zcash", Some(0)).unwrap();
+        let b = derive_address(&phrase, "zcash", Some(1)).unwrap();
+        assert_ne!(a, b, "different account indices must produce different addresses");
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_import_wallet_address_matches_derivation() {
+        let dir = tempfile::tempdir().unwrap();
+        let vault = dir.path();
+        let phrase = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about";
+
+        let info =
+            import_wallet_mnemonic("zec-import", phrase, None, None, Some(vault)).unwrap();
+        let zcash_account = info
+            .accounts
+            .iter()
+            .find(|a| a.chain_id == "zcash:mainnet")
+            .expect("imported wallet must include Zcash account");
+
+        let derived = derive_address(phrase, "zcash", None).unwrap();
+        assert_eq!(
+            zcash_account.address, derived,
+            "wallet import and direct derivation must produce the same Zcash address"
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_wallet_export_reimport_address_stable() {
+        let v1 = tempfile::tempdir().unwrap();
+        let v2 = tempfile::tempdir().unwrap();
+
+        let w1 = create_wallet("zec-export", None, None, Some(v1.path())).unwrap();
+        let phrase = export_wallet("zec-export", None, Some(v1.path())).unwrap();
+
+        let w2 =
+            import_wallet_mnemonic("zec-reimport", &phrase, None, None, Some(v2.path())).unwrap();
+
+        let addr1 = w1
+            .accounts
+            .iter()
+            .find(|a| a.chain_id == "zcash:mainnet")
+            .unwrap()
+            .address
+            .clone();
+        let addr2 = w2
+            .accounts
+            .iter()
+            .find(|a| a.chain_id == "zcash:mainnet")
+            .unwrap()
+            .address
+            .clone();
+
+        assert_eq!(
+            addr1, addr2,
+            "Zcash address must be stable across export → reimport"
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_decrypt_signing_key_returns_seed() {
+        let dir = tempfile::tempdir().unwrap();
+        let vault = dir.path();
+        create_wallet("zec-key", None, None, Some(vault)).unwrap();
+
+        let key = decrypt_signing_key("zec-key", ChainType::Zcash, "", None, Some(vault)).unwrap();
+        assert_eq!(
+            key.expose().len(),
+            64,
+            "Zcash signing key should be the raw 64-byte BIP-39 seed"
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_sign_transaction_accepts_pczt_bytes() {
+        use pczt::roles::creator::Creator;
+
+        let dir = tempfile::tempdir().unwrap();
+        let vault = dir.path();
+        create_wallet("zec-sign", None, None, Some(vault)).unwrap();
+
+        // Build a minimal empty PCZT via the Creator role.
+        // No inputs = no signatures needed, but this verifies the full
+        // PCZT routing through the library (hex decode → seed decrypt →
+        // ZcashSigner::sign_pczt → return signed bytes).
+        let pczt = Creator::new(
+            0xc2d6_d0b4, // NU5 consensus branch ID
+            0,            // expiry height
+            133,          // coin type (Zcash)
+            [0u8; 32],   // sapling anchor
+            [0u8; 32],   // orchard anchor
+        )
+        .build();
+        let pczt_hex = hex::encode(pczt.serialize());
+
+        let result = sign_transaction("zec-sign", "zcash", &pczt_hex, None, None, Some(vault));
+        assert!(
+            result.is_ok(),
+            "signing an empty PCZT should succeed (no inputs to sign): {:?}",
+            result.err()
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_sign_transaction_rejects_garbage() {
+        let dir = tempfile::tempdir().unwrap();
+        let vault = dir.path();
+        create_wallet("zec-garbage", None, None, Some(vault)).unwrap();
+
+        let garbage_hex = "deadbeefcafebabe";
+        let result =
+            sign_transaction("zec-garbage", "zcash", garbage_hex, None, None, Some(vault));
+        assert!(
+            result.is_err(),
+            "signing garbage bytes should fail with a PCZT parse error"
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_24_word_mnemonic_derives_valid_address() {
+        let phrase = generate_mnemonic(24).unwrap();
+        let addr = derive_address(&phrase, "zcash", None).unwrap();
+        assert!(
+            addr.starts_with("u1"),
+            "24-word mnemonic should produce unified address, got: {}",
+            addr
+        );
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    #[test]
+    fn zcash_wallet_create_other_chains_unaffected() {
+        let dir = tempfile::tempdir().unwrap();
+        let vault = dir.path();
+        let info = create_wallet("zec-others", None, None, Some(vault)).unwrap();
+
+        let evm = info.accounts.iter().find(|a| a.chain_id.starts_with("eip155:"));
+        let sol = info.accounts.iter().find(|a| a.chain_id.starts_with("solana:"));
+        let btc = info.accounts.iter().find(|a| a.chain_id.starts_with("bip122:"));
+        let zec = info.accounts.iter().find(|a| a.chain_id == "zcash:mainnet");
+
+        assert!(evm.is_some(), "EVM account must exist");
+        assert!(sol.is_some(), "Solana account must exist");
+        assert!(btc.is_some(), "Bitcoin account must exist");
+        assert!(zec.is_some(), "Zcash account must exist");
+
+        assert!(evm.unwrap().address.starts_with("0x"), "EVM format preserved");
+        assert!(zec.unwrap().address.starts_with("u1"), "Zcash format correct");
+
+        let evm_sig = sign_message("zec-others", "evm", "test", None, None, None, Some(vault));
+        assert!(
+            evm_sig.is_ok(),
+            "EVM signing must still work after Zcash integration: {:?}",
+            evm_sig.err()
+        );
+    }
 }
diff --git a/ows/crates/ows-signer/Cargo.toml b/ows/crates/ows-signer/Cargo.toml
index 95a96c64..2051e00d 100644
--- a/ows/crates/ows-signer/Cargo.toml
+++ b/ows/crates/ows-signer/Cargo.toml
@@ -10,6 +10,7 @@ readme = "README.md"
 [features]
 default = []
 fast-kdf = []
+zcash-shielded = ["zcash_keys", "zcash_protocol", "zip32", "pczt", "sapling-crypto", "orchard", "zcash_transparent"]
 
 [dependencies]
 ows-core = { path = "../ows-core", version = "=1.0.0" }
@@ -38,4 +39,13 @@ digest = "0.10"
 libc = "0.2"
 signal-hook = "0.4"
 
+# Zcash shielded support (unified addresses, PCZT signing) — heavy deps, feature-gated
+zcash_keys = { version = "0.12", features = ["orchard", "sapling", "transparent-inputs"], optional = true }
+zcash_protocol = { version = "0.7", optional = true }
+zip32 = { version = "0.2", optional = true }
+pczt = { version = "0.5", features = ["signer"], optional = true }
+sapling-crypto = { version = "0.5", optional = true }
+orchard = { version = "0.11", optional = true }
+zcash_transparent = { version = "0.6", optional = true }
+
 [dev-dependencies]
diff --git a/ows/crates/ows-signer/src/chains/mod.rs b/ows/crates/ows-signer/src/chains/mod.rs
index b73d8a24..95162216 100644
--- a/ows/crates/ows-signer/src/chains/mod.rs
+++ b/ows/crates/ows-signer/src/chains/mod.rs
@@ -7,6 +7,7 @@ pub mod spark;
 pub mod sui;
 pub mod ton;
 pub mod tron;
+pub mod zcash;
 
 pub use self::bitcoin::BitcoinSigner;
 pub use self::cosmos::CosmosSigner;
@@ -17,6 +18,7 @@ pub use self::spark::SparkSigner;
 pub use self::sui::SuiSigner;
 pub use self::ton::TonSigner;
 pub use self::tron::TronSigner;
+pub use self::zcash::ZcashSigner;
 
 use crate::traits::ChainSigner;
 use ows_core::ChainType;
@@ -33,5 +35,6 @@ pub fn signer_for_chain(chain: ChainType) -> Box<dyn ChainSigner> {
         ChainType::Spark => Box::new(SparkSigner),
         ChainType::Filecoin => Box::new(FilecoinSigner),
         ChainType::Sui => Box::new(SuiSigner),
+        ChainType::Zcash => Box::new(ZcashSigner::mainnet()),
     }
 }
diff --git a/ows/crates/ows-signer/src/chains/zcash.rs b/ows/crates/ows-signer/src/chains/zcash.rs
new file mode 100644
index 00000000..aa844d5a
--- /dev/null
+++ b/ows/crates/ows-signer/src/chains/zcash.rs
@@ -0,0 +1,648 @@
+use crate::curve::Curve;
+use crate::traits::{ChainSigner, SignOutput, SignerError};
+use k256::ecdsa::SigningKey;
+use ows_core::ChainType;
+use ripemd::Ripemd160;
+use sha2::{Digest, Sha256};
+
+#[cfg(feature = "zcash-shielded")]
+use zcash_keys::keys::{ReceiverRequirement, UnifiedSpendingKey};
+#[cfg(feature = "zcash-shielded")]
+use zcash_protocol::consensus::Network;
+
+/// Zcash transparent chain signer.
+///
+/// Handles t-address derivation and transparent transaction signing.
+/// Zcash transparent uses the same secp256k1 curve as Bitcoin with
+/// a different address encoding (Base58Check with Zcash-specific
+/// two-byte version prefix, per § 5.6.1 of the protocol spec).
+///
+/// # Transaction signing
+///
+/// Zcash sighash computation uses BLAKE2b-256 with a consensus-branch-specific
+/// personalization string (ZIP-244). Because this requires knowledge of the
+/// consensus branch ID, `sign_transaction` expects a pre-computed 32-byte
+/// sighash — not raw transaction bytes. The caller (e.g. a PCZT builder or
+/// lightwalletd client) is responsible for computing the sighash per ZIP-244.
+///
+/// # Message signing
+///
+/// Follows the same format as zcashd's `signmessage` RPC: a double-SHA256
+/// of the magic-prefixed message, using "Zcash Signed Message:\n" as the
+/// magic string (cf. `strMessageMagic` in zcash/src/main.cpp).
+///
+/// # Shielded transactions
+///
+/// Shielded (Sapling/Orchard) transactions require zero-knowledge proof
+/// generation and use the PCZT format — see the companion RFC.
+pub struct ZcashSigner {
+    /// Two-byte Base58Check version prefix.
+    /// Mainnet P2PKH: [0x1C, 0xB8] → t1...
+    /// Testnet P2PKH: [0x1D, 0x25] → tm...
+    /// (cf. chainparams.cpp base58Prefixes[PUBKEY_ADDRESS])
+    addr_version: [u8; 2],
+}
+
+impl ZcashSigner {
+    pub fn new(addr_version: [u8; 2]) -> Self {
+        ZcashSigner { addr_version }
+    }
+
+    pub fn mainnet() -> Self {
+        Self::new([0x1C, 0xB8])
+    }
+
+    pub fn testnet() -> Self {
+        Self::new([0x1D, 0x25])
+    }
+
+    /// Select mainnet or testnet based on CAIP-2 chain identifier.
+    pub fn from_chain_id(chain_id: &str) -> Self {
+        if chain_id.contains("testnet") {
+            Self::testnet()
+        } else {
+            Self::mainnet()
+        }
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    fn network(&self) -> Network {
+        if self.addr_version == [0x1C, 0xB8] {
+            Network::MainNetwork
+        } else {
+            Network::TestNetwork
+        }
+    }
+
+    /// Derive a unified address (t + sapling + orchard receivers) from a
+    /// raw BIP-39 seed using ZIP-32 derivation.
+    #[cfg(feature = "zcash-shielded")]
+    pub fn derive_unified_address(
+        &self,
+        seed: &[u8],
+        account_index: u32,
+    ) -> Result<String, SignerError> {
+        if seed.len() < 32 {
+            return Err(SignerError::AddressDerivationFailed(format!(
+                "seed must be at least 32 bytes, got {}",
+                seed.len()
+            )));
+        }
+
+        let network = self.network();
+        let account = zip32::AccountId::try_from(account_index).map_err(|e| {
+            SignerError::AddressDerivationFailed(format!("invalid account index: {e}"))
+        })?;
+
+        let usk = UnifiedSpendingKey::from_seed(&network, seed, account).map_err(|e| {
+            SignerError::AddressDerivationFailed(format!("ZIP-32 key derivation failed: {e:?}"))
+        })?;
+
+        let ufvk = usk.to_unified_full_viewing_key();
+
+        let request = zcash_keys::keys::UnifiedAddressRequest::unsafe_custom(
+            ReceiverRequirement::Require,
+            ReceiverRequirement::Require,
+            ReceiverRequirement::Omit,
+        );
+
+        let (ua, _diversifier_index) = ufvk.default_address(request).map_err(|e| {
+            SignerError::AddressDerivationFailed(format!(
+                "unified address derivation failed: {e}"
+            ))
+        })?;
+
+        Ok(ua.encode(&network))
+    }
+
+    /// Sign a PCZT (Partially Created Zcash Transaction).
+    ///
+    /// OWS acts as the Signer role: it receives a PCZT that has already been
+    /// through Creator + Prover, applies spend authorization signatures for
+    /// all transparent, Sapling, and Orchard inputs, and returns the signed PCZT.
+    ///
+    /// The `seed` must be the raw BIP-39 seed (64 bytes). The USK is derived
+    /// via ZIP-32 to extract the per-pool signing keys.
+    #[cfg(feature = "zcash-shielded")]
+    pub fn sign_pczt(
+        &self,
+        seed: &[u8],
+        pczt_bytes: &[u8],
+        account_index: u32,
+    ) -> Result<Vec<u8>, SignerError> {
+        use zcash_transparent::keys::NonHardenedChildIndex;
+
+        if seed.len() < 32 {
+            return Err(SignerError::InvalidPrivateKey(format!(
+                "seed must be at least 32 bytes, got {}",
+                seed.len()
+            )));
+        }
+
+        let network = self.network();
+        let account = zip32::AccountId::try_from(account_index).map_err(|e| {
+            SignerError::SigningFailed(format!("invalid account index: {e}"))
+        })?;
+
+        let usk = UnifiedSpendingKey::from_seed(&network, seed, account).map_err(|e| {
+            SignerError::SigningFailed(format!("ZIP-32 key derivation failed: {e:?}"))
+        })?;
+
+        let pczt = pczt::Pczt::parse(pczt_bytes).map_err(|e| {
+            SignerError::InvalidTransaction(format!("failed to parse PCZT: {e:?}"))
+        })?;
+
+        let n_transparent = pczt.transparent().inputs().len();
+        let n_sapling = pczt.sapling().spends().len();
+        let n_orchard = pczt.orchard().actions().len();
+
+        let mut signer = pczt::roles::signer::Signer::new(pczt).map_err(|e| {
+            SignerError::SigningFailed(format!("failed to initialize PCZT signer: {e:?}"))
+        })?;
+
+        if n_transparent > 0 {
+            // Derive external scope at index 0 (the primary receiving address).
+            // Inputs at other indices are skipped via TransparentSign error below,
+            // consistent with how Sapling/Orchard skip non-matching keys.
+            let scope = zcash_transparent::keys::TransparentKeyScope::from(
+                zip32::Scope::External,
+            );
+            let transparent_sk = usk
+                .transparent()
+                .derive_secret_key(scope, NonHardenedChildIndex::ZERO)
+                .map_err(|e| {
+                    SignerError::SigningFailed(format!(
+                        "failed to derive transparent secret key: {e:?}"
+                    ))
+                })?;
+            for i in 0..n_transparent {
+                match signer.sign_transparent(i, &transparent_sk) {
+                    Ok(()) => {}
+                    Err(pczt::roles::signer::Error::TransparentSign(_)) => {
+                        // Not our input (different key) — skip it
+                    }
+                    Err(e) => {
+                        return Err(SignerError::SigningFailed(format!(
+                            "transparent input {i} signing failed: {e:?}"
+                        )));
+                    }
+                }
+            }
+        }
+
+        if n_sapling > 0 {
+            let sapling_ask = &usk.sapling().expsk.ask;
+            for i in 0..n_sapling {
+                match signer.sign_sapling(i, sapling_ask) {
+                    Ok(()) => {}
+                    Err(pczt::roles::signer::Error::SaplingSign(_)) => {
+                        // Not our spend (different key or dummy) — skip it
+                    }
+                    Err(e) => {
+                        return Err(SignerError::SigningFailed(format!(
+                            "sapling spend {i} signing failed: {e:?}"
+                        )));
+                    }
+                }
+            }
+        }
+
+        if n_orchard > 0 {
+            let orchard_ask = orchard::keys::SpendAuthorizingKey::from(usk.orchard());
+            for i in 0..n_orchard {
+                match signer.sign_orchard(i, &orchard_ask) {
+                    Ok(()) => {}
+                    Err(pczt::roles::signer::Error::OrchardSign(
+                        orchard::pczt::SignerError::WrongSpendAuthorizingKey,
+                    )) => {
+                        // Not our action (dummy/padding spend) — skip it
+                    }
+                    Err(e) => {
+                        return Err(SignerError::SigningFailed(format!(
+                            "orchard action {i} signing failed: {e:?}"
+                        )));
+                    }
+                }
+            }
+        }
+
+        let signed_pczt = signer.finish();
+        Ok(signed_pczt.serialize())
+    }
+
+    fn signing_key(private_key: &[u8]) -> Result<SigningKey, SignerError> {
+        SigningKey::from_slice(private_key)
+            .map_err(|e| SignerError::InvalidPrivateKey(e.to_string()))
+    }
+
+    fn hash160(data: &[u8]) -> Vec<u8> {
+        let sha256 = Sha256::digest(data);
+        let ripemd = Ripemd160::digest(sha256);
+        ripemd.to_vec()
+    }
+}
+
+/// Encode an integer as a Bitcoin/Zcash CompactSize (varint).
+fn encode_compact_size(buf: &mut Vec<u8>, n: usize) {
+    if n < 253 {
+        buf.push(n as u8);
+    } else if n <= 0xFFFF {
+        buf.push(0xFD);
+        buf.extend_from_slice(&(n as u16).to_le_bytes());
+    } else if n <= 0xFFFF_FFFF {
+        buf.push(0xFE);
+        buf.extend_from_slice(&(n as u32).to_le_bytes());
+    } else {
+        buf.push(0xFF);
+        buf.extend_from_slice(&(n as u64).to_le_bytes());
+    }
+}
+
+impl ChainSigner for ZcashSigner {
+    fn chain_type(&self) -> ChainType {
+        ChainType::Zcash
+    }
+
+    fn curve(&self) -> Curve {
+        Curve::Secp256k1
+    }
+
+    fn coin_type(&self) -> u32 {
+        133
+    }
+
+    fn derive_address(&self, private_key: &[u8]) -> Result<String, SignerError> {
+        let signing_key = Self::signing_key(private_key)?;
+        let verifying_key = signing_key.verifying_key();
+
+        let pubkey_compressed = verifying_key.to_encoded_point(true);
+        let pubkey_bytes = pubkey_compressed.as_bytes();
+
+        let hash = Self::hash160(pubkey_bytes);
+
+        // Base58Check: version_bytes (2) ++ hash160 (20) ++ checksum (4)
+        let mut payload = Vec::with_capacity(2 + 20 + 4);
+        payload.extend_from_slice(&self.addr_version);
+        payload.extend_from_slice(&hash);
+
+        let checksum = Sha256::digest(Sha256::digest(&payload));
+        payload.extend_from_slice(&checksum[..4]);
+
+        Ok(bs58::encode(&payload).into_string())
+    }
+
+    fn sign(&self, private_key: &[u8], message: &[u8]) -> Result<SignOutput, SignerError> {
+        if message.len() != 32 {
+            return Err(SignerError::InvalidMessage(format!(
+                "expected 32-byte hash, got {} bytes",
+                message.len()
+            )));
+        }
+
+        let signing_key = Self::signing_key(private_key)?;
+        let (signature, recovery_id) = signing_key
+            .sign_prehash_recoverable(message)
+            .map_err(|e| SignerError::SigningFailed(e.to_string()))?;
+
+        let mut sig_bytes = signature.to_bytes().to_vec();
+        sig_bytes.push(recovery_id.to_byte());
+
+        Ok(SignOutput {
+            signature: sig_bytes,
+            recovery_id: Some(recovery_id.to_byte()),
+            public_key: None,
+        })
+    }
+
+    fn sign_transaction(
+        &self,
+        private_key: &[u8],
+        tx_bytes: &[u8],
+    ) -> Result<SignOutput, SignerError> {
+        // Zcash transaction sighash is computed per ZIP-244 using BLAKE2b-256
+        // with a consensus-branch-specific personalization ("ZcashTxHash_" ||
+        // CONSENSUS_BRANCH_ID). Because the signer does not know the branch ID,
+        // callers must pre-compute the 32-byte sighash and pass it directly.
+        //
+        // This matches how PCZT (Partially Created Zcash Transaction) works:
+        // the Creator/Prover computes the sighash, and the Signer just signs it.
+        if tx_bytes.len() != 32 {
+            return Err(SignerError::InvalidTransaction(
+                "Zcash requires a pre-computed 32-byte sighash per ZIP-244. \
+                 Raw transaction bytes are not supported — use a transaction \
+                 builder to compute the sighash (BLAKE2b-256 with branch-specific \
+                 personalization) before calling sign_transaction."
+                    .to_string(),
+            ));
+        }
+        self.sign(private_key, tx_bytes)
+    }
+
+    fn sign_message(&self, private_key: &[u8], message: &[u8]) -> Result<SignOutput, SignerError> {
+        // Zcash message signing follows the same format as zcashd signmessage RPC:
+        // double-SHA256 of (magic_prefix || CompactSize(message_len) || message).
+        //
+        // Magic: "\x16Zcash Signed Message:\n"
+        //   \x16 = 22 = byte length of "Zcash Signed Message:\n"
+        //   (cf. strMessageMagic in zcash/src/main.cpp)
+        let prefix = b"\x16Zcash Signed Message:\n";
+        let mut data = Vec::new();
+        data.extend_from_slice(prefix);
+        encode_compact_size(&mut data, message.len());
+        data.extend_from_slice(message);
+
+        let hash = Sha256::digest(Sha256::digest(&data));
+        self.sign(private_key, &hash)
+    }
+
+    fn default_derivation_path(&self, index: u32) -> String {
+        format!("m/44'/133'/0'/0/{}", index)
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    fn needs_raw_seed(&self) -> bool {
+        true
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    fn derive_address_from_seed(
+        &self,
+        seed: &[u8],
+        account_index: u32,
+    ) -> Result<String, SignerError> {
+        self.derive_unified_address(seed, account_index)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn test_privkey() -> Vec<u8> {
+        // Private key = 1 (generator point G)
+        let mut privkey = vec![0u8; 31];
+        privkey.push(1u8);
+        privkey
+    }
+
+    #[test]
+    fn test_mainnet_t_address_known_value() {
+        // Private key = 1 → secp256k1 generator point G
+        // Compressed pubkey: 0279BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798
+        // hash160: 751e76e8199196d454941c45d1b3a323f1433bd6
+        // Base58Check with version [0x1C, 0xB8] → t1UYsZVJkLPeMjxEtACvSxfWuNmddpWfxzs
+        // (independently verified via Python and cross-referenced with Bitcoin's
+        // 1BgGZ9tcN4rm9KBzDn7KprQz87SZ26SAMH which shares the same hash160)
+        let signer = ZcashSigner::mainnet();
+        let address = signer.derive_address(&test_privkey()).unwrap();
+        assert_eq!(
+            address, "t1UYsZVJkLPeMjxEtACvSxfWuNmddpWfxzs",
+            "address must match known value for generator point"
+        );
+    }
+
+    #[test]
+    fn test_testnet_tm_address() {
+        let signer = ZcashSigner::testnet();
+        let address = signer.derive_address(&test_privkey()).unwrap();
+        assert!(
+            address.starts_with("tm"),
+            "testnet address should start with tm, got: {}",
+            address
+        );
+        assert_eq!(address.len(), 35, "t-addr must be 35 characters");
+    }
+
+    #[test]
+    fn test_chain_properties() {
+        let signer = ZcashSigner::mainnet();
+        assert_eq!(signer.chain_type(), ChainType::Zcash);
+        assert_eq!(signer.curve(), Curve::Secp256k1);
+        assert_eq!(signer.coin_type(), 133);
+    }
+
+    #[test]
+    fn test_derivation_path() {
+        let signer = ZcashSigner::mainnet();
+        assert_eq!(signer.default_derivation_path(0), "m/44'/133'/0'/0/0");
+        assert_eq!(signer.default_derivation_path(3), "m/44'/133'/0'/0/3");
+    }
+
+    #[test]
+    fn test_sign_transaction_accepts_32_byte_sighash() {
+        use k256::ecdsa::signature::hazmat::PrehashVerifier;
+
+        let signer = ZcashSigner::mainnet();
+        let privkey = test_privkey();
+
+        // Simulate a pre-computed 32-byte sighash (as ZIP-244 would produce)
+        let sighash = Sha256::digest(b"simulated ZIP-244 sighash preimage");
+
+        let result = signer.sign_transaction(&privkey, &sighash).unwrap();
+
+        let signing_key = SigningKey::from_slice(&privkey).unwrap();
+        let verifying_key = signing_key.verifying_key();
+        let r: [u8; 32] = result.signature[..32].try_into().unwrap();
+        let s: [u8; 32] = result.signature[32..64].try_into().unwrap();
+        let sig = k256::ecdsa::Signature::from_scalars(r, s).unwrap();
+
+        verifying_key
+            .verify_prehash(&sighash, &sig)
+            .expect("signature must verify against the provided sighash");
+    }
+
+    #[test]
+    fn test_sign_transaction_rejects_raw_bytes() {
+        let signer = ZcashSigner::mainnet();
+        let privkey = test_privkey();
+
+        let result = signer.sign_transaction(&privkey, b"not a 32-byte sighash");
+        assert!(result.is_err(), "must reject non-32-byte input");
+
+        let err = result.unwrap_err().to_string();
+        assert!(
+            err.contains("ZIP-244"),
+            "error should reference ZIP-244, got: {}",
+            err
+        );
+    }
+
+    #[test]
+    fn test_sign_message_short() {
+        use k256::ecdsa::signature::hazmat::PrehashVerifier;
+
+        let signer = ZcashSigner::mainnet();
+        let privkey = test_privkey();
+        let message = b"Hello Zcash!";
+
+        let result = signer.sign_message(&privkey, message).unwrap();
+
+        // Verify against correctly constructed hash:
+        // \x16 (22) + "Zcash Signed Message:\n" + CompactSize(12) + message
+        let mut expected_data = Vec::new();
+        expected_data.extend_from_slice(b"\x16Zcash Signed Message:\n");
+        expected_data.push(message.len() as u8);
+        expected_data.extend_from_slice(message);
+        let expected_hash = Sha256::digest(Sha256::digest(&expected_data));
+
+        let signing_key = SigningKey::from_slice(&privkey).unwrap();
+        let verifying_key = signing_key.verifying_key();
+        let r: [u8; 32] = result.signature[..32].try_into().unwrap();
+        let s: [u8; 32] = result.signature[32..64].try_into().unwrap();
+        let sig = k256::ecdsa::Signature::from_scalars(r, s).unwrap();
+
+        verifying_key
+            .verify_prehash(&expected_hash, &sig)
+            .expect("signature must verify for short messages");
+    }
+
+    #[test]
+    fn test_sign_message_long_varint() {
+        use k256::ecdsa::signature::hazmat::PrehashVerifier;
+
+        let signer = ZcashSigner::mainnet();
+        let privkey = test_privkey();
+        let message = vec![0x42u8; 300];
+
+        let result = signer.sign_message(&privkey, &message).unwrap();
+
+        // CompactSize for 300: 0xFD followed by 300 as 2-byte LE
+        let mut expected_data = Vec::new();
+        expected_data.extend_from_slice(b"\x16Zcash Signed Message:\n");
+        expected_data.push(0xFD);
+        expected_data.extend_from_slice(&300u16.to_le_bytes());
+        expected_data.extend_from_slice(&message);
+        let expected_hash = Sha256::digest(Sha256::digest(&expected_data));
+
+        let signing_key = SigningKey::from_slice(&privkey).unwrap();
+        let verifying_key = signing_key.verifying_key();
+        let r: [u8; 32] = result.signature[..32].try_into().unwrap();
+        let s: [u8; 32] = result.signature[32..64].try_into().unwrap();
+        let sig = k256::ecdsa::Signature::from_scalars(r, s).unwrap();
+
+        verifying_key
+            .verify_prehash(&expected_hash, &sig)
+            .expect("signature must verify for long messages with varint");
+    }
+
+    #[test]
+    fn test_sign_message_varint_boundary() {
+        use k256::ecdsa::signature::hazmat::PrehashVerifier;
+
+        let signer = ZcashSigner::mainnet();
+        let privkey = test_privkey();
+        let message = vec![0xAA; 253];
+
+        let result = signer.sign_message(&privkey, &message).unwrap();
+
+        // 253 is the boundary where single-byte CompactSize becomes invalid
+        let mut expected_data = Vec::new();
+        expected_data.extend_from_slice(b"\x16Zcash Signed Message:\n");
+        expected_data.push(0xFD);
+        expected_data.extend_from_slice(&253u16.to_le_bytes());
+        expected_data.extend_from_slice(&message);
+        let expected_hash = Sha256::digest(Sha256::digest(&expected_data));
+
+        let signing_key = SigningKey::from_slice(&privkey).unwrap();
+        let verifying_key = signing_key.verifying_key();
+        let r: [u8; 32] = result.signature[..32].try_into().unwrap();
+        let s: [u8; 32] = result.signature[32..64].try_into().unwrap();
+        let sig = k256::ecdsa::Signature::from_scalars(r, s).unwrap();
+
+        verifying_key
+            .verify_prehash(&expected_hash, &sig)
+            .expect("signature must verify at varint boundary");
+    }
+
+    #[test]
+    fn test_deterministic() {
+        let signer = ZcashSigner::mainnet();
+        let addr1 = signer.derive_address(&test_privkey()).unwrap();
+        let addr2 = signer.derive_address(&test_privkey()).unwrap();
+        assert_eq!(addr1, addr2);
+    }
+
+    #[cfg(feature = "zcash-shielded")]
+    mod shielded_tests {
+        use super::*;
+        use crate::mnemonic::Mnemonic;
+
+        const ABANDON_PHRASE: &str = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about";
+
+        fn test_seed() -> Vec<u8> {
+            let mnemonic = Mnemonic::from_phrase(ABANDON_PHRASE).unwrap();
+            let seed = mnemonic.to_seed("");
+            seed.expose().to_vec()
+        }
+
+        #[test]
+        fn test_unified_address_mainnet() {
+            let signer = ZcashSigner::mainnet();
+            let seed = test_seed();
+            let address = signer.derive_unified_address(&seed, 0).unwrap();
+            assert!(
+                address.starts_with("u1"),
+                "mainnet unified address should start with u1, got: {}",
+                address
+            );
+            assert!(
+                address.len() > 50,
+                "unified address should be long (has multiple receivers), got len: {}",
+                address.len()
+            );
+        }
+
+        #[test]
+        fn test_unified_address_testnet() {
+            let signer = ZcashSigner::testnet();
+            let seed = test_seed();
+            let address = signer.derive_unified_address(&seed, 0).unwrap();
+            assert!(
+                address.starts_with("utest1"),
+                "testnet unified address should start with utest1, got: {}",
+                address
+            );
+        }
+
+        #[test]
+        fn test_unified_address_deterministic() {
+            let signer = ZcashSigner::mainnet();
+            let seed = test_seed();
+            let addr1 = signer.derive_unified_address(&seed, 0).unwrap();
+            let addr2 = signer.derive_unified_address(&seed, 0).unwrap();
+            assert_eq!(addr1, addr2);
+        }
+
+        #[test]
+        fn test_unified_address_different_accounts() {
+            let signer = ZcashSigner::mainnet();
+            let seed = test_seed();
+            let addr0 = signer.derive_unified_address(&seed, 0).unwrap();
+            let addr1 = signer.derive_unified_address(&seed, 1).unwrap();
+            assert_ne!(addr0, addr1, "different accounts must produce different addresses");
+        }
+
+        #[test]
+        fn test_needs_raw_seed() {
+            let signer = ZcashSigner::mainnet();
+            assert!(signer.needs_raw_seed());
+        }
+
+        #[test]
+        fn test_derive_address_from_seed_matches() {
+            let signer = ZcashSigner::mainnet();
+            let seed = test_seed();
+            let addr_direct = signer.derive_unified_address(&seed, 0).unwrap();
+            let addr_trait = signer.derive_address_from_seed(&seed, 0).unwrap();
+            assert_eq!(addr_direct, addr_trait);
+        }
+
+        #[test]
+        fn test_reject_short_seed() {
+            let signer = ZcashSigner::mainnet();
+            let short_seed = vec![0u8; 16];
+            let result = signer.derive_unified_address(&short_seed, 0);
+            assert!(result.is_err(), "should reject seed shorter than 32 bytes");
+        }
+    }
+}
diff --git a/ows/crates/ows-signer/src/traits.rs b/ows/crates/ows-signer/src/traits.rs
index 9ffe5eb3..3bdc7552 100644
--- a/ows/crates/ows-signer/src/traits.rs
+++ b/ows/crates/ows-signer/src/traits.rs
@@ -79,6 +79,32 @@ pub trait ChainSigner: Send + Sync {
 
     /// Returns the default BIP-44 derivation path template for this chain.
     fn default_derivation_path(&self, index: u32) -> String;
+
+    /// Whether this chain requires the raw BIP-39 seed for address derivation
+    /// instead of a BIP-32/SLIP-10 derived key.
+    ///
+    /// Chains using non-standard HD derivation (e.g. Zcash's ZIP-32) override
+    /// this to return `true`, causing the wallet layer to pass the raw 64-byte
+    /// seed to [`derive_address_from_seed`] instead of a 32-byte derived key
+    /// to [`derive_address`].
+    fn needs_raw_seed(&self) -> bool {
+        false
+    }
+
+    /// Derive an on-chain address directly from a raw BIP-39 seed (64 bytes).
+    ///
+    /// Only called when [`needs_raw_seed`] returns `true`. Chains that use
+    /// non-BIP-44 derivation (e.g. ZIP-32 for Zcash unified addresses)
+    /// override this method.
+    fn derive_address_from_seed(
+        &self,
+        _seed: &[u8],
+        _account_index: u32,
+    ) -> Result<String, SignerError> {
+        Err(SignerError::AddressDerivationFailed(
+            "raw seed derivation not supported for this chain".into(),
+        ))
+    }
 }
 
 /// Errors that can occur during signing operations.