From 08293aabff7e66b1adaa79e299cf3e0deb3d1405 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 14:53:05 +0200
Subject: [PATCH 01/24] feat(bitcoin): decode Zcash addresses and accept the
 transparent kinds

---
 packages/sdk-provider-bitcoin/package.json    |  3 +-
 .../src/utils/zcashAddress.ts                 | 77 +++++++++++++++++++
 .../src/utils/zcashAddress.unit.spec.ts       | 72 +++++++++++++++++
 pnpm-lock.yaml                                |  3 +
 4 files changed, 154 insertions(+), 1 deletion(-)
 create mode 100644 packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
 create mode 100644 packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts

diff --git a/packages/sdk-provider-bitcoin/package.json b/packages/sdk-provider-bitcoin/package.json
index 59ee451dc..068ebb8a9 100644
--- a/packages/sdk-provider-bitcoin/package.json
+++ b/packages/sdk-provider-bitcoin/package.json
@@ -48,7 +48,8 @@
     "@bitcoinerlab/secp256k1": "^2.0.0",
     "@lifi/sdk": "workspace:*",
     "bech32": "^2.0.0",
-    "bitcoinjs-lib": "^7.0.2"
+    "bitcoinjs-lib": "^7.0.2",
+    "bs58check": "^4.0.0"
   },
   "devDependencies": {
     "@lifi/data-types": "^7.1.6",
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
new file mode 100644
index 000000000..981429392
--- /dev/null
+++ b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
@@ -0,0 +1,77 @@
+import { type BechLib, bech32, bech32m } from 'bech32'
+import bs58check from 'bs58check'
+
+/** The mainnet Zcash address kinds, named by the receiver they encode. */
+export type ZcashAddressKind = 'p2pkh' | 'p2sh' | 'tex' | 'sapling' | 'unified'
+
+/**
+ * The kinds a LI.FI route may send to. The API handles transparent receivers
+ * only; add a kind here once the backend confirms it.
+ */
+export const acceptedZcashAddressKinds: ReadonlySet<ZcashAddressKind> =
+  new Set<ZcashAddressKind>(['p2pkh', 'p2sh'])
+
+// Unified addresses outgrow Bech32's default 90-character limit: the longest
+// official test vector (zcash-test-vectors, unified_address.json) has 509.
+const bech32LengthLimit = 1024
+
+// A transparent address decodes to a 2-byte version prefix and a 20-byte hash.
+const transparentPayloadLength = 22
+
+const parseTransparentAddress = (
+  address: string
+): ZcashAddressKind | undefined => {
+  const payload = bs58check.decodeUnsafe(address)
+  if (payload?.length !== transparentPayloadLength || payload[0] !== 0x1c) {
+    return undefined
+  }
+  if (payload[1] === 0xb8) {
+    return 'p2pkh'
+  }
+  if (payload[1] === 0xbd) {
+    return 'p2sh'
+  }
+  return undefined
+}
+
+interface Bech32Kind {
+  kind: ZcashAddressKind
+  prefix: string
+  encoding: BechLib
+  /** Unified addresses are F4Jumbled, so only their checksum is checked. */
+  payloadLength?: number
+}
+
+const bech32Kinds: Bech32Kind[] = [
+  { kind: 'tex', prefix: 'tex', encoding: bech32m, payloadLength: 20 },
+  { kind: 'sapling', prefix: 'zs', encoding: bech32, payloadLength: 43 },
+  { kind: 'unified', prefix: 'u', encoding: bech32m },
+]
+
+const parseBech32Address = (address: string): ZcashAddressKind | undefined =>
+  bech32Kinds.find(({ prefix, encoding, payloadLength }) => {
+    const decoded = encoding.decodeUnsafe(address, bech32LengthLimit)
+    if (decoded?.prefix !== prefix) {
+      return false
+    }
+    const payload = encoding.fromWordsUnsafe(decoded.words)
+    return (
+      payload !== undefined &&
+      (payloadLength === undefined || payload.length === payloadLength)
+    )
+  })?.kind
+
+/**
+ * Decodes a mainnet Zcash address and verifies its checksum. A testnet address,
+ * or any other version or prefix, returns `undefined`.
+ */
+export const parseZcashAddress = (
+  address: string
+): ZcashAddressKind | undefined =>
+  parseTransparentAddress(address) ?? parseBech32Address(address)
+
+/** Whether `address` is a Zcash address a LI.FI route may send to. */
+export const isZcashAddress = (address: string): boolean => {
+  const kind = parseZcashAddress(address)
+  return kind !== undefined && acceptedZcashAddressKinds.has(kind)
+}
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts
new file mode 100644
index 000000000..8c162087c
--- /dev/null
+++ b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts
@@ -0,0 +1,72 @@
+import { describe, expect, it } from 'vitest'
+import {
+  acceptedZcashAddressKinds,
+  isZcashAddress,
+  parseZcashAddress,
+} from './zcashAddress.js'
+
+// Sources: ZIP 320 (t1 and its TEX form), ZIP 214 (t3), zcash-test-vectors
+// unified_address.json (u1, and the Sapling raw address of row 0 encoded as zs1).
+const t1 = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
+const t3 = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
+const tex = 'tex1s2rt77ggv6q989lr49rkgzmh5slsksa9khdgte'
+const sapling =
+  'zs1mrhc9y7jdh5r9ece8u5khgvj9kg0zgkxzdduyv0whkg7lkcrkx5xqem3e48avjq9wn2rukydkwn'
+const unified =
+  'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf'
+// The longest entry in unified_address.json: past Bech32's default 90-character limit.
+const unifiedLongest =
+  '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'
+// The t1 above with its last character changed: the checksum no longer matches.
+const t1WithBadChecksum = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yD'
+// Testnet forms of the same hash: version 0x1D25 and HRP `textest`.
+const testnetTransparent = 'tmMcWbZU8t39htCR1fQRfRSHtkW4p3Ax5Se'
+const testnetTex = 'textest1s2rt77ggv6q989lr49rkgzmh5slsksa90ej7wz'
+const bitcoinSegwit = 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
+const bitcoinLegacy = '1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2'
+
+describe('parseZcashAddress', () => {
+  it.each([
+    ['p2pkh', t1],
+    ['p2sh', t3],
+    ['tex', tex],
+    ['sapling', sapling],
+    ['unified', unified],
+    ['unified', unifiedLongest],
+  ])('decodes a %s address', (kind, address) => {
+    expect(parseZcashAddress(address)).toBe(kind)
+  })
+
+  it.each([
+    ['a corrupted checksum', t1WithBadChecksum],
+    ['a testnet transparent address', testnetTransparent],
+    ['a testnet TEX address', testnetTex],
+    ['a Bitcoin segwit address', bitcoinSegwit],
+    ['a Bitcoin legacy address', bitcoinLegacy],
+    ['an EVM address', '0xB095274743941e953c746F9C228DA9c18Bb6ec29'],
+    ['an empty string', ''],
+    ['free text', 'not-an-address'],
+  ])('rejects %s', (_, address) => {
+    expect(parseZcashAddress(address)).toBeUndefined()
+  })
+})
+
+describe('isZcashAddress', () => {
+  it('accepts only the transparent kinds a route may send to', () => {
+    expect([...acceptedZcashAddressKinds].sort()).toEqual(['p2pkh', 'p2sh'])
+    expect(isZcashAddress(t1)).toBe(true)
+    expect(isZcashAddress(t3)).toBe(true)
+  })
+
+  it('refuses kinds the backend does not handle yet', () => {
+    expect(isZcashAddress(tex)).toBe(false)
+    expect(isZcashAddress(sapling)).toBe(false)
+    expect(isZcashAddress(unified)).toBe(false)
+  })
+
+  it('refuses a corrupted checksum and addresses of other chains', () => {
+    expect(isZcashAddress(t1WithBadChecksum)).toBe(false)
+    expect(isZcashAddress(bitcoinSegwit)).toBe(false)
+    expect(isZcashAddress(bitcoinLegacy)).toBe(false)
+  })
+})
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 0de91866d..f57d0fe89 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -258,6 +258,9 @@ importers:
       bitcoinjs-lib:
         specifier: ^7.0.2
         version: 7.0.2(typescript@7.0.2)
+      bs58check:
+        specifier: ^4.0.0
+        version: 4.0.0
     devDependencies:
       '@lifi/data-types':
         specifier: ^7.1.6

From f2fc211fcd0bdad4c380474a06387ec08837a83b Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 14:55:44 +0200
Subject: [PATCH 02/24] feat(sdk): validate an address against a destination
 chain

---
 .../src/BitcoinProvider.ts                    | 20 +++++++-
 .../src/BitcoinProvider.unit.spec.ts          | 46 ++++++++++++++++++-
 .../src/EthereumProvider.ts                   |  7 ++-
 .../src/EthereumProvider.unit.spec.ts         | 22 ++++++++-
 .../src/SolanaProvider.unit.spec.ts           |  9 +++-
 .../src/StellarProvider.unit.spec.ts          |  9 +++-
 .../src/SuiProvider.unit.spec.ts              |  9 +++-
 .../src/TronProvider.unit.spec.ts             |  8 ++++
 packages/sdk/src/types/core.ts                | 10 +++-
 9 files changed, 131 insertions(+), 9 deletions(-)

diff --git a/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts b/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts
index 64787460b..5630c40b6 100644
--- a/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts
+++ b/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts
@@ -1,9 +1,25 @@
 import { isUTXOAddress } from '@bigmi/core'
-import { ChainType, type StepExecutorOptions } from '@lifi/sdk'
+import { ChainId, ChainType, type StepExecutorOptions } from '@lifi/sdk'
 import { getBitcoinBalance } from './actions/getBitcoinBalance.js'
 import { resolveBitcoinAddress } from './actions/resolveBitcoinAddress.js'
 import { BitcoinStepExecutor } from './core/BitcoinStepExecutor.js'
 import type { BitcoinProviderOptions, BitcoinSDKProvider } from './types.js'
+import { isZcashAddress } from './utils/zcashAddress.js'
+
+// Each UTXO chain has its own address format. A chain this provider does not
+// know is refused, so a Bitcoin address never passes as its receiver. The chain
+// ID must not reach bigmi, which reads a second argument as a network.
+const isAddress = (address: string, chainId?: ChainId): boolean => {
+  switch (chainId) {
+    case undefined:
+    case ChainId.BTC:
+      return isUTXOAddress(address)
+    case ChainId.ZEC:
+      return isZcashAddress(address)
+    default:
+      return false
+  }
+}
 
 export function BitcoinProvider(
   options?: BitcoinProviderOptions
@@ -13,7 +29,7 @@ export function BitcoinProvider(
     get type() {
       return ChainType.UTXO
     },
-    isAddress: isUTXOAddress,
+    isAddress,
     resolveAddress: resolveBitcoinAddress,
     getBalance: getBitcoinBalance,
     async getStepExecutor(
diff --git a/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts b/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts
index 92f764b0d..6cf00326b 100644
--- a/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts
+++ b/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts
@@ -1,4 +1,4 @@
-import { ChainType } from '@lifi/sdk'
+import { ChainId, ChainType } from '@lifi/sdk'
 import { describe, expect, it, vi } from 'vitest'
 import { BitcoinProvider } from './BitcoinProvider.js'
 
@@ -52,4 +52,48 @@ describe('BitcoinProvider', () => {
     expect(executor).toBeDefined()
     expect(mockGetWalletClient).toHaveBeenCalledOnce()
   })
+
+  describe('isAddress', () => {
+    const provider = BitcoinProvider()
+    const bitcoinSegwit = 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
+    const bitcoinLegacy = '1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2'
+    const zcashP2pkh = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
+    const zcashP2sh = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
+    const zcashUnified =
+      'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf'
+
+    it('keeps today’s answer without a chain ID and for Bitcoin', () => {
+      for (const address of [
+        bitcoinSegwit,
+        bitcoinLegacy,
+        zcashP2pkh,
+        'not-an-address',
+      ]) {
+        expect(provider.isAddress(address, ChainId.BTC)).toBe(
+          provider.isAddress(address)
+        )
+      }
+      expect(provider.isAddress(bitcoinSegwit)).toBe(true)
+      expect(provider.isAddress(zcashP2pkh)).toBe(false)
+    })
+
+    it('accepts only transparent Zcash addresses for ZEC', () => {
+      expect(provider.isAddress(zcashP2pkh, ChainId.ZEC)).toBe(true)
+      expect(provider.isAddress(zcashP2sh, ChainId.ZEC)).toBe(true)
+      expect(provider.isAddress(zcashUnified, ChainId.ZEC)).toBe(false)
+    })
+
+    it('refuses a Bitcoin address for ZEC and a Zcash address for BTC', () => {
+      expect(provider.isAddress(bitcoinSegwit, ChainId.ZEC)).toBe(false)
+      expect(provider.isAddress(bitcoinLegacy, ChainId.ZEC)).toBe(false)
+      expect(provider.isAddress(zcashP2pkh, ChainId.BTC)).toBe(false)
+    })
+
+    it('refuses every address for a UTXO chain it does not know', () => {
+      for (const chainId of [ChainId.LTC, ChainId.BCH, ChainId.DGE]) {
+        expect(provider.isAddress(bitcoinSegwit, chainId)).toBe(false)
+        expect(provider.isAddress(zcashP2pkh, chainId)).toBe(false)
+      }
+    })
+  })
 })
diff --git a/packages/sdk-provider-ethereum/src/EthereumProvider.ts b/packages/sdk-provider-ethereum/src/EthereumProvider.ts
index 28cca177d..e441435a0 100644
--- a/packages/sdk-provider-ethereum/src/EthereumProvider.ts
+++ b/packages/sdk-provider-ethereum/src/EthereumProvider.ts
@@ -10,6 +10,11 @@ function isEthereumTokenAddress(address: string): boolean {
   return isAddress(address, { strict: false })
 }
 
+/** viem reads a second argument as options, so a chain ID must not reach it. */
+function isEthereumAddress(address: string): boolean {
+  return isAddress(address)
+}
+
 export function EthereumProvider(
   options?: EthereumProviderOptions
 ): EthereumSDKProvider {
@@ -21,7 +26,7 @@ export function EthereumProvider(
     get options() {
       return _options
     },
-    isAddress,
+    isAddress: isEthereumAddress,
     isTokenAddress: isEthereumTokenAddress,
     resolveAddress: resolveEthereumAddress,
     getBalance: getEthereumBalance,
diff --git a/packages/sdk-provider-ethereum/src/EthereumProvider.unit.spec.ts b/packages/sdk-provider-ethereum/src/EthereumProvider.unit.spec.ts
index 0066d4864..a4eb31df1 100644
--- a/packages/sdk-provider-ethereum/src/EthereumProvider.unit.spec.ts
+++ b/packages/sdk-provider-ethereum/src/EthereumProvider.unit.spec.ts
@@ -1,4 +1,4 @@
-import { ChainType } from '@lifi/sdk'
+import { ChainId, ChainType } from '@lifi/sdk'
 import { describe, expect, it, vi } from 'vitest'
 import { EthereumProvider } from './EthereumProvider.js'
 
@@ -86,4 +86,24 @@ describe('EthereumProvider', () => {
     expect(executor).toBeDefined()
     expect(mockGetWalletClient).toHaveBeenCalledOnce()
   })
+
+  describe('isAddress with a chain ID', () => {
+    const provider = EthereumProvider()
+    const usdt = '0xdAC17F958D2ee523a2206206994597C13D831ec7'
+
+    it('answers as without one, for every EVM chain', () => {
+      for (const address of [
+        usdt,
+        usdt.toLowerCase(),
+        `0x${usdt.slice(2).toUpperCase()}`,
+        'laptop',
+      ]) {
+        for (const chainId of [ChainId.ETH, ChainId.ARB]) {
+          expect(provider.isAddress(address, chainId)).toBe(
+            provider.isAddress(address)
+          )
+        }
+      }
+    })
+  })
 })
diff --git a/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts b/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts
index 555d37bb4..b38ef3d1e 100644
--- a/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts
+++ b/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts
@@ -1,4 +1,4 @@
-import { ChainType, ProviderError } from '@lifi/sdk'
+import { ChainId, ChainType, ProviderError } from '@lifi/sdk'
 import { describe, expect, it, vi } from 'vitest'
 import { SolanaProvider } from './SolanaProvider.js'
 
@@ -66,4 +66,11 @@ describe('SolanaProvider', () => {
     expect(executor).toBeDefined()
     expect(mockGetWalletAdapter).toHaveBeenCalledOnce()
   })
+
+  it('answers isAddress as without a chain ID', () => {
+    const provider = SolanaProvider()
+    const usdcMint = 'EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v'
+    expect(provider.isAddress(usdcMint, ChainId.SOL)).toBe(true)
+    expect(provider.isAddress('laptop', ChainId.SOL)).toBe(false)
+  })
 })
diff --git a/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts b/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts
index 06bf8cf7d..fb5aac426 100644
--- a/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts
+++ b/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts
@@ -1,4 +1,4 @@
-import { ChainType } from '@lifi/sdk'
+import { ChainId, ChainType } from '@lifi/sdk'
 import { Account, Keypair, MuxedAccount, StrKey } from '@stellar/stellar-sdk'
 import { describe, expect, it } from 'vitest'
 import { StellarProvider } from './StellarProvider.js'
@@ -87,4 +87,11 @@ describe('StellarProvider', () => {
       expect(provider.isTokenAddress?.('')).toBe(false)
     })
   })
+
+  it('answers isAddress as without a chain ID', () => {
+    const provider = StellarProvider()
+    const g = Keypair.random().publicKey()
+    expect(provider.isAddress(g, ChainId.XLM)).toBe(true)
+    expect(provider.isAddress('laptop', ChainId.XLM)).toBe(false)
+  })
 })
diff --git a/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts b/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts
index 6285a16b8..ba43b71a6 100644
--- a/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts
+++ b/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts
@@ -1,4 +1,4 @@
-import { ChainType, ProviderError } from '@lifi/sdk'
+import { ChainId, ChainType, ProviderError } from '@lifi/sdk'
 import { describe, expect, it, vi } from 'vitest'
 import { SuiProvider } from './SuiProvider.js'
 import { SuiTokenLongAddress, SuiTokenShortAddress } from './types.js'
@@ -99,4 +99,11 @@ describe('SuiProvider', () => {
     expect(mockGetClient).toHaveBeenCalledOnce()
     expect(mockGetSigner).toHaveBeenCalledOnce()
   })
+
+  it('answers isAddress as without a chain ID', () => {
+    const provider = SuiProvider()
+    const wallet = `0x${'ab'.repeat(32)}`
+    expect(provider.isAddress(wallet, ChainId.SUI)).toBe(true)
+    expect(provider.isAddress('laptop', ChainId.SUI)).toBe(false)
+  })
 })
diff --git a/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts b/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts
index b55fb7f50..30634415b 100644
--- a/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts
+++ b/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts
@@ -1,3 +1,4 @@
+import { ChainId } from '@lifi/sdk'
 import { describe, expect, it } from 'vitest'
 import { TronProvider } from './TronProvider.js'
 
@@ -19,4 +20,11 @@ describe('TronProvider', () => {
       expect(provider.isTokenAddress?.('')).toBe(false)
     })
   })
+
+  it('answers isAddress as without a chain ID', () => {
+    const provider = TronProvider()
+    const usdtContract = 'TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t'
+    expect(provider.isAddress(usdtContract, ChainId.TRN)).toBe(true)
+    expect(provider.isAddress('laptop', ChainId.TRN)).toBe(false)
+  })
 })
diff --git a/packages/sdk/src/types/core.ts b/packages/sdk/src/types/core.ts
index 64f4ea666..f28b1b55d 100644
--- a/packages/sdk/src/types/core.ts
+++ b/packages/sdk/src/types/core.ts
@@ -91,7 +91,15 @@ export type RPCUrls = Partial<Record<ChainId, string[]>>
 
 export interface SDKProvider {
   readonly type: ChainType
-  isAddress(address: string): boolean
+  /**
+   * Validates a wallet address. Without `chainId`, the provider accepts any
+   * address format of its ecosystem, as before. `chainId`, when given, is a
+   * chain of this provider's ecosystem: a provider whose chains share one
+   * address format may ignore it; a provider whose chains differ accepts only
+   * that chain's format and refuses a chain it does not know. Never forward
+   * `chainId` to a library function whose second parameter means something else.
+   */
+  isAddress(address: string, chainId?: ChainId): boolean
   /**
    * Validates a token identifier, which several ecosystems shape unlike a
    * wallet address. A provider that omits the method has no token address

From 071bde440f4014fb14170e296b4f866ddbcd1f08 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 14:56:18 +0200
Subject: [PATCH 03/24] fix(bitcoin): leave balances of other UTXO chains
 unknown

---
 .../src/actions/getBitcoinBalance.ts          |  5 ++
 .../actions/getBitcoinBalance.unit.spec.ts    | 51 +++++++++++++++++++
 2 files changed, 56 insertions(+)
 create mode 100644 packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts

diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
index 1b07c60ad..8e54ed355 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
@@ -20,6 +20,11 @@ export const getBitcoinBalance = async (
       console.warn('Requested tokens have to be on the same chain.')
     }
   }
+  // The client reads Bitcoin only. Another UTXO chain, such as ZEC, shares this
+  // provider but not its balances, so its amount stays unknown, not zero.
+  if (chainId !== ChainId.BTC) {
+    return tokens.map((token) => ({ ...token }))
+  }
   const bigmiClient = await getBitcoinPublicClient(client, ChainId.BTC)
   const [balance, blockCount] = await Promise.allSettled([
     bigmiClient.getBalance({ address: walletAddress }),
diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
new file mode 100644
index 000000000..22978cf08
--- /dev/null
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
@@ -0,0 +1,51 @@
+import { ChainId, createClient, type Token } from '@lifi/sdk'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { getBitcoinBalance } from './getBitcoinBalance.js'
+
+const mocks = vi.hoisted(() => ({ getBitcoinPublicClient: vi.fn() }))
+
+vi.mock('../client/publicClient.js', () => ({
+  getBitcoinPublicClient: mocks.getBitcoinPublicClient,
+}))
+
+const client = createClient({ integrator: 'lifi-sdk' })
+const walletAddress = 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
+
+const nativeToken = (chainId: ChainId, symbol: string): Token =>
+  ({
+    chainId,
+    address: symbol.toLowerCase(),
+    symbol,
+    name: symbol,
+    decimals: 8,
+    priceUSD: '0',
+  }) as Token
+
+describe('getBitcoinBalance', () => {
+  beforeEach(() => {
+    mocks.getBitcoinPublicClient.mockReset()
+    mocks.getBitcoinPublicClient.mockResolvedValue({
+      getBalance: vi.fn().mockResolvedValue(1234n),
+      getBlockCount: vi.fn().mockResolvedValue(900_000),
+    })
+  })
+
+  it('reads the Bitcoin balance for BTC', async () => {
+    const [balance] = await getBitcoinBalance(client, walletAddress, [
+      nativeToken(ChainId.BTC, 'BTC'),
+    ])
+
+    expect(balance.amount).toBe(1234n)
+    expect(balance.blockNumber).toBe(900_000n)
+  })
+
+  it('leaves the amount unknown for ZEC and asks no Bitcoin node', async () => {
+    const [balance] = await getBitcoinBalance(client, walletAddress, [
+      nativeToken(ChainId.ZEC, 'ZEC'),
+    ])
+
+    expect(balance.amount).toBeUndefined()
+    expect(balance.symbol).toBe('ZEC')
+    expect(mocks.getBitcoinPublicClient).not.toHaveBeenCalled()
+  })
+})

From a75a5b3f30716b53f6dca4b6b1bb83ba887c5243 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 14:56:55 +0200
Subject: [PATCH 04/24] chore: add changesets for the Zcash address check

---
 .changeset/chain-aware-is-address.md      | 5 +++++
 .changeset/ethereum-is-address-wrapper.md | 5 +++++
 .changeset/zcash-destination-address.md   | 5 +++++
 3 files changed, 15 insertions(+)
 create mode 100644 .changeset/chain-aware-is-address.md
 create mode 100644 .changeset/ethereum-is-address-wrapper.md
 create mode 100644 .changeset/zcash-destination-address.md

diff --git a/.changeset/chain-aware-is-address.md b/.changeset/chain-aware-is-address.md
new file mode 100644
index 000000000..5eedb8ce0
--- /dev/null
+++ b/.changeset/chain-aware-is-address.md
@@ -0,0 +1,5 @@
+---
+'@lifi/sdk': minor
+---
+
+`SDKProvider.isAddress` accepts an optional `chainId`. Without it, a provider answers as before. With it, a provider whose chains use different address formats accepts only that chain's format and refuses a chain it does not know. A provider must never forward the chain ID to a library function whose second parameter means something else.
diff --git a/.changeset/ethereum-is-address-wrapper.md b/.changeset/ethereum-is-address-wrapper.md
new file mode 100644
index 000000000..b41cd3378
--- /dev/null
+++ b/.changeset/ethereum-is-address-wrapper.md
@@ -0,0 +1,5 @@
+---
+'@lifi/sdk-provider-ethereum': patch
+---
+
+`EthereumProvider.isAddress` no longer passes a second argument to viem's `isAddress`, whose second parameter is `options`. Results are unchanged.
diff --git a/.changeset/zcash-destination-address.md b/.changeset/zcash-destination-address.md
new file mode 100644
index 000000000..bfc65346b
--- /dev/null
+++ b/.changeset/zcash-destination-address.md
@@ -0,0 +1,5 @@
+---
+'@lifi/sdk-provider-bitcoin': minor
+---
+
+`BitcoinProvider.isAddress(address, ChainId.ZEC)` validates a Zcash receiver with its checksum. Transparent `t1` and `t3` addresses are accepted; TEX (`tex1`), Sapling (`zs1`) and unified (`u1`) addresses are recognised and refused until the API supports them. Any UTXO chain other than BTC and ZEC is refused, so a Bitcoin address no longer passes as the receiver of a chain whose format the provider does not know. `getBitcoinBalance` now leaves the amount of a non-BTC token unknown instead of reporting the Bitcoin balance for it.

From 03b37731e5506c8e38749e1e8ccd72dc0c21fb45 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 14:57:43 +0200
Subject: [PATCH 05/24] test(sdk): pin isAddress with a chain ID to the answer
 without one

---
 packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts | 5 +++++
 .../sdk-provider-stellar/src/StellarProvider.unit.spec.ts    | 5 +++++
 packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts       | 5 +++++
 packages/sdk-provider-tron/src/TronProvider.unit.spec.ts     | 5 +++++
 4 files changed, 20 insertions(+)

diff --git a/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts b/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts
index b38ef3d1e..96e98dddd 100644
--- a/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts
+++ b/packages/sdk-provider-solana/src/SolanaProvider.unit.spec.ts
@@ -71,6 +71,11 @@ describe('SolanaProvider', () => {
     const provider = SolanaProvider()
     const usdcMint = 'EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v'
     expect(provider.isAddress(usdcMint, ChainId.SOL)).toBe(true)
+    for (const address of [usdcMint, 'laptop']) {
+      expect(provider.isAddress(address, ChainId.SOL)).toBe(
+        provider.isAddress(address)
+      )
+    }
     expect(provider.isAddress('laptop', ChainId.SOL)).toBe(false)
   })
 })
diff --git a/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts b/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts
index fb5aac426..6c4a8976b 100644
--- a/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts
+++ b/packages/sdk-provider-stellar/src/StellarProvider.unit.spec.ts
@@ -92,6 +92,11 @@ describe('StellarProvider', () => {
     const provider = StellarProvider()
     const g = Keypair.random().publicKey()
     expect(provider.isAddress(g, ChainId.XLM)).toBe(true)
+    for (const address of [g, 'laptop']) {
+      expect(provider.isAddress(address, ChainId.XLM)).toBe(
+        provider.isAddress(address)
+      )
+    }
     expect(provider.isAddress('laptop', ChainId.XLM)).toBe(false)
   })
 })
diff --git a/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts b/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts
index ba43b71a6..1f5b2fbf7 100644
--- a/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts
+++ b/packages/sdk-provider-sui/src/SuiProvider.unit.spec.ts
@@ -104,6 +104,11 @@ describe('SuiProvider', () => {
     const provider = SuiProvider()
     const wallet = `0x${'ab'.repeat(32)}`
     expect(provider.isAddress(wallet, ChainId.SUI)).toBe(true)
+    for (const address of [wallet, 'laptop']) {
+      expect(provider.isAddress(address, ChainId.SUI)).toBe(
+        provider.isAddress(address)
+      )
+    }
     expect(provider.isAddress('laptop', ChainId.SUI)).toBe(false)
   })
 })
diff --git a/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts b/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts
index 30634415b..18eb18132 100644
--- a/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts
+++ b/packages/sdk-provider-tron/src/TronProvider.unit.spec.ts
@@ -25,6 +25,11 @@ describe('TronProvider', () => {
     const provider = TronProvider()
     const usdtContract = 'TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t'
     expect(provider.isAddress(usdtContract, ChainId.TRN)).toBe(true)
+    for (const address of [usdtContract, 'laptop']) {
+      expect(provider.isAddress(address, ChainId.TRN)).toBe(
+        provider.isAddress(address)
+      )
+    }
     expect(provider.isAddress('laptop', ChainId.TRN)).toBe(false)
   })
 })

From cca4db95bbc007a9dd1418b9cccbbe802b9f94ea Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 15:02:24 +0200
Subject: [PATCH 06/24] test(bitcoin): read a Bitcoin balance, not Polygon
 tokens, in the integration spec

---
 .../src/actions/getBitcoinBalance.int.spec.ts              | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.int.spec.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.int.spec.ts
index 72ef0adcb..5fdddb604 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.int.spec.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.int.spec.ts
@@ -50,15 +50,12 @@ describe('getBitcoinBalance integration tests', () => {
     }
   }
 
-  it('should work for ERC20 on POL', {
+  it('should work for BTC on Bitcoin', {
     retry: retryTimes,
     timeout,
   }, async () => {
     const walletAddress = defaultWalletAddress
-    const tokens = [
-      findDefaultToken(CoinKey.USDC, ChainId.POL),
-      findDefaultToken(CoinKey.USDT, ChainId.POL),
-    ]
+    const tokens = [findDefaultToken(CoinKey.BTC, ChainId.BTC)]
 
     await loadAndCompareTokenAmounts(client, walletAddress, tokens)
   })

From 99e862096140f8bc47ac9d702fcf3228ada1fc3e Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 17:55:05 +0200
Subject: [PATCH 07/24] fix(bitcoin): give the Bitcoin balance to BTC tokens
 only in a mixed list

---
 .../src/actions/getBitcoinBalance.ts               | 14 ++++++++------
 .../src/actions/getBitcoinBalance.unit.spec.ts     | 14 ++++++++++++++
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
index 8e54ed355..6c2a0bcfc 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
@@ -22,7 +22,9 @@ export const getBitcoinBalance = async (
   }
   // The client reads Bitcoin only. Another UTXO chain, such as ZEC, shares this
   // provider but not its balances, so its amount stays unknown, not zero.
-  if (chainId !== ChainId.BTC) {
+  const isBitcoinToken = (token: Token): boolean =>
+    token.chainId === ChainId.BTC
+  if (!tokens.some(isBitcoinToken)) {
     return tokens.map((token) => ({ ...token }))
   }
   const bigmiClient = await getBitcoinPublicClient(client, ChainId.BTC)
@@ -43,9 +45,9 @@ export const getBitcoinBalance = async (
     }))
   }
 
-  return tokens.map((token) => ({
-    ...token,
-    amount: balance.value,
-    blockNumber,
-  }))
+  return tokens.map((token) =>
+    isBitcoinToken(token)
+      ? { ...token, amount: balance.value, blockNumber }
+      : { ...token }
+  )
 }
diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
index 22978cf08..71493703a 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
@@ -48,4 +48,18 @@ describe('getBitcoinBalance', () => {
     expect(balance.symbol).toBe('ZEC')
     expect(mocks.getBitcoinPublicClient).not.toHaveBeenCalled()
   })
+
+  it('gives the Bitcoin balance to BTC tokens only in a mixed list', async () => {
+    vi.spyOn(console, 'warn').mockImplementation(() => {})
+    for (const tokens of [
+      [nativeToken(ChainId.BTC, 'BTC'), nativeToken(ChainId.ZEC, 'ZEC')],
+      [nativeToken(ChainId.ZEC, 'ZEC'), nativeToken(ChainId.BTC, 'BTC')],
+    ]) {
+      const balances = await getBitcoinBalance(client, walletAddress, tokens)
+      const bySymbol = Object.fromEntries(
+        balances.map((balance) => [balance.symbol, balance.amount])
+      )
+      expect(bySymbol).toEqual({ BTC: 1234n, ZEC: undefined })
+    }
+  })
 })

From c7c61f22ce96f2cfa6dce1801e9bd09cc4af50af Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 17:55:09 +0200
Subject: [PATCH 08/24] docs(sdk): state what isAddress answers without a chain
 ID

---
 packages/sdk/src/types/core.ts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/packages/sdk/src/types/core.ts b/packages/sdk/src/types/core.ts
index f28b1b55d..6b42b26d4 100644
--- a/packages/sdk/src/types/core.ts
+++ b/packages/sdk/src/types/core.ts
@@ -92,8 +92,9 @@ export type RPCUrls = Partial<Record<ChainId, string[]>>
 export interface SDKProvider {
   readonly type: ChainType
   /**
-   * Validates a wallet address. Without `chainId`, the provider accepts any
-   * address format of its ecosystem, as before. `chainId`, when given, is a
+   * Validates a wallet address. Without `chainId`, the provider answers as
+   * before, which may not cover every chain of its ecosystem: the UTXO
+   * provider accepts Bitcoin formats only. `chainId`, when given, is a
    * chain of this provider's ecosystem: a provider whose chains share one
    * address format may ignore it; a provider whose chains differ accepts only
    * that chain's format and refuses a chain it does not know. Never forward

From 11cfe3d8a7e3bd7e9400a24f804515fcbc4c025a Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 17:55:13 +0200
Subject: [PATCH 09/24] fix(bitcoin): decode Base58Check with named imports
 that work in both builds

bs58check exports only a default, which the CommonJS build resolved to the
whole exports object, so isAddress(t1, ChainId.ZEC) threw for CommonJS users.
@scure/base and @noble/hashes ship named exports for both builds.
---
 packages/sdk-provider-bitcoin/package.json       |  5 +++--
 .../src/utils/zcashAddress.ts                    | 16 ++++++++++++++--
 pnpm-lock.yaml                                   |  9 ++++++---
 3 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/packages/sdk-provider-bitcoin/package.json b/packages/sdk-provider-bitcoin/package.json
index 068ebb8a9..dc7bb5b7c 100644
--- a/packages/sdk-provider-bitcoin/package.json
+++ b/packages/sdk-provider-bitcoin/package.json
@@ -47,9 +47,10 @@
     "@bigmi/core": "^0.9.2",
     "@bitcoinerlab/secp256k1": "^2.0.0",
     "@lifi/sdk": "workspace:*",
+    "@noble/hashes": "^1.8.0",
+    "@scure/base": "^1.2.6",
     "bech32": "^2.0.0",
-    "bitcoinjs-lib": "^7.0.2",
-    "bs58check": "^4.0.0"
+    "bitcoinjs-lib": "^7.0.2"
   },
   "devDependencies": {
     "@lifi/data-types": "^7.1.6",
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
index 981429392..d55028057 100644
--- a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
+++ b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
@@ -1,5 +1,6 @@
+import { sha256 } from '@noble/hashes/sha2'
+import { createBase58check } from '@scure/base'
 import { type BechLib, bech32, bech32m } from 'bech32'
-import bs58check from 'bs58check'
 
 /** The mainnet Zcash address kinds, named by the receiver they encode. */
 export type ZcashAddressKind = 'p2pkh' | 'p2sh' | 'tex' | 'sapling' | 'unified'
@@ -18,10 +19,21 @@ const bech32LengthLimit = 1024
 // A transparent address decodes to a 2-byte version prefix and a 20-byte hash.
 const transparentPayloadLength = 22
 
+const base58check = createBase58check(sha256)
+
+/** The payload of a Base58Check string, or `undefined` for a bad checksum or alphabet. */
+const decodeBase58check = (value: string): Uint8Array | undefined => {
+  try {
+    return base58check.decode(value)
+  } catch {
+    return undefined
+  }
+}
+
 const parseTransparentAddress = (
   address: string
 ): ZcashAddressKind | undefined => {
-  const payload = bs58check.decodeUnsafe(address)
+  const payload = decodeBase58check(address)
   if (payload?.length !== transparentPayloadLength || payload[0] !== 0x1c) {
     return undefined
   }
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f57d0fe89..509eb1471 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -252,15 +252,18 @@ importers:
       '@lifi/sdk':
         specifier: workspace:*
         version: link:../sdk
+      '@noble/hashes':
+        specifier: ^1.8.0
+        version: 1.8.0
+      '@scure/base':
+        specifier: ^1.2.6
+        version: 1.2.6
       bech32:
         specifier: ^2.0.0
         version: 2.0.0
       bitcoinjs-lib:
         specifier: ^7.0.2
         version: 7.0.2(typescript@7.0.2)
-      bs58check:
-        specifier: ^4.0.0
-        version: 4.0.0
     devDependencies:
       '@lifi/data-types':
         specifier: ^7.1.6

From 3feaf803385d44906f8f9ca054357905aa8b4ddf Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 18:10:02 +0200
Subject: [PATCH 10/24] refactor(bitcoin): check only the transparent Zcash
 formats a route accepts

---
 .changeset/zcash-destination-address.md       |  2 +-
 .../src/utils/zcashAddress.ts                 | 93 +++----------------
 .../src/utils/zcashAddress.unit.spec.ts       | 52 +++--------
 3 files changed, 26 insertions(+), 121 deletions(-)

diff --git a/.changeset/zcash-destination-address.md b/.changeset/zcash-destination-address.md
index bfc65346b..7bb48cbac 100644
--- a/.changeset/zcash-destination-address.md
+++ b/.changeset/zcash-destination-address.md
@@ -2,4 +2,4 @@
 '@lifi/sdk-provider-bitcoin': minor
 ---
 
-`BitcoinProvider.isAddress(address, ChainId.ZEC)` validates a Zcash receiver with its checksum. Transparent `t1` and `t3` addresses are accepted; TEX (`tex1`), Sapling (`zs1`) and unified (`u1`) addresses are recognised and refused until the API supports them. Any UTXO chain other than BTC and ZEC is refused, so a Bitcoin address no longer passes as the receiver of a chain whose format the provider does not know. `getBitcoinBalance` now leaves the amount of a non-BTC token unknown instead of reporting the Bitcoin balance for it.
+`BitcoinProvider.isAddress(address, ChainId.ZEC)` validates a Zcash receiver with its checksum. Transparent `t1` and `t3` addresses are accepted; TEX (`tex1`), Sapling (`zs1`) and unified (`u1`) addresses are refused until the API supports them. Any UTXO chain other than BTC and ZEC is refused, so a Bitcoin address no longer passes as the receiver of a chain whose format the provider does not know. `getBitcoinBalance` now leaves the amount of a non-BTC token unknown instead of reporting the Bitcoin balance for it.
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
index d55028057..751e854cc 100644
--- a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
+++ b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
@@ -1,89 +1,24 @@
 import { sha256 } from '@noble/hashes/sha2'
 import { createBase58check } from '@scure/base'
-import { type BechLib, bech32, bech32m } from 'bech32'
 
-/** The mainnet Zcash address kinds, named by the receiver they encode. */
-export type ZcashAddressKind = 'p2pkh' | 'p2sh' | 'tex' | 'sapling' | 'unified'
+const base58check = createBase58check(sha256)
 
 /**
- * The kinds a LI.FI route may send to. The API handles transparent receivers
- * only; add a kind here once the backend confirms it.
+ * Whether `address` is a mainnet transparent Zcash address (`t1` P2PKH or `t3`
+ * P2SH) with a valid checksum. The API handles transparent receivers only, so
+ * TEX, Sapling and unified addresses, and testnet forms, return `false`.
  */
-export const acceptedZcashAddressKinds: ReadonlySet<ZcashAddressKind> =
-  new Set<ZcashAddressKind>(['p2pkh', 'p2sh'])
-
-// Unified addresses outgrow Bech32's default 90-character limit: the longest
-// official test vector (zcash-test-vectors, unified_address.json) has 509.
-const bech32LengthLimit = 1024
-
-// A transparent address decodes to a 2-byte version prefix and a 20-byte hash.
-const transparentPayloadLength = 22
-
-const base58check = createBase58check(sha256)
-
-/** The payload of a Base58Check string, or `undefined` for a bad checksum or alphabet. */
-const decodeBase58check = (value: string): Uint8Array | undefined => {
+export const isZcashAddress = (address: string): boolean => {
+  let payload: Uint8Array
   try {
-    return base58check.decode(value)
+    payload = base58check.decode(address)
   } catch {
-    return undefined
-  }
-}
-
-const parseTransparentAddress = (
-  address: string
-): ZcashAddressKind | undefined => {
-  const payload = decodeBase58check(address)
-  if (payload?.length !== transparentPayloadLength || payload[0] !== 0x1c) {
-    return undefined
-  }
-  if (payload[1] === 0xb8) {
-    return 'p2pkh'
+    return false
   }
-  if (payload[1] === 0xbd) {
-    return 'p2sh'
-  }
-  return undefined
-}
-
-interface Bech32Kind {
-  kind: ZcashAddressKind
-  prefix: string
-  encoding: BechLib
-  /** Unified addresses are F4Jumbled, so only their checksum is checked. */
-  payloadLength?: number
-}
-
-const bech32Kinds: Bech32Kind[] = [
-  { kind: 'tex', prefix: 'tex', encoding: bech32m, payloadLength: 20 },
-  { kind: 'sapling', prefix: 'zs', encoding: bech32, payloadLength: 43 },
-  { kind: 'unified', prefix: 'u', encoding: bech32m },
-]
-
-const parseBech32Address = (address: string): ZcashAddressKind | undefined =>
-  bech32Kinds.find(({ prefix, encoding, payloadLength }) => {
-    const decoded = encoding.decodeUnsafe(address, bech32LengthLimit)
-    if (decoded?.prefix !== prefix) {
-      return false
-    }
-    const payload = encoding.fromWordsUnsafe(decoded.words)
-    return (
-      payload !== undefined &&
-      (payloadLength === undefined || payload.length === payloadLength)
-    )
-  })?.kind
-
-/**
- * Decodes a mainnet Zcash address and verifies its checksum. A testnet address,
- * or any other version or prefix, returns `undefined`.
- */
-export const parseZcashAddress = (
-  address: string
-): ZcashAddressKind | undefined =>
-  parseTransparentAddress(address) ?? parseBech32Address(address)
-
-/** Whether `address` is a Zcash address a LI.FI route may send to. */
-export const isZcashAddress = (address: string): boolean => {
-  const kind = parseZcashAddress(address)
-  return kind !== undefined && acceptedZcashAddressKinds.has(kind)
+  // A 2-byte version prefix (0x1CB8 or 0x1CBD) and a 20-byte hash.
+  return (
+    payload.length === 22 &&
+    payload[0] === 0x1c &&
+    (payload[1] === 0xb8 || payload[1] === 0xbd)
+  )
 }
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts
index 8c162087c..3f88ec269 100644
--- a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts
+++ b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts
@@ -1,9 +1,5 @@
 import { describe, expect, it } from 'vitest'
-import {
-  acceptedZcashAddressKinds,
-  isZcashAddress,
-  parseZcashAddress,
-} from './zcashAddress.js'
+import { isZcashAddress } from './zcashAddress.js'
 
 // Sources: ZIP 320 (t1 and its TEX form), ZIP 214 (t3), zcash-test-vectors
 // unified_address.json (u1, and the Sapling raw address of row 0 encoded as zs1).
@@ -14,59 +10,33 @@ const sapling =
   'zs1mrhc9y7jdh5r9ece8u5khgvj9kg0zgkxzdduyv0whkg7lkcrkx5xqem3e48avjq9wn2rukydkwn'
 const unified =
   'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf'
-// The longest entry in unified_address.json: past Bech32's default 90-character limit.
-const unifiedLongest =
-  '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'
 // The t1 above with its last character changed: the checksum no longer matches.
 const t1WithBadChecksum = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yD'
 // Testnet forms of the same hash: version 0x1D25 and HRP `textest`.
 const testnetTransparent = 'tmMcWbZU8t39htCR1fQRfRSHtkW4p3Ax5Se'
 const testnetTex = 'textest1s2rt77ggv6q989lr49rkgzmh5slsksa90ej7wz'
-const bitcoinSegwit = 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
-const bitcoinLegacy = '1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2'
 
-describe('parseZcashAddress', () => {
+describe('isZcashAddress', () => {
   it.each([
     ['p2pkh', t1],
     ['p2sh', t3],
-    ['tex', tex],
-    ['sapling', sapling],
-    ['unified', unified],
-    ['unified', unifiedLongest],
-  ])('decodes a %s address', (kind, address) => {
-    expect(parseZcashAddress(address)).toBe(kind)
+  ])('accepts a %s address', (_, address) => {
+    expect(isZcashAddress(address)).toBe(true)
   })
 
   it.each([
+    ['a TEX address', tex],
+    ['a Sapling address', sapling],
+    ['a unified address', unified],
     ['a corrupted checksum', t1WithBadChecksum],
     ['a testnet transparent address', testnetTransparent],
     ['a testnet TEX address', testnetTex],
-    ['a Bitcoin segwit address', bitcoinSegwit],
-    ['a Bitcoin legacy address', bitcoinLegacy],
+    ['a Bitcoin segwit address', 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'],
+    ['a Bitcoin legacy address', '1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2'],
     ['an EVM address', '0xB095274743941e953c746F9C228DA9c18Bb6ec29'],
     ['an empty string', ''],
     ['free text', 'not-an-address'],
-  ])('rejects %s', (_, address) => {
-    expect(parseZcashAddress(address)).toBeUndefined()
-  })
-})
-
-describe('isZcashAddress', () => {
-  it('accepts only the transparent kinds a route may send to', () => {
-    expect([...acceptedZcashAddressKinds].sort()).toEqual(['p2pkh', 'p2sh'])
-    expect(isZcashAddress(t1)).toBe(true)
-    expect(isZcashAddress(t3)).toBe(true)
-  })
-
-  it('refuses kinds the backend does not handle yet', () => {
-    expect(isZcashAddress(tex)).toBe(false)
-    expect(isZcashAddress(sapling)).toBe(false)
-    expect(isZcashAddress(unified)).toBe(false)
-  })
-
-  it('refuses a corrupted checksum and addresses of other chains', () => {
-    expect(isZcashAddress(t1WithBadChecksum)).toBe(false)
-    expect(isZcashAddress(bitcoinSegwit)).toBe(false)
-    expect(isZcashAddress(bitcoinLegacy)).toBe(false)
+  ])('refuses %s', (_, address) => {
+    expect(isZcashAddress(address)).toBe(false)
   })
 })

From 8ef92d392dd641148691bc406ddf98da27ead7fe Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 18:10:06 +0200
Subject: [PATCH 11/24] fix(bitcoin): keep the Bitcoin block number off non-BTC
 tokens when the RPC fails

---
 .../src/actions/getBitcoinBalance.ts             | 16 ++++------------
 .../src/actions/getBitcoinBalance.unit.spec.ts   |  3 ++-
 2 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
index 6c2a0bcfc..4e8c0344e 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
@@ -35,19 +35,11 @@ export const getBitcoinBalance = async (
 
   const blockNumber =
     blockCount.status === 'fulfilled' ? BigInt(blockCount.value) : 0n
-
-  if (balance.status !== 'fulfilled') {
-    // RPC failed — leave amount undefined so callers can distinguish
-    // an unknown balance from a known zero.
-    return tokens.map((token) => ({
-      ...token,
-      blockNumber,
-    }))
-  }
+  // RPC failed — leave amount undefined so callers can distinguish
+  // an unknown balance from a known zero.
+  const amount = balance.status === 'fulfilled' ? balance.value : undefined
 
   return tokens.map((token) =>
-    isBitcoinToken(token)
-      ? { ...token, amount: balance.value, blockNumber }
-      : { ...token }
+    isBitcoinToken(token) ? { ...token, amount, blockNumber } : { ...token }
   )
 }
diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
index 71493703a..b42d6f6fe 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
@@ -50,7 +50,7 @@ describe('getBitcoinBalance', () => {
   })
 
   it('gives the Bitcoin balance to BTC tokens only in a mixed list', async () => {
-    vi.spyOn(console, 'warn').mockImplementation(() => {})
+    const warn = vi.spyOn(console, 'warn').mockImplementation(() => {})
     for (const tokens of [
       [nativeToken(ChainId.BTC, 'BTC'), nativeToken(ChainId.ZEC, 'ZEC')],
       [nativeToken(ChainId.ZEC, 'ZEC'), nativeToken(ChainId.BTC, 'BTC')],
@@ -61,5 +61,6 @@ describe('getBitcoinBalance', () => {
       )
       expect(bySymbol).toEqual({ BTC: 1234n, ZEC: undefined })
     }
+    warn.mockRestore()
   })
 })

From bcbb00e874e4b04d6f7cca1c22b611750f08850a Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 18:10:10 +0200
Subject: [PATCH 12/24] docs(sdk): describe isAddress by behaviour, not history

---
 packages/sdk/src/types/core.ts | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/packages/sdk/src/types/core.ts b/packages/sdk/src/types/core.ts
index 6b42b26d4..1db6d0a8e 100644
--- a/packages/sdk/src/types/core.ts
+++ b/packages/sdk/src/types/core.ts
@@ -92,13 +92,10 @@ export type RPCUrls = Partial<Record<ChainId, string[]>>
 export interface SDKProvider {
   readonly type: ChainType
   /**
-   * Validates a wallet address. Without `chainId`, the provider answers as
-   * before, which may not cover every chain of its ecosystem: the UTXO
-   * provider accepts Bitcoin formats only. `chainId`, when given, is a
-   * chain of this provider's ecosystem: a provider whose chains share one
-   * address format may ignore it; a provider whose chains differ accepts only
-   * that chain's format and refuses a chain it does not know. Never forward
-   * `chainId` to a library function whose second parameter means something else.
+   * Validates a wallet address. With `chainId`, a provider whose chains use
+   * different address formats accepts only that chain's format and refuses a
+   * chain it does not know. Never forward `chainId` to a library function whose
+   * second parameter means something else.
    */
   isAddress(address: string, chainId?: ChainId): boolean
   /**

From 8827b318e9f32eb12e627a626625a918b546bf4e Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 18:27:40 +0200
Subject: [PATCH 13/24] refactor(bitcoin): reuse bitcoinjs-lib's sha256 for
 Base58Check

---
 packages/sdk-provider-bitcoin/package.json              | 1 -
 packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts | 4 ++--
 pnpm-lock.yaml                                          | 3 ---
 3 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/packages/sdk-provider-bitcoin/package.json b/packages/sdk-provider-bitcoin/package.json
index dc7bb5b7c..9f446f6db 100644
--- a/packages/sdk-provider-bitcoin/package.json
+++ b/packages/sdk-provider-bitcoin/package.json
@@ -47,7 +47,6 @@
     "@bigmi/core": "^0.9.2",
     "@bitcoinerlab/secp256k1": "^2.0.0",
     "@lifi/sdk": "workspace:*",
-    "@noble/hashes": "^1.8.0",
     "@scure/base": "^1.2.6",
     "bech32": "^2.0.0",
     "bitcoinjs-lib": "^7.0.2"
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
index 751e854cc..a9bcc138e 100644
--- a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
+++ b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
@@ -1,7 +1,7 @@
-import { sha256 } from '@noble/hashes/sha2'
 import { createBase58check } from '@scure/base'
+import { crypto } from 'bitcoinjs-lib'
 
-const base58check = createBase58check(sha256)
+const base58check = createBase58check(crypto.sha256)
 
 /**
  * Whether `address` is a mainnet transparent Zcash address (`t1` P2PKH or `t3`
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 509eb1471..3495b0d1e 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -252,9 +252,6 @@ importers:
       '@lifi/sdk':
         specifier: workspace:*
         version: link:../sdk
-      '@noble/hashes':
-        specifier: ^1.8.0
-        version: 1.8.0
       '@scure/base':
         specifier: ^1.2.6
         version: 1.2.6

From 0b7e3b8c63683eb30c45f84f883dff306eb44387 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 23 Sep 2026 18:27:44 +0200
Subject: [PATCH 14/24] chore: drop the changeset for an invisible Ethereum
 provider change

The @lifi/sdk minor bump already re-releases the Ethereum provider.
---
 .changeset/ethereum-is-address-wrapper.md | 5 -----
 1 file changed, 5 deletions(-)
 delete mode 100644 .changeset/ethereum-is-address-wrapper.md

diff --git a/.changeset/ethereum-is-address-wrapper.md b/.changeset/ethereum-is-address-wrapper.md
deleted file mode 100644
index b41cd3378..000000000
--- a/.changeset/ethereum-is-address-wrapper.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-'@lifi/sdk-provider-ethereum': patch
----
-
-`EthereumProvider.isAddress` no longer passes a second argument to viem's `isAddress`, whose second parameter is `options`. Results are unchanged.

From e7c6c201815c324a253271512dd99024c42fca2a Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 14:09:12 +0200
Subject: [PATCH 15/24] feat(sdk): let a provider serve listed chains beside
 the generic provider of its type

---
 .changeset/chain-aware-is-address.md          |  2 ++
 packages/sdk/src/client/createClient.ts       | 13 ++++---
 .../sdk/src/client/createClient.unit.spec.ts  | 32 +++++++++++++++++
 packages/sdk/src/client/findProvider.ts       | 21 +++++++++++
 .../sdk/src/client/findProvider.unit.spec.ts  | 35 +++++++++++++++++++
 packages/sdk/src/index.ts                     |  1 +
 packages/sdk/src/types/core.ts                |  7 +++-
 7 files changed, 106 insertions(+), 5 deletions(-)
 create mode 100644 packages/sdk/src/client/findProvider.ts
 create mode 100644 packages/sdk/src/client/findProvider.unit.spec.ts

diff --git a/.changeset/chain-aware-is-address.md b/.changeset/chain-aware-is-address.md
index 5eedb8ce0..16e0ea406 100644
--- a/.changeset/chain-aware-is-address.md
+++ b/.changeset/chain-aware-is-address.md
@@ -3,3 +3,5 @@
 ---
 
 `SDKProvider.isAddress` accepts an optional `chainId`. Without it, a provider answers as before. With it, a provider whose chains use different address formats accepts only that chain's format and refuses a chain it does not know. A provider must never forward the chain ID to a library function whose second parameter means something else.
+
+A provider can declare the `chainIds` it serves, so a chain-specific provider can sit beside the generic provider of the same chain type. `client.getProvider(type, chainId?)` returns the provider that lists the chain, otherwise the provider of that type that lists no chains; `getProvider(type)` answers as before. The new `findProvider(providers, chainType, chainId?)` applies the same rule to any provider list. `setProviders` replaces only a provider with the same type and the same `chainIds`.
diff --git a/packages/sdk/src/client/createClient.ts b/packages/sdk/src/client/createClient.ts
index 053fc90aa..9036d404f 100644
--- a/packages/sdk/src/client/createClient.ts
+++ b/packages/sdk/src/client/createClient.ts
@@ -8,8 +8,13 @@ import type {
 } from '../types/core.js'
 import { checkPackageUpdates } from '../utils/checkPackageUpdates.js'
 import { name, version } from '../version.js'
+import { findProvider } from './findProvider.js'
 import { getClientStorage } from './getClientStorage.js'
 
+// A provider replaces only one that serves the same chains.
+const providerScope = (provider: SDKProvider): string =>
+  `${provider.type}:${provider.chainIds?.join(',') ?? ''}`
+
 export function createClient(options: SDKConfig): SDKClient {
   if (!options.integrator) {
     throw new Error(
@@ -68,15 +73,15 @@ export function createClient(options: SDKConfig): SDKClient {
     get providers() {
       return _providers
     },
-    getProvider(type: ChainType) {
-      return this.providers.find((provider) => provider.type === type)
+    getProvider(type: ChainType, chainId?: ChainId) {
+      return findProvider(this.providers, type, chainId)
     },
     setProviders(newProviders: SDKProvider[]) {
       const providerMap = new Map(
-        this.providers.map((provider) => [provider.type, provider])
+        this.providers.map((provider) => [providerScope(provider), provider])
       )
       for (const provider of newProviders) {
-        providerMap.set(provider.type, provider)
+        providerMap.set(providerScope(provider), provider)
       }
       _providers = Array.from(providerMap.values())
     },
diff --git a/packages/sdk/src/client/createClient.unit.spec.ts b/packages/sdk/src/client/createClient.unit.spec.ts
index 81e923dd2..80dd2c32c 100644
--- a/packages/sdk/src/client/createClient.unit.spec.ts
+++ b/packages/sdk/src/client/createClient.unit.spec.ts
@@ -197,6 +197,38 @@ describe('createClient', () => {
       expect(client.getProvider(ChainType.EVM)).toBe(evmProvider2)
       expect(client.getProvider(ChainType.SVM)).toBe(solanaProvider)
     })
+
+    it('keeps a chain-specific provider beside the generic one of its type', () => {
+      const bitcoin = UTXO()
+      const zcash = { ...UTXO(), chainIds: [ChainId.ZEC] }
+      const client = createClient({ integrator: 'test-app' })
+
+      client.setProviders([bitcoin, zcash])
+
+      expect(client.providers).toHaveLength(2)
+      expect(client.providers[0]).toBe(bitcoin)
+      expect(client.providers[1]).toBe(zcash)
+      expect(client.getProvider(ChainType.UTXO)).toBe(bitcoin)
+      expect(client.getProvider(ChainType.UTXO, ChainId.BTC)).toBe(bitcoin)
+      expect(client.getProvider(ChainType.UTXO, ChainId.ZEC)).toBe(zcash)
+    })
+
+    it('replaces only the provider that serves the same chains', () => {
+      const bitcoin1 = UTXO()
+      const bitcoin2 = UTXO()
+      const zcash = { ...UTXO(), chainIds: [ChainId.ZEC] }
+      const client = createClient({
+        integrator: 'test-app',
+        providers: [bitcoin1, zcash],
+      })
+
+      client.setProviders([bitcoin2])
+
+      expect(client.providers).toHaveLength(2)
+      expect(client.providers[0]).toBe(bitcoin2)
+      expect(client.providers[1]).toBe(zcash)
+      expect(client.getProvider(ChainType.UTXO, ChainId.ZEC)).toBe(zcash)
+    })
   })
 
   describe('chain management', () => {
diff --git a/packages/sdk/src/client/findProvider.ts b/packages/sdk/src/client/findProvider.ts
new file mode 100644
index 000000000..606663e83
--- /dev/null
+++ b/packages/sdk/src/client/findProvider.ts
@@ -0,0 +1,21 @@
+import type { ChainId, ChainType } from '@lifi/types'
+import type { SDKProvider } from '../types/core.js'
+
+/**
+ * The provider that serves a chain: the one that lists `chainId` in its
+ * `chainIds`, otherwise the provider of `chainType` that lists no chains.
+ */
+export const findProvider = <T extends Pick<SDKProvider, 'type' | 'chainIds'>>(
+  providers: readonly T[],
+  chainType: ChainType,
+  chainId?: ChainId
+): T | undefined =>
+  (chainId === undefined
+    ? undefined
+    : providers.find(
+        (provider) =>
+          provider.type === chainType && provider.chainIds?.includes(chainId)
+      )) ??
+  providers.find(
+    (provider) => provider.type === chainType && !provider.chainIds
+  )
diff --git a/packages/sdk/src/client/findProvider.unit.spec.ts b/packages/sdk/src/client/findProvider.unit.spec.ts
new file mode 100644
index 000000000..0acfe2167
--- /dev/null
+++ b/packages/sdk/src/client/findProvider.unit.spec.ts
@@ -0,0 +1,35 @@
+import { ChainId, ChainType } from '@lifi/types'
+import { describe, expect, it } from 'vitest'
+import { findProvider } from './findProvider.js'
+
+const provider = (type: ChainType, chainIds?: ChainId[]) => ({ type, chainIds })
+
+describe('findProvider', () => {
+  const evm = provider(ChainType.EVM)
+  const bitcoin = provider(ChainType.UTXO)
+  const zcash = provider(ChainType.UTXO, [ChainId.ZEC])
+  const providers = [evm, bitcoin, zcash]
+
+  it('returns the provider that lists the chain', () => {
+    expect(findProvider(providers, ChainType.UTXO, ChainId.ZEC)).toBe(zcash)
+  })
+
+  it('falls back to the provider of the type that lists no chains', () => {
+    expect(findProvider(providers, ChainType.UTXO, ChainId.BTC)).toBe(bitcoin)
+    expect(findProvider(providers, ChainType.UTXO)).toBe(bitcoin)
+    expect(findProvider(providers, ChainType.EVM, ChainId.ARB)).toBe(evm)
+  })
+
+  it('does not depend on the order of the list', () => {
+    expect(findProvider([zcash, bitcoin], ChainType.UTXO)).toBe(bitcoin)
+    expect(findProvider([zcash, bitcoin], ChainType.UTXO, ChainId.ZEC)).toBe(
+      zcash
+    )
+  })
+
+  it('returns undefined when no provider serves the chain', () => {
+    expect(findProvider([zcash], ChainType.UTXO)).toBeUndefined()
+    expect(findProvider([zcash], ChainType.UTXO, ChainId.BTC)).toBeUndefined()
+    expect(findProvider(providers, ChainType.SVM, ChainId.SOL)).toBeUndefined()
+  })
+})
diff --git a/packages/sdk/src/index.ts b/packages/sdk/src/index.ts
index b7f84d9a3..e8f90392d 100644
--- a/packages/sdk/src/index.ts
+++ b/packages/sdk/src/index.ts
@@ -23,6 +23,7 @@ export { actions } from './actions/index.js'
 export { patchContractCalls } from './actions/patchContractCalls.js'
 export { relayTransaction } from './actions/relayTransaction.js'
 export { createClient } from './client/createClient.js'
+export { findProvider } from './client/findProvider.js'
 export { getActionMessage, getSubstatusMessage } from './core/actionMessages.js'
 export { BaseStepExecutionTask } from './core/BaseStepExecutionTask.js'
 export { BaseStepExecutor } from './core/BaseStepExecutor.js'
diff --git a/packages/sdk/src/types/core.ts b/packages/sdk/src/types/core.ts
index 1db6d0a8e..7b6860346 100644
--- a/packages/sdk/src/types/core.ts
+++ b/packages/sdk/src/types/core.ts
@@ -91,6 +91,11 @@ export type RPCUrls = Partial<Record<ChainId, string[]>>
 
 export interface SDKProvider {
   readonly type: ChainType
+  /**
+   * The chains this provider serves. Omit it to serve every chain of `type`
+   * that no other provider lists.
+   */
+  readonly chainIds?: readonly ChainId[]
   /**
    * Validates a wallet address. With `chainId`, a provider whose chains use
    * different address formats accepts only that chain's format and refuses a
@@ -121,7 +126,7 @@ export interface SDKProvider {
 export interface SDKClient {
   config: SDKBaseConfig
   providers: SDKProvider[]
-  getProvider(type: ChainType): SDKProvider | undefined
+  getProvider(type: ChainType, chainId?: ChainId): SDKProvider | undefined
   setProviders(providers: SDKProvider[]): void
   setChains(chains: ExtendedChain[]): void
   getChains(): Promise<ExtendedChain[]>

From f03e2f8113f3531bd221d1d06d3452366a093dec Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 14:10:47 +0200
Subject: [PATCH 16/24] feat(sdk-provider-zcash): add a destination-only Zcash
 provider

---
 .changeset/zcash-provider.md                  |  5 +
 README.md                                     |  9 ++
 packages/sdk-provider-zcash/package.json      | 93 +++++++++++++++++++
 .../sdk-provider-zcash/src/ZcashProvider.ts   | 30 ++++++
 .../src/ZcashProvider.unit.spec.ts            | 63 +++++++++++++
 packages/sdk-provider-zcash/src/index.ts      |  2 +
 .../src/utils/zcashAddress.ts                 | 24 +++++
 .../src/utils/zcashAddress.unit.spec.ts       | 42 +++++++++
 packages/sdk-provider-zcash/src/version.ts    |  2 +
 packages/sdk-provider-zcash/tsconfig.json     | 17 ++++
 .../sdk-provider-zcash/tsconfig.spec.json     | 22 +++++
 packages/sdk-provider-zcash/tsdown.config.ts  | 38 ++++++++
 pnpm-lock.yaml                                | 28 ++++++
 13 files changed, 375 insertions(+)
 create mode 100644 .changeset/zcash-provider.md
 create mode 100644 packages/sdk-provider-zcash/package.json
 create mode 100644 packages/sdk-provider-zcash/src/ZcashProvider.ts
 create mode 100644 packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts
 create mode 100644 packages/sdk-provider-zcash/src/index.ts
 create mode 100644 packages/sdk-provider-zcash/src/utils/zcashAddress.ts
 create mode 100644 packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts
 create mode 100644 packages/sdk-provider-zcash/src/version.ts
 create mode 100644 packages/sdk-provider-zcash/tsconfig.json
 create mode 100644 packages/sdk-provider-zcash/tsconfig.spec.json
 create mode 100644 packages/sdk-provider-zcash/tsdown.config.ts

diff --git a/.changeset/zcash-provider.md b/.changeset/zcash-provider.md
new file mode 100644
index 000000000..c10c60463
--- /dev/null
+++ b/.changeset/zcash-provider.md
@@ -0,0 +1,5 @@
+---
+'@lifi/sdk-provider-zcash': minor
+---
+
+New package. `ZcashProvider()` validates receivers on ZEC, a destination-only chain: transparent `t1` and `t3` addresses with a valid checksum. It serves `ChainId.ZEC` beside `BitcoinProvider`, leaves balances unknown and cannot execute a step.
diff --git a/README.md b/README.md
index 1c3c1fc1b..184752fc2 100644
--- a/README.md
+++ b/README.md
@@ -83,6 +83,13 @@ needs no ecosystem library. To discover and connect browser wallets such as Frei
 xBull, or Lobstr, we recommend
 [Stellar Wallets Kit](https://github.com/Creit-Tech/Stellar-Wallets-Kit).
 
+**Zcash**
+```bash
+pnpm add @lifi/sdk-provider-zcash
+```
+
+ZEC is a destination-only chain: `ZcashProvider` validates transparent `t1` and `t3` receivers and needs no wallet. Register it beside `BitcoinProvider`; it serves ZEC only.
+
 ## Architecture
 
 The LI.FI SDK uses a modular provider architecture:
@@ -134,6 +141,7 @@ import { BitcoinProvider } from '@lifi/sdk-provider-bitcoin'
 import { SuiProvider } from '@lifi/sdk-provider-sui'
 import { TronProvider } from '@lifi/sdk-provider-tron'
 import { StellarProvider } from '@lifi/sdk-provider-stellar'
+import { ZcashProvider } from '@lifi/sdk-provider-zcash'
 
 const client = createClient({
   integrator: 'Your dApp/company name',
@@ -144,6 +152,7 @@ const client = createClient({
     SuiProvider({ /* options */ }),
     TronProvider({ /* options */ }),
     StellarProvider({ /* options */ }),
+    ZcashProvider(),
   ],
 })
 ```
diff --git a/packages/sdk-provider-zcash/package.json b/packages/sdk-provider-zcash/package.json
new file mode 100644
index 000000000..58a0cf5db
--- /dev/null
+++ b/packages/sdk-provider-zcash/package.json
@@ -0,0 +1,93 @@
+{
+  "name": "@lifi/sdk-provider-zcash",
+  "version": "0.0.0",
+  "description": "LI.FI Zcash SDK Provider for Any-to-Any Cross-Chain-Swap",
+  "homepage": "https://github.com/lifinance/sdk",
+  "bugs": {
+    "url": "https://github.com/lifinance/sdk/issues"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/lifinance/sdk.git",
+    "directory": "packages/sdk-provider-zcash"
+  },
+  "license": "Apache-2.0",
+  "author": "Eugene Chybisov <eugene@li.finance>",
+  "type": "module",
+  "sideEffects": false,
+  "main": "./dist/cjs/index.js",
+  "module": "./dist/esm/index.js",
+  "types": "./dist/esm/index.d.ts",
+  "typings": "./dist/esm/index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./dist/esm/index.d.ts",
+      "import": "./dist/esm/index.js",
+      "default": "./dist/cjs/index.js"
+    },
+    "./package.json": "./package.json"
+  },
+  "scripts": {
+    "build": "rm -rf dist && node ../../scripts/version.js && node ../../scripts/build.js && printf '{\"type\":\"commonjs\"}' > ./dist/cjs/package.json && printf '{\"type\":\"module\",\"sideEffects\":false}' > ./dist/esm/package.json",
+    "build:prerelease": "node ../../scripts/prerelease.js && cpy '../../README.md' .",
+    "build:postrelease": "node ../../scripts/postrelease.js && rm -rf *.md",
+    "build:version": "node ../../scripts/version.js",
+    "clean": "rm -rf dist",
+    "coverage": "vitest run --coverage",
+    "test": "vitest --run",
+    "test:cov": "pnpm test --coverage",
+    "test:unit": "pnpm test .unit.spec.ts --passWithNoTests",
+    "check:types": "tsc --noEmit && tsc -p tsconfig.spec.json --noEmit",
+    "check:types:specs": "tsc -p tsconfig.spec.json --noEmit",
+    "check:circular-deps": "madge --circular $(find ./src -name '*.ts')",
+    "check:circular-deps-graph": "madge --circular $(find ./src -name '*.ts') --image graph.svg",
+    "watch": "tsdown --watch"
+  },
+  "dependencies": {
+    "@lifi/sdk": "workspace:*",
+    "@noble/hashes": "^1.8.0",
+    "@scure/base": "^1.2.6"
+  },
+  "devDependencies": {
+    "@vitest/coverage-v8": "^5.0.1",
+    "cpy-cli": "^7.0.0",
+    "madge": "^8.0.0",
+    "typescript": "^7.0.2",
+    "vitest": "^5.0.1"
+  },
+  "publishConfig": {
+    "access": "public"
+  },
+  "files": [
+    "CHANGELOG.md",
+    "dist/**",
+    "!dist/**/*.tsbuildinfo",
+    "src/**/*.ts",
+    "!src/**/*.spec.ts",
+    "!src/**/*.test.ts",
+    "!src/**/*.mock.ts",
+    "!src/**/*.spec.ts",
+    "!src/**/*.handlers.ts",
+    "!src/**/*.tsbuildinfo",
+    "!**/__mocks__/**",
+    "!*.tmp",
+    "!*.env",
+    "!tsconfig.json"
+  ],
+  "keywords": [
+    "swap",
+    "bridge",
+    "bridge-aggregation",
+    "cross-chain",
+    "cross-chain-applications",
+    "cross-chain-bridge",
+    "dapp",
+    "defi",
+    "zcash",
+    "zec",
+    "lifi",
+    "multi-chain",
+    "sdk",
+    "web3"
+  ]
+}
diff --git a/packages/sdk-provider-zcash/src/ZcashProvider.ts b/packages/sdk-provider-zcash/src/ZcashProvider.ts
new file mode 100644
index 000000000..287b72198
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/ZcashProvider.ts
@@ -0,0 +1,30 @@
+import {
+  ChainId,
+  ChainType,
+  LiFiErrorCode,
+  ProviderError,
+  type SDKProvider,
+} from '@lifi/sdk'
+import { isZcashAddress } from './utils/zcashAddress.js'
+
+export function ZcashProvider(): SDKProvider {
+  return {
+    get type() {
+      return ChainType.UTXO
+    },
+    chainIds: [ChainId.ZEC],
+    isAddress: (address, chainId) =>
+      (chainId === undefined || chainId === ChainId.ZEC) &&
+      isZcashAddress(address),
+    resolveAddress: async () => undefined,
+    // No Zcash balance source yet, so every amount stays unknown.
+    getBalance: async (_client, _walletAddress, tokens) =>
+      tokens.map((token) => ({ ...token })),
+    getStepExecutor: async () => {
+      throw new ProviderError(
+        LiFiErrorCode.ProviderUnavailable,
+        'ZEC is a destination-only chain.'
+      )
+    },
+  }
+}
diff --git a/packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts b/packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts
new file mode 100644
index 000000000..d97862c8f
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts
@@ -0,0 +1,63 @@
+import { ChainId, ChainType, type SDKClient, type Token } from '@lifi/sdk'
+import { describe, expect, it } from 'vitest'
+import { ZcashProvider } from './ZcashProvider.js'
+
+const t1 = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
+const t3 = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
+const bitcoin = 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
+const client = {} as SDKClient
+
+describe('ZcashProvider', () => {
+  const provider = ZcashProvider()
+
+  it('serves ZEC as a UTXO chain', () => {
+    expect(provider.type).toBe(ChainType.UTXO)
+    expect(provider.chainIds).toEqual([ChainId.ZEC])
+  })
+
+  it('accepts a transparent Zcash address without a chain and for ZEC', () => {
+    for (const address of [t1, t3]) {
+      expect(provider.isAddress(address)).toBe(true)
+      expect(provider.isAddress(address, ChainId.ZEC)).toBe(true)
+    }
+  })
+
+  it('refuses a Zcash address for any other chain', () => {
+    expect(provider.isAddress(t1, ChainId.BTC)).toBe(false)
+    expect(provider.isAddress(t1, ChainId.ETH)).toBe(false)
+  })
+
+  it('refuses a Bitcoin address', () => {
+    expect(provider.isAddress(bitcoin)).toBe(false)
+    expect(provider.isAddress(bitcoin, ChainId.ZEC)).toBe(false)
+  })
+
+  it('resolves no names', async () => {
+    await expect(
+      provider.resolveAddress('alice.zec', client)
+    ).resolves.toBeUndefined()
+  })
+
+  it('leaves every balance unknown', async () => {
+    const token: Token = {
+      chainId: ChainId.ZEC,
+      address: 'zcash',
+      symbol: 'ZEC',
+      decimals: 8,
+      name: 'Zcash',
+      priceUSD: '0',
+    }
+
+    const [balance] = await provider.getBalance(client, t1, [token])
+
+    expect(balance).toEqual(token)
+    expect(balance).not.toBe(token)
+    expect(balance).not.toHaveProperty('amount')
+  })
+
+  it('cannot execute a step', async () => {
+    await expect(
+      provider.getStepExecutor({ routeId: 'route' })
+    ).rejects.toThrow('ZEC is a destination-only chain.')
+  })
+})
diff --git a/packages/sdk-provider-zcash/src/index.ts b/packages/sdk-provider-zcash/src/index.ts
new file mode 100644
index 000000000..887d7857a
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/index.ts
@@ -0,0 +1,2 @@
+// biome-ignore lint/performance/noBarrelFile: module entrypoint
+export { ZcashProvider } from './ZcashProvider.js'
diff --git a/packages/sdk-provider-zcash/src/utils/zcashAddress.ts b/packages/sdk-provider-zcash/src/utils/zcashAddress.ts
new file mode 100644
index 000000000..751e854cc
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/utils/zcashAddress.ts
@@ -0,0 +1,24 @@
+import { sha256 } from '@noble/hashes/sha2'
+import { createBase58check } from '@scure/base'
+
+const base58check = createBase58check(sha256)
+
+/**
+ * Whether `address` is a mainnet transparent Zcash address (`t1` P2PKH or `t3`
+ * P2SH) with a valid checksum. The API handles transparent receivers only, so
+ * TEX, Sapling and unified addresses, and testnet forms, return `false`.
+ */
+export const isZcashAddress = (address: string): boolean => {
+  let payload: Uint8Array
+  try {
+    payload = base58check.decode(address)
+  } catch {
+    return false
+  }
+  // A 2-byte version prefix (0x1CB8 or 0x1CBD) and a 20-byte hash.
+  return (
+    payload.length === 22 &&
+    payload[0] === 0x1c &&
+    (payload[1] === 0xb8 || payload[1] === 0xbd)
+  )
+}
diff --git a/packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts b/packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts
new file mode 100644
index 000000000..3f88ec269
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts
@@ -0,0 +1,42 @@
+import { describe, expect, it } from 'vitest'
+import { isZcashAddress } from './zcashAddress.js'
+
+// Sources: ZIP 320 (t1 and its TEX form), ZIP 214 (t3), zcash-test-vectors
+// unified_address.json (u1, and the Sapling raw address of row 0 encoded as zs1).
+const t1 = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
+const t3 = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
+const tex = 'tex1s2rt77ggv6q989lr49rkgzmh5slsksa9khdgte'
+const sapling =
+  'zs1mrhc9y7jdh5r9ece8u5khgvj9kg0zgkxzdduyv0whkg7lkcrkx5xqem3e48avjq9wn2rukydkwn'
+const unified =
+  'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf'
+// The t1 above with its last character changed: the checksum no longer matches.
+const t1WithBadChecksum = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yD'
+// Testnet forms of the same hash: version 0x1D25 and HRP `textest`.
+const testnetTransparent = 'tmMcWbZU8t39htCR1fQRfRSHtkW4p3Ax5Se'
+const testnetTex = 'textest1s2rt77ggv6q989lr49rkgzmh5slsksa90ej7wz'
+
+describe('isZcashAddress', () => {
+  it.each([
+    ['p2pkh', t1],
+    ['p2sh', t3],
+  ])('accepts a %s address', (_, address) => {
+    expect(isZcashAddress(address)).toBe(true)
+  })
+
+  it.each([
+    ['a TEX address', tex],
+    ['a Sapling address', sapling],
+    ['a unified address', unified],
+    ['a corrupted checksum', t1WithBadChecksum],
+    ['a testnet transparent address', testnetTransparent],
+    ['a testnet TEX address', testnetTex],
+    ['a Bitcoin segwit address', 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'],
+    ['a Bitcoin legacy address', '1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2'],
+    ['an EVM address', '0xB095274743941e953c746F9C228DA9c18Bb6ec29'],
+    ['an empty string', ''],
+    ['free text', 'not-an-address'],
+  ])('refuses %s', (_, address) => {
+    expect(isZcashAddress(address)).toBe(false)
+  })
+})
diff --git a/packages/sdk-provider-zcash/src/version.ts b/packages/sdk-provider-zcash/src/version.ts
new file mode 100644
index 000000000..70152b5b8
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/version.ts
@@ -0,0 +1,2 @@
+export const name = '@lifi/sdk-provider-zcash'
+export const version = '0.0.0'
diff --git a/packages/sdk-provider-zcash/tsconfig.json b/packages/sdk-provider-zcash/tsconfig.json
new file mode 100644
index 000000000..1e2ed416e
--- /dev/null
+++ b/packages/sdk-provider-zcash/tsconfig.json
@@ -0,0 +1,17 @@
+{
+  "extends": "../../tsconfig.json",
+  "compilerOptions": {
+    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.tsbuildinfo",
+    "composite": true,
+    "sourceMap": true,
+    "rootDir": "./src",
+    "outDir": "./dist"
+  },
+  "include": ["./src/**/*", "./src/**/*.json"],
+  "exclude": [
+    "tests",
+    "./src/**/*.spec.ts",
+    "./src/**/*.mock.ts",
+    "./src/**/*.handlers.ts"
+  ]
+}
diff --git a/packages/sdk-provider-zcash/tsconfig.spec.json b/packages/sdk-provider-zcash/tsconfig.spec.json
new file mode 100644
index 000000000..8de1c4fd6
--- /dev/null
+++ b/packages/sdk-provider-zcash/tsconfig.spec.json
@@ -0,0 +1,22 @@
+{
+  // Type-checks the files `tsconfig.json` excludes: `*.spec.ts`, `*.mock.ts`
+  // and `*.handlers.ts`. Vitest transpiles without type-checking, so without
+  // this config nothing in the repo ever type-checks a test file — which is how
+  // a wrong type assertion can sit in a green test asserting something other
+  // than what it claims.
+  //
+  // Everything else is inherited unchanged, so tests are held to the same
+  // `strict` / `isolatedDeclarations` / `noUnusedLocals` bar as `src`. Only two
+  // things are overridden: `exclude` (to stop dropping the test files) and
+  // `tsBuildInfoFile` (the inherited path is the one `check:types` writes —
+  // sharing it would make the two runs invalidate each other's cache).
+  //
+  // Run with `--noEmit` (see the `check:types:specs` script): a composite
+  // project may not set `noEmit` in its config, only on the command line.
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.spec.tsbuildinfo"
+  },
+  "include": ["./src/**/*", "./src/**/*.json"],
+  "exclude": ["tests"]
+}
diff --git a/packages/sdk-provider-zcash/tsdown.config.ts b/packages/sdk-provider-zcash/tsdown.config.ts
new file mode 100644
index 000000000..20d8edde2
--- /dev/null
+++ b/packages/sdk-provider-zcash/tsdown.config.ts
@@ -0,0 +1,38 @@
+import { defineConfig } from 'tsdown'
+
+const entry = [
+  'src/**/*.ts',
+  '!src/**/*.spec.ts',
+  '!src/**/*.test.ts',
+  '!src/**/*.mock.ts',
+  '!src/**/*.handlers.ts',
+]
+
+const shared = {
+  unbundle: true,
+  target: 'es2022' as const,
+  logLevel: 'warn' as const,
+  deps: {
+    skipNodeModulesBundle: true,
+  },
+}
+
+export default defineConfig([
+  {
+    ...shared,
+    entry,
+    outDir: 'dist/esm',
+    format: 'esm',
+    sourcemap: true,
+    dts: { sourcemap: true },
+    outExtensions: () => ({ js: '.js', dts: '.d.ts' }),
+  },
+  {
+    ...shared,
+    entry,
+    outDir: 'dist/cjs',
+    format: 'cjs',
+    sourcemap: true,
+    outExtensions: () => ({ js: '.js' }),
+  },
+])
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 3495b0d1e..7b7ecbf9c 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -433,6 +433,34 @@ importers:
         specifier: ^5.0.3
         version: 5.0.3(@types/node@26.6.3)(@vitest/coverage-v8@5.0.3)(msw@3.0.1(@types/node@26.6.3)(graphql@17.0.2)(supports-color@7.2.0)(typescript@7.0.2)(vite@8.3.1(@types/node@26.6.3)(jiti@2.7.0)(yaml@2.9.1)))(vite@8.3.1(@types/node@26.6.3)(jiti@2.7.0)(yaml@2.9.1))
 
+  packages/sdk-provider-zcash:
+    dependencies:
+      '@lifi/sdk':
+        specifier: workspace:*
+        version: link:../sdk
+      '@noble/hashes':
+        specifier: ^1.8.0
+        version: 1.8.0
+      '@scure/base':
+        specifier: ^1.2.6
+        version: 1.2.6
+    devDependencies:
+      '@vitest/coverage-v8':
+        specifier: ^5.0.1
+        version: 5.0.1(vitest@5.0.1)
+      cpy-cli:
+        specifier: ^7.0.0
+        version: 7.0.0
+      madge:
+        specifier: ^8.0.0
+        version: 8.0.0(supports-color@7.2.0)(typescript@7.0.2)
+      typescript:
+        specifier: ^7.0.2
+        version: 7.0.2
+      vitest:
+        specifier: ^5.0.1
+        version: 5.0.1(@types/node@26.6.2)(@vitest/coverage-v8@5.0.1)(msw@2.15.0(@types/node@26.6.2)(typescript@7.0.2))(vite@8.3.0(@types/node@26.6.2)(jiti@2.7.0)(yaml@2.9.1))
+
 packages:
 
   '@0no-co/graphql.web@1.3.4':

From a310c0b79f3238e6fe909bc89a258260e42438d2 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 14:11:52 +0200
Subject: [PATCH 17/24] refactor(sdk-provider-bitcoin): leave Zcash to its own
 provider

---
 .changeset/bitcoin-known-chains-only.md       |  5 +++
 .changeset/zcash-destination-address.md       |  5 ---
 packages/sdk-provider-bitcoin/package.json    |  1 -
 .../src/BitcoinProvider.ts                    | 19 ++------
 .../src/BitcoinProvider.unit.spec.ts          | 45 +++++++++++--------
 .../src/actions/getBitcoinBalance.ts          |  3 +-
 packages/sdk-provider-bitcoin/src/types.ts    |  3 +-
 .../src/utils/zcashAddress.ts                 | 24 ----------
 .../src/utils/zcashAddress.unit.spec.ts       | 42 -----------------
 pnpm-lock.yaml                                |  3 --
 10 files changed, 39 insertions(+), 111 deletions(-)
 create mode 100644 .changeset/bitcoin-known-chains-only.md
 delete mode 100644 .changeset/zcash-destination-address.md
 delete mode 100644 packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
 delete mode 100644 packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts

diff --git a/.changeset/bitcoin-known-chains-only.md b/.changeset/bitcoin-known-chains-only.md
new file mode 100644
index 000000000..b32bce9d5
--- /dev/null
+++ b/.changeset/bitcoin-known-chains-only.md
@@ -0,0 +1,5 @@
+---
+'@lifi/sdk-provider-bitcoin': minor
+---
+
+`BitcoinProvider.isAddress(address, chainId)` refuses every UTXO chain other than BTC, so a Bitcoin address never passes as the receiver of a chain whose format the provider does not know; ZEC receivers are validated by `@lifi/sdk-provider-zcash`. `getBitcoinBalance` leaves the amount of a non-BTC token unknown instead of reporting the Bitcoin balance for it. `isBitcoinProvider` no longer matches another UTXO provider, such as `ZcashProvider`.
diff --git a/.changeset/zcash-destination-address.md b/.changeset/zcash-destination-address.md
deleted file mode 100644
index 7bb48cbac..000000000
--- a/.changeset/zcash-destination-address.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-'@lifi/sdk-provider-bitcoin': minor
----
-
-`BitcoinProvider.isAddress(address, ChainId.ZEC)` validates a Zcash receiver with its checksum. Transparent `t1` and `t3` addresses are accepted; TEX (`tex1`), Sapling (`zs1`) and unified (`u1`) addresses are refused until the API supports them. Any UTXO chain other than BTC and ZEC is refused, so a Bitcoin address no longer passes as the receiver of a chain whose format the provider does not know. `getBitcoinBalance` now leaves the amount of a non-BTC token unknown instead of reporting the Bitcoin balance for it.
diff --git a/packages/sdk-provider-bitcoin/package.json b/packages/sdk-provider-bitcoin/package.json
index 9f446f6db..59ee451dc 100644
--- a/packages/sdk-provider-bitcoin/package.json
+++ b/packages/sdk-provider-bitcoin/package.json
@@ -47,7 +47,6 @@
     "@bigmi/core": "^0.9.2",
     "@bitcoinerlab/secp256k1": "^2.0.0",
     "@lifi/sdk": "workspace:*",
-    "@scure/base": "^1.2.6",
     "bech32": "^2.0.0",
     "bitcoinjs-lib": "^7.0.2"
   },
diff --git a/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts b/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts
index 5630c40b6..a60f5ca6b 100644
--- a/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts
+++ b/packages/sdk-provider-bitcoin/src/BitcoinProvider.ts
@@ -4,22 +4,11 @@ import { getBitcoinBalance } from './actions/getBitcoinBalance.js'
 import { resolveBitcoinAddress } from './actions/resolveBitcoinAddress.js'
 import { BitcoinStepExecutor } from './core/BitcoinStepExecutor.js'
 import type { BitcoinProviderOptions, BitcoinSDKProvider } from './types.js'
-import { isZcashAddress } from './utils/zcashAddress.js'
 
-// Each UTXO chain has its own address format. A chain this provider does not
-// know is refused, so a Bitcoin address never passes as its receiver. The chain
-// ID must not reach bigmi, which reads a second argument as a network.
-const isAddress = (address: string, chainId?: ChainId): boolean => {
-  switch (chainId) {
-    case undefined:
-    case ChainId.BTC:
-      return isUTXOAddress(address)
-    case ChainId.ZEC:
-      return isZcashAddress(address)
-    default:
-      return false
-  }
-}
+// Each UTXO chain has its own address format, so any chain but BTC is refused.
+// The chain ID must not reach bigmi, which reads a second argument as a network.
+const isAddress = (address: string, chainId?: ChainId): boolean =>
+  (chainId === undefined || chainId === ChainId.BTC) && isUTXOAddress(address)
 
 export function BitcoinProvider(
   options?: BitcoinProviderOptions
diff --git a/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts b/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts
index 6cf00326b..71d8cd911 100644
--- a/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts
+++ b/packages/sdk-provider-bitcoin/src/BitcoinProvider.unit.spec.ts
@@ -1,6 +1,7 @@
-import { ChainId, ChainType } from '@lifi/sdk'
+import { ChainId, ChainType, type SDKProvider } from '@lifi/sdk'
 import { describe, expect, it, vi } from 'vitest'
 import { BitcoinProvider } from './BitcoinProvider.js'
+import { isBitcoinProvider } from './types.js'
 
 describe('BitcoinProvider', () => {
   it('should create provider with default options', () => {
@@ -58,9 +59,6 @@ describe('BitcoinProvider', () => {
     const bitcoinSegwit = 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
     const bitcoinLegacy = '1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2'
     const zcashP2pkh = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
-    const zcashP2sh = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
-    const zcashUnified =
-      'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf'
 
     it('keeps today’s answer without a chain ID and for Bitcoin', () => {
       for (const address of [
@@ -77,23 +75,34 @@ describe('BitcoinProvider', () => {
       expect(provider.isAddress(zcashP2pkh)).toBe(false)
     })
 
-    it('accepts only transparent Zcash addresses for ZEC', () => {
-      expect(provider.isAddress(zcashP2pkh, ChainId.ZEC)).toBe(true)
-      expect(provider.isAddress(zcashP2sh, ChainId.ZEC)).toBe(true)
-      expect(provider.isAddress(zcashUnified, ChainId.ZEC)).toBe(false)
-    })
-
-    it('refuses a Bitcoin address for ZEC and a Zcash address for BTC', () => {
-      expect(provider.isAddress(bitcoinSegwit, ChainId.ZEC)).toBe(false)
-      expect(provider.isAddress(bitcoinLegacy, ChainId.ZEC)).toBe(false)
-      expect(provider.isAddress(zcashP2pkh, ChainId.BTC)).toBe(false)
-    })
-
-    it('refuses every address for a UTXO chain it does not know', () => {
-      for (const chainId of [ChainId.LTC, ChainId.BCH, ChainId.DGE]) {
+    it('refuses every address for a UTXO chain other than BTC', () => {
+      for (const chainId of [
+        ChainId.ZEC,
+        ChainId.LTC,
+        ChainId.BCH,
+        ChainId.DGE,
+      ]) {
         expect(provider.isAddress(bitcoinSegwit, chainId)).toBe(false)
         expect(provider.isAddress(zcashP2pkh, chainId)).toBe(false)
       }
     })
   })
+
+  describe('isBitcoinProvider', () => {
+    it('matches the Bitcoin provider only', () => {
+      const otherUtxoProvider: SDKProvider = {
+        type: ChainType.UTXO,
+        chainIds: [ChainId.ZEC],
+        isAddress: () => false,
+        resolveAddress: async () => undefined,
+        getBalance: async () => [],
+        getStepExecutor: async () => {
+          throw new Error('Not used.')
+        },
+      }
+
+      expect(isBitcoinProvider(BitcoinProvider())).toBe(true)
+      expect(isBitcoinProvider(otherUtxoProvider)).toBe(false)
+    })
+  })
 })
diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
index 4e8c0344e..0a153775b 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
@@ -20,8 +20,7 @@ export const getBitcoinBalance = async (
       console.warn('Requested tokens have to be on the same chain.')
     }
   }
-  // The client reads Bitcoin only. Another UTXO chain, such as ZEC, shares this
-  // provider but not its balances, so its amount stays unknown, not zero.
+  // The client reads Bitcoin only, so another chain's amount stays unknown, not zero.
   const isBitcoinToken = (token: Token): boolean =>
     token.chainId === ChainId.BTC
   if (!tokens.some(isBitcoinToken)) {
diff --git a/packages/sdk-provider-bitcoin/src/types.ts b/packages/sdk-provider-bitcoin/src/types.ts
index d3c349b31..a21ba4c55 100644
--- a/packages/sdk-provider-bitcoin/src/types.ts
+++ b/packages/sdk-provider-bitcoin/src/types.ts
@@ -24,5 +24,6 @@ export interface BitcoinSDKProvider extends SDKProvider {
 export function isBitcoinProvider(
   provider: SDKProvider
 ): provider is BitcoinSDKProvider {
-  return provider.type === ChainType.UTXO
+  // Other UTXO providers, such as Zcash, share the type but take no options.
+  return provider.type === ChainType.UTXO && 'setOptions' in provider
 }
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
deleted file mode 100644
index a9bcc138e..000000000
--- a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.ts
+++ /dev/null
@@ -1,24 +0,0 @@
-import { createBase58check } from '@scure/base'
-import { crypto } from 'bitcoinjs-lib'
-
-const base58check = createBase58check(crypto.sha256)
-
-/**
- * Whether `address` is a mainnet transparent Zcash address (`t1` P2PKH or `t3`
- * P2SH) with a valid checksum. The API handles transparent receivers only, so
- * TEX, Sapling and unified addresses, and testnet forms, return `false`.
- */
-export const isZcashAddress = (address: string): boolean => {
-  let payload: Uint8Array
-  try {
-    payload = base58check.decode(address)
-  } catch {
-    return false
-  }
-  // A 2-byte version prefix (0x1CB8 or 0x1CBD) and a 20-byte hash.
-  return (
-    payload.length === 22 &&
-    payload[0] === 0x1c &&
-    (payload[1] === 0xb8 || payload[1] === 0xbd)
-  )
-}
diff --git a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts b/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts
deleted file mode 100644
index 3f88ec269..000000000
--- a/packages/sdk-provider-bitcoin/src/utils/zcashAddress.unit.spec.ts
+++ /dev/null
@@ -1,42 +0,0 @@
-import { describe, expect, it } from 'vitest'
-import { isZcashAddress } from './zcashAddress.js'
-
-// Sources: ZIP 320 (t1 and its TEX form), ZIP 214 (t3), zcash-test-vectors
-// unified_address.json (u1, and the Sapling raw address of row 0 encoded as zs1).
-const t1 = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
-const t3 = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
-const tex = 'tex1s2rt77ggv6q989lr49rkgzmh5slsksa9khdgte'
-const sapling =
-  'zs1mrhc9y7jdh5r9ece8u5khgvj9kg0zgkxzdduyv0whkg7lkcrkx5xqem3e48avjq9wn2rukydkwn'
-const unified =
-  'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf'
-// The t1 above with its last character changed: the checksum no longer matches.
-const t1WithBadChecksum = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yD'
-// Testnet forms of the same hash: version 0x1D25 and HRP `textest`.
-const testnetTransparent = 'tmMcWbZU8t39htCR1fQRfRSHtkW4p3Ax5Se'
-const testnetTex = 'textest1s2rt77ggv6q989lr49rkgzmh5slsksa90ej7wz'
-
-describe('isZcashAddress', () => {
-  it.each([
-    ['p2pkh', t1],
-    ['p2sh', t3],
-  ])('accepts a %s address', (_, address) => {
-    expect(isZcashAddress(address)).toBe(true)
-  })
-
-  it.each([
-    ['a TEX address', tex],
-    ['a Sapling address', sapling],
-    ['a unified address', unified],
-    ['a corrupted checksum', t1WithBadChecksum],
-    ['a testnet transparent address', testnetTransparent],
-    ['a testnet TEX address', testnetTex],
-    ['a Bitcoin segwit address', 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'],
-    ['a Bitcoin legacy address', '1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2'],
-    ['an EVM address', '0xB095274743941e953c746F9C228DA9c18Bb6ec29'],
-    ['an empty string', ''],
-    ['free text', 'not-an-address'],
-  ])('refuses %s', (_, address) => {
-    expect(isZcashAddress(address)).toBe(false)
-  })
-})
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 7b7ecbf9c..61680ab99 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -252,9 +252,6 @@ importers:
       '@lifi/sdk':
         specifier: workspace:*
         version: link:../sdk
-      '@scure/base':
-        specifier: ^1.2.6
-        version: 1.2.6
       bech32:
         specifier: ^2.0.0
         version: 2.0.0

From 1d3c2efde5ba91c18328e77ed4733e70d22625ef Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 14:41:57 +0200
Subject: [PATCH 18/24] fix(sdk): scope a provider by its sorted chain list,
 and a generic one by its type

---
 packages/sdk/src/client/createClient.ts       |  7 +++--
 .../sdk/src/client/createClient.unit.spec.ts  | 30 +++++++++++++++++++
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/packages/sdk/src/client/createClient.ts b/packages/sdk/src/client/createClient.ts
index 9036d404f..1727c313a 100644
--- a/packages/sdk/src/client/createClient.ts
+++ b/packages/sdk/src/client/createClient.ts
@@ -11,9 +11,12 @@ import { name, version } from '../version.js'
 import { findProvider } from './findProvider.js'
 import { getClientStorage } from './getClientStorage.js'
 
-// A provider replaces only one that serves the same chains.
+// A provider replaces only one that serves the same chains. A provider that
+// lists no chains keeps the bare type, so even an empty list stays apart.
 const providerScope = (provider: SDKProvider): string =>
-  `${provider.type}:${provider.chainIds?.join(',') ?? ''}`
+  provider.chainIds
+    ? `${provider.type}:${[...provider.chainIds].sort().join(',')}`
+    : provider.type
 
 export function createClient(options: SDKConfig): SDKClient {
   if (!options.integrator) {
diff --git a/packages/sdk/src/client/createClient.unit.spec.ts b/packages/sdk/src/client/createClient.unit.spec.ts
index 80dd2c32c..0b8bd1096 100644
--- a/packages/sdk/src/client/createClient.unit.spec.ts
+++ b/packages/sdk/src/client/createClient.unit.spec.ts
@@ -229,6 +229,36 @@ describe('createClient', () => {
       expect(client.providers[1]).toBe(zcash)
       expect(client.getProvider(ChainType.UTXO, ChainId.ZEC)).toBe(zcash)
     })
+
+    it('keeps the generic provider beside one that lists no chains', () => {
+      const bitcoin = UTXO()
+      const empty = { ...UTXO(), chainIds: [] }
+      const client = createClient({
+        integrator: 'test-app',
+        providers: [bitcoin],
+      })
+
+      client.setProviders([empty])
+
+      expect(client.providers).toHaveLength(2)
+      expect(client.providers[0]).toBe(bitcoin)
+      expect(client.providers[1]).toBe(empty)
+      expect(client.getProvider(ChainType.UTXO)).toBe(bitcoin)
+    })
+
+    it('replaces a provider that lists the same chains in another order', () => {
+      const first = { ...UTXO(), chainIds: [ChainId.ZEC, ChainId.LTC] }
+      const second = { ...UTXO(), chainIds: [ChainId.LTC, ChainId.ZEC] }
+      const client = createClient({
+        integrator: 'test-app',
+        providers: [first],
+      })
+
+      client.setProviders([second])
+
+      expect(client.providers).toHaveLength(1)
+      expect(client.providers[0]).toBe(second)
+    })
   })
 
   describe('chain management', () => {

From 1d2c75de2247905c5e7771ec3b1c7913bb0b8fa6 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 14:42:03 +0200
Subject: [PATCH 19/24] fix(sdk-provider-bitcoin): set no BTC amount when the
 balance request fails

---
 .../src/actions/getBitcoinBalance.ts               |  8 ++++----
 .../src/actions/getBitcoinBalance.unit.spec.ts     | 14 ++++++++++++++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
index 0a153775b..5b23b9fed 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.ts
@@ -34,11 +34,11 @@ export const getBitcoinBalance = async (
 
   const blockNumber =
     blockCount.status === 'fulfilled' ? BigInt(blockCount.value) : 0n
-  // RPC failed — leave amount undefined so callers can distinguish
-  // an unknown balance from a known zero.
-  const amount = balance.status === 'fulfilled' ? balance.value : undefined
+  // A failed request sets no amount, so callers can tell an unknown balance
+  // from a known zero.
+  const amount = balance.status === 'fulfilled' ? { amount: balance.value } : {}
 
   return tokens.map((token) =>
-    isBitcoinToken(token) ? { ...token, amount, blockNumber } : { ...token }
+    isBitcoinToken(token) ? { ...token, ...amount, blockNumber } : { ...token }
   )
 }
diff --git a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
index b42d6f6fe..976323c8a 100644
--- a/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
+++ b/packages/sdk-provider-bitcoin/src/actions/getBitcoinBalance.unit.spec.ts
@@ -63,4 +63,18 @@ describe('getBitcoinBalance', () => {
     }
     warn.mockRestore()
   })
+
+  it('adds no amount for BTC when the balance request fails', async () => {
+    mocks.getBitcoinPublicClient.mockResolvedValue({
+      getBalance: vi.fn().mockRejectedValue(new Error('RPC down')),
+      getBlockCount: vi.fn().mockResolvedValue(900_000),
+    })
+
+    const [balance] = await getBitcoinBalance(client, walletAddress, [
+      nativeToken(ChainId.BTC, 'BTC'),
+    ])
+
+    expect(balance).not.toHaveProperty('amount')
+    expect(balance.blockNumber).toBe(900_000n)
+  })
 })

From 3718594a3d2caa9bd5a7d1b7880a888556b13cc4 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 14:44:07 +0200
Subject: [PATCH 20/24] docs: count the Zcash provider package

---
 CLAUDE.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CLAUDE.md b/CLAUDE.md
index c2abf1c55..3425c3add 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -1,7 +1,7 @@
 # CLAUDE.md
 
 ## Project
-TypeScript monorepo (pnpm workspaces) with 7 packages under `packages/`. `@lifi/sdk`
+TypeScript monorepo (pnpm workspaces) with 8 packages under `packages/`. `@lifi/sdk`
 is the hub; each provider depends on it via `workspace:*` as a **regular** dependency
 (not peer), which resolves to the exact pinned version in published tarballs.
 

From 79626ca2d7a98ad3a9763183bf3ab4e756b3df87 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 15:00:55 +0200
Subject: [PATCH 21/24] docs(changeset): tell custom provider authors to wrap a
 two-parameter isAddress

---
 .changeset/chain-aware-is-address.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.changeset/chain-aware-is-address.md b/.changeset/chain-aware-is-address.md
index 16e0ea406..6f2846dac 100644
--- a/.changeset/chain-aware-is-address.md
+++ b/.changeset/chain-aware-is-address.md
@@ -2,6 +2,6 @@
 '@lifi/sdk': minor
 ---
 
-`SDKProvider.isAddress` accepts an optional `chainId`. Without it, a provider answers as before. With it, a provider whose chains use different address formats accepts only that chain's format and refuses a chain it does not know. A provider must never forward the chain ID to a library function whose second parameter means something else.
+`SDKProvider.isAddress` accepts an optional `chainId`. Without it, a provider answers as before. With it, a provider whose chains use different address formats accepts only that chain's format and refuses a chain it does not know. A provider must never forward the chain ID to a library function whose second parameter means something else. A custom provider that assigns such a function directly as `isAddress`, for example viem's `isAddress` or bigmi's `isUTXOAddress`, no longer type-checks; wrap it in a one-argument function, as `EthereumProvider` and `BitcoinProvider` do.
 
 A provider can declare the `chainIds` it serves, so a chain-specific provider can sit beside the generic provider of the same chain type. `client.getProvider(type, chainId?)` returns the provider that lists the chain, otherwise the provider of that type that lists no chains; `getProvider(type)` answers as before. The new `findProvider(providers, chainType, chainId?)` applies the same rule to any provider list. `setProviders` replaces only a provider with the same type and the same `chainIds`.

From 4f8a495207d21e1e2c601c6f8c4fa2ad54d2e0ec Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Wed, 30 Sep 2026 15:17:26 +0200
Subject: [PATCH 22/24] docs: register the Zcash provider after the Bitcoin
 provider

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 184752fc2..e9465ac2c 100644
--- a/README.md
+++ b/README.md
@@ -88,7 +88,7 @@ xBull, or Lobstr, we recommend
 pnpm add @lifi/sdk-provider-zcash
 ```
 
-ZEC is a destination-only chain: `ZcashProvider` validates transparent `t1` and `t3` receivers and needs no wallet. Register it beside `BitcoinProvider`; it serves ZEC only.
+ZEC is a destination-only chain: `ZcashProvider` validates transparent `t1` and `t3` receivers and needs no wallet. Register it after `BitcoinProvider`; it serves ZEC only.
 
 ## Architecture
 

From 1b774eec1b21c5b8bfab316a288406ce18179df7 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Mon, 5 Oct 2026 13:56:54 +0200
Subject: [PATCH 23/24] chore(sdk-provider-zcash): align the test tooling with
 main

---
 packages/sdk-provider-zcash/package.json | 4 ++--
 pnpm-lock.yaml                           | 8 ++++----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/packages/sdk-provider-zcash/package.json b/packages/sdk-provider-zcash/package.json
index 58a0cf5db..d08b56e8f 100644
--- a/packages/sdk-provider-zcash/package.json
+++ b/packages/sdk-provider-zcash/package.json
@@ -49,11 +49,11 @@
     "@scure/base": "^1.2.6"
   },
   "devDependencies": {
-    "@vitest/coverage-v8": "^5.0.1",
+    "@vitest/coverage-v8": "^5.0.3",
     "cpy-cli": "^7.0.0",
     "madge": "^8.0.0",
     "typescript": "^7.0.2",
-    "vitest": "^5.0.1"
+    "vitest": "^5.0.3"
   },
   "publishConfig": {
     "access": "public"
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 61680ab99..d404c9983 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -443,8 +443,8 @@ importers:
         version: 1.2.6
     devDependencies:
       '@vitest/coverage-v8':
-        specifier: ^5.0.1
-        version: 5.0.1(vitest@5.0.1)
+        specifier: ^5.0.3
+        version: 5.0.3(vitest@5.0.3)
       cpy-cli:
         specifier: ^7.0.0
         version: 7.0.0
@@ -455,8 +455,8 @@ importers:
         specifier: ^7.0.2
         version: 7.0.2
       vitest:
-        specifier: ^5.0.1
-        version: 5.0.1(@types/node@26.6.2)(@vitest/coverage-v8@5.0.1)(msw@2.15.0(@types/node@26.6.2)(typescript@7.0.2))(vite@8.3.0(@types/node@26.6.2)(jiti@2.7.0)(yaml@2.9.1))
+        specifier: ^5.0.3
+        version: 5.0.3(@types/node@26.6.3)(@vitest/coverage-v8@5.0.3)(msw@3.0.1(@types/node@26.6.3)(graphql@17.0.2)(supports-color@7.2.0)(typescript@7.0.2)(vite@8.3.1(@types/node@26.6.3)(jiti@2.7.0)(yaml@2.9.1)))(vite@8.3.1(@types/node@26.6.3)(jiti@2.7.0)(yaml@2.9.1))
 
 packages:
 

From b7870f68c0a5d0cedaae6eb01cbd7efda81a16a9 Mon Sep 17 00:00:00 2001
From: Eugene Chybisov <imchybisov@gmail.com>
Date: Tue, 6 Oct 2026 15:12:44 +0200
Subject: [PATCH 24/24] feat(sdk-provider-zcash): accept unified addresses with
 an Orchard receiver

---
 .changeset/zcash-provider.md                  |   2 +-
 README.md                                     |   2 +-
 .../src/ZcashProvider.unit.spec.ts            |   7 +-
 .../src/utils/unifiedAddress.ts               | 125 +++++++
 .../src/utils/unifiedAddress.unit.spec.ts     |  63 ++++
 .../src/utils/unifiedAddress.vectors.mock.ts  | 333 ++++++++++++++++++
 .../src/utils/zcashAddress.ts                 |  17 +-
 .../src/utils/zcashAddress.unit.spec.ts       |  16 +-
 8 files changed, 549 insertions(+), 16 deletions(-)
 create mode 100644 packages/sdk-provider-zcash/src/utils/unifiedAddress.ts
 create mode 100644 packages/sdk-provider-zcash/src/utils/unifiedAddress.unit.spec.ts
 create mode 100644 packages/sdk-provider-zcash/src/utils/unifiedAddress.vectors.mock.ts

diff --git a/.changeset/zcash-provider.md b/.changeset/zcash-provider.md
index c10c60463..c751515e7 100644
--- a/.changeset/zcash-provider.md
+++ b/.changeset/zcash-provider.md
@@ -2,4 +2,4 @@
 '@lifi/sdk-provider-zcash': minor
 ---
 
-New package. `ZcashProvider()` validates receivers on ZEC, a destination-only chain: transparent `t1` and `t3` addresses with a valid checksum. It serves `ChainId.ZEC` beside `BitcoinProvider`, leaves balances unknown and cannot execute a step.
+New package. `ZcashProvider()` validates receivers on ZEC, a destination-only chain: transparent `t1` and `t3` addresses with a valid checksum, and unified `u1` addresses that decode under ZIP 316 and carry an Orchard receiver, the ones the API pays to a shielded balance. Sapling, TEX and testnet addresses, and a unified address without an Orchard receiver, are refused. It serves `ChainId.ZEC` beside `BitcoinProvider`, leaves balances unknown and cannot execute a step.
diff --git a/README.md b/README.md
index e9465ac2c..da2b40abb 100644
--- a/README.md
+++ b/README.md
@@ -88,7 +88,7 @@ xBull, or Lobstr, we recommend
 pnpm add @lifi/sdk-provider-zcash
 ```
 
-ZEC is a destination-only chain: `ZcashProvider` validates transparent `t1` and `t3` receivers and needs no wallet. Register it after `BitcoinProvider`; it serves ZEC only.
+ZEC is a destination-only chain: `ZcashProvider` validates transparent `t1` and `t3` receivers, and unified `u1` receivers that carry an Orchard receiver, and needs no wallet. Register it after `BitcoinProvider`; it serves ZEC only.
 
 ## Architecture
 
diff --git a/packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts b/packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts
index d97862c8f..b33294160 100644
--- a/packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts
+++ b/packages/sdk-provider-zcash/src/ZcashProvider.unit.spec.ts
@@ -4,6 +4,8 @@ import { ZcashProvider } from './ZcashProvider.js'
 
 const t1 = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
 const t3 = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
+const unified =
+  'u1k9eh52jx5q4y8lw6x208lsep4t6yzwk7mdwz9e6239qywjkqzdcd3al3d64zwnqx296p3klxnash5w2e0elg39qrydxx0s0qz5m2gnt0'
 const bitcoin = 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
 const client = {} as SDKClient
 
@@ -15,8 +17,8 @@ describe('ZcashProvider', () => {
     expect(provider.chainIds).toEqual([ChainId.ZEC])
   })
 
-  it('accepts a transparent Zcash address without a chain and for ZEC', () => {
-    for (const address of [t1, t3]) {
+  it('accepts a transparent or Orchard unified address without a chain and for ZEC', () => {
+    for (const address of [t1, t3, unified]) {
       expect(provider.isAddress(address)).toBe(true)
       expect(provider.isAddress(address, ChainId.ZEC)).toBe(true)
     }
@@ -25,6 +27,7 @@ describe('ZcashProvider', () => {
   it('refuses a Zcash address for any other chain', () => {
     expect(provider.isAddress(t1, ChainId.BTC)).toBe(false)
     expect(provider.isAddress(t1, ChainId.ETH)).toBe(false)
+    expect(provider.isAddress(unified, ChainId.BTC)).toBe(false)
   })
 
   it('refuses a Bitcoin address', () => {
diff --git a/packages/sdk-provider-zcash/src/utils/unifiedAddress.ts b/packages/sdk-provider-zcash/src/utils/unifiedAddress.ts
new file mode 100644
index 000000000..384da68c0
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/utils/unifiedAddress.ts
@@ -0,0 +1,125 @@
+import { blake2b } from '@noble/hashes/blake2b'
+import { bech32m } from '@scure/base'
+
+const ORCHARD = 0x03
+/** Byte length of each receiver typecode the API pays to (ZIP 316). */
+const RECEIVER_LENGTHS: ReadonlyMap<number, number> = new Map([
+  [0x00, 20], // P2PKH
+  [0x01, 20], // P2SH
+  [0x02, 43], // Sapling
+  [ORCHARD, 43],
+])
+// Bech32 caps decoding at 90 characters; a unified address runs to hundreds.
+const BECH32M_LIMIT = 4096
+const MIN_JUMBLED_LENGTH = 48
+// The decoded payload ends with the HRP `u`, zero-padded to 16 bytes.
+const PADDING = Uint8Array.from({ length: 16 }, (_, k) => (k === 0 ? 0x75 : 0))
+const BLAKE2B_MAX_LENGTH = 64
+
+const textEncoder = new TextEncoder()
+
+/** 16-byte BLAKE2b personalization: `UA_F4Jumble_<tag>`, then `i` and `j` as LE u16. */
+const personalization = (tag: 'H' | 'G', i: number, j = 0): Uint8Array => {
+  const bytes = new Uint8Array(16)
+  bytes.set(textEncoder.encode(`UA_F4Jumble_${tag}`))
+  bytes[13] = i
+  bytes[14] = j & 0xff
+  bytes[15] = j >> 8
+  return bytes
+}
+
+const hashH = (i: number, input: Uint8Array, length: number): Uint8Array =>
+  blake2b(input, { dkLen: length, personalization: personalization('H', i) })
+
+const hashG = (i: number, input: Uint8Array, length: number): Uint8Array => {
+  const output = new Uint8Array(length)
+  for (let j = 0; j * BLAKE2B_MAX_LENGTH < length; j++) {
+    const block = blake2b(input, {
+      dkLen: BLAKE2B_MAX_LENGTH,
+      personalization: personalization('G', i, j),
+    })
+    const offset = j * BLAKE2B_MAX_LENGTH
+    output.set(block.subarray(0, length - offset), offset)
+  }
+  return output
+}
+
+const xor = (a: Uint8Array, b: Uint8Array): Uint8Array =>
+  a.map((byte, k) => byte ^ b[k])
+
+/** The inverse of F4Jumble, the Feistel jumble ZIP 316 applies before Bech32m. */
+export const f4JumbleInverse = (jumbled: Uint8Array): Uint8Array => {
+  const leftLength = Math.min(
+    BLAKE2B_MAX_LENGTH,
+    Math.floor(jumbled.length / 2)
+  )
+  const rightLength = jumbled.length - leftLength
+  const c = jumbled.subarray(0, leftLength)
+  const d = jumbled.subarray(leftLength)
+  const y = xor(c, hashH(1, d, leftLength))
+  const x = xor(d, hashG(1, y, rightLength))
+  const a = xor(y, hashH(0, x, leftLength))
+  const b = xor(x, hashG(0, a, rightLength))
+  const raw = new Uint8Array(jumbled.length)
+  raw.set(a)
+  raw.set(b, leftLength)
+  return raw
+}
+
+/**
+ * The typecodes of a decoded receiver list, or `undefined` when a receiver is
+ * not one the API pays to, has another length, breaks the ascending order or
+ * overruns. Every accepted typecode and length fits one CompactSize byte, so a
+ * wider CompactSize can only encode a typecode the API refuses.
+ */
+const receiverTypecodes = (body: Uint8Array): number[] | undefined => {
+  const typecodes: number[] = []
+  for (let offset = 0; offset < body.length; ) {
+    const typecode = body[offset]
+    const length = RECEIVER_LENGTHS.get(typecode)
+    const end = offset + 2 + (length ?? 0)
+    if (
+      length === undefined ||
+      body[offset + 1] !== length ||
+      end > body.length ||
+      typecode <= (typecodes.at(-1) ?? -1)
+    ) {
+      return undefined
+    }
+    typecodes.push(typecode)
+    offset = end
+  }
+  return typecodes
+}
+
+/**
+ * Whether `address` is a mainnet unified address (`u1`) that the API pays to a
+ * shielded balance. It must decode — Bech32m checksum, F4Jumble, padding —
+ * into P2PKH, P2SH, Sapling and Orchard receivers only, each at its length, in
+ * ascending typecode order, with at most one transparent receiver, and one of
+ * them must be Orchard: without it a bridge pays the transparent receiver.
+ */
+export const isOrchardUnifiedAddress = (address: string): boolean => {
+  // The API takes the lowercase form only.
+  if (!address.startsWith('u1')) {
+    return false
+  }
+  const decoded = bech32m.decodeUnsafe(address, BECH32M_LIMIT)
+  if (decoded?.prefix !== 'u') {
+    return false
+  }
+  const jumbled = bech32m.fromWordsUnsafe(decoded.words)
+  if (!jumbled || jumbled.length < MIN_JUMBLED_LENGTH) {
+    return false
+  }
+  const raw = f4JumbleInverse(jumbled)
+  const paddingStart = raw.length - PADDING.length
+  if (PADDING.some((byte, k) => raw[paddingStart + k] !== byte)) {
+    return false
+  }
+  const typecodes = receiverTypecodes(raw.subarray(0, paddingStart)) ?? []
+  return (
+    typecodes.includes(ORCHARD) &&
+    !(typecodes.includes(0x00) && typecodes.includes(0x01))
+  )
+}
diff --git a/packages/sdk-provider-zcash/src/utils/unifiedAddress.unit.spec.ts b/packages/sdk-provider-zcash/src/utils/unifiedAddress.unit.spec.ts
new file mode 100644
index 000000000..55ceb5d2b
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/utils/unifiedAddress.unit.spec.ts
@@ -0,0 +1,63 @@
+import { bech32m } from '@scure/base'
+import { describe, expect, it } from 'vitest'
+import { f4JumbleInverse, isOrchardUnifiedAddress } from './unifiedAddress.js'
+import {
+  f4JumbleVectors,
+  unifiedAddressVectors,
+} from './unifiedAddress.vectors.mock.js'
+
+const hexToBytes = (hex: string): Uint8Array =>
+  Uint8Array.from(hex.match(/../g) ?? [], (byte) => Number.parseInt(byte, 16))
+
+// A Zashi address with one receiver, Orchard.
+const orchardOnly =
+  'u1k9eh52jx5q4y8lw6x208lsep4t6yzwk7mdwz9e6239qywjkqzdcd3al3d64zwnqx296p3klxnash5w2e0elg39qrydxx0s0qz5m2gnt0'
+
+describe('f4JumbleInverse', () => {
+  it.each(f4JumbleVectors)('restores %s', (raw, jumbled) => {
+    expect(f4JumbleInverse(hexToBytes(jumbled))).toEqual(hexToBytes(raw))
+  })
+})
+
+describe('isOrchardUnifiedAddress', () => {
+  it('accepts a unified address with an Orchard receiver only', () => {
+    expect(isOrchardUnifiedAddress(orchardOnly)).toBe(true)
+  })
+
+  it.each(unifiedAddressVectors)(
+    'answers $payable for $address',
+    ({ address, payable }) => {
+      expect(isOrchardUnifiedAddress(address)).toBe(payable)
+    }
+  )
+
+  it('refuses a corrupted checksum', () => {
+    // The last character of the address is `0`; `q` keeps the Bech32 alphabet.
+    expect(isOrchardUnifiedAddress(`${orchardOnly.slice(0, -1)}q`)).toBe(false)
+  })
+
+  it('refuses the uppercase form, which the API does not take', () => {
+    expect(isOrchardUnifiedAddress(orchardOnly.toUpperCase())).toBe(false)
+  })
+
+  it('refuses a testnet unified address', () => {
+    const { words } = bech32m.decode(orchardOnly, 4096)
+    expect(isOrchardUnifiedAddress(bech32m.encode('utest', words, 4096))).toBe(
+      false
+    )
+  })
+
+  it.each([
+    ['a transparent address', 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'],
+    [
+      'a Sapling address',
+      'zs1mrhc9y7jdh5r9ece8u5khgvj9kg0zgkxzdduyv0whkg7lkcrkx5xqem3e48avjq9wn2rukydkwn',
+    ],
+    ['a TEX address', 'tex1s2rt77ggv6q989lr49rkgzmh5slsksa9khdgte'],
+    ['a truncated address', orchardOnly.slice(0, 40)],
+    ['a name', 'u1.eth'],
+    ['an empty string', ''],
+  ])('refuses %s', (_, address) => {
+    expect(isOrchardUnifiedAddress(address)).toBe(false)
+  })
+})
diff --git a/packages/sdk-provider-zcash/src/utils/unifiedAddress.vectors.mock.ts b/packages/sdk-provider-zcash/src/utils/unifiedAddress.vectors.mock.ts
new file mode 100644
index 000000000..156639ccb
--- /dev/null
+++ b/packages/sdk-provider-zcash/src/utils/unifiedAddress.vectors.mock.ts
@@ -0,0 +1,333 @@
+// From zcash/zcash-test-vectors: test-vectors/zcash/unified_address.json and f4jumble.json.
+
+/** Each unified address and whether the API pays it: an Orchard receiver and no unknown typecode. */
+export const unifiedAddressVectors: { address: string; payable: boolean }[] = [
+  {
+    address:
+      'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf',
+    payable: false,
+  },
+  {
+    address:
+      'u1fl5mprj0t9p4jg92hjjy8q5myvwc60c9wv0xachauqpn3c3k4xwzlaueafq27dcg7tzzzaz5jl8tyj93wgs983y0jq0qfhzu6n4r8rakpv5f4gg2lrw4z6pyqqcrcqx04d38yunc6je',
+    payable: false,
+  },
+  {
+    address:
+      'u1qxqf8ctkxlsdh7xdcgkdtyw4mku7dxma8tsz45xd6ttgs322gdk7kazg3sdn52z7na3tzcrzf7lt3xrdtfp9d4pccderalchvvxk8hghduxrky5guzqlw65fmgp6x7aj4k8v5jkgwuw',
+    payable: false,
+  },
+  {
+    address:
+      'u1pg2aaph7jp8rpf6yhsza25722sg5fcn3vaca6ze27hqjw7jvvhhuxkpcg0ge9xh6drsgdkda8qjq5chpehkcpxf87rnjryjqwymdheptpvnljqqrjqzjwkc2ma6hcq666kgwfytxwac8eyex6ndgr6ezte66706e3vaqrd25dzvzkc69kw0jgywtd0cmq52q5lkw6uh7hyvzjse8ksx',
+    payable: true,
+  },
+  {
+    address:
+      'u19mzuf4l37ny393m59v4mxx4t3uyxkh7qpqjdfvlfk9f504cv9w4fpl7cql0kqvssz8jay8mgl8lnrtvg6yzh9pranjj963acc3h2z2qt7007du0lsmdf862dyy40c3wmt0kq35k5z836tfljgzsqtdsccchayfjpygqzkx24l77ga3ngfgskqddyepz8we7ny4ggmt7q48cgvgu57mz',
+    payable: true,
+  },
+  {
+    address:
+      'u1mtxw5nras5glkxz093282sv3n2h8qs7cpxcmmaxj96vtzjzl6rmdaxs4e9es7mxwmd0h3k5wz3ce4ll5g4jz2pn9su4pufq74pxhp4t235n6j7aed3hh8ss7pf3sekf7apsf6vtg84ue5zcq2k9q3xv5yth3q50fu4czdm8sn8q4de3m5k76g2vwwyjsf50hqfxgmwxqxu0rsy22ktw',
+    payable: true,
+  },
+  {
+    address:
+      'u1ay3aawlldjrmxqnjf5medr5ma6p3acnet464ht8lmwplq5cd3ugytcmlf96rrmtgwldc75x94qn4n8pgen36y8tywlq6yjk7lkf3fa8wzjrav8z2xpxqnrnmjxh8tmz6jhfh425t7f3vy6p4pd3zmqayq49efl2c4xydc0gszg660q9p',
+    payable: true,
+  },
+  {
+    address:
+      'u19a4vmx7ysmtavmnaz4d2dgl9pyshexw35rl5ezg5dkkxktg08p42lng7kf9hqtn2fhr63qzyhe8gtnvgtfl9yvne46x6zfzwgedx7c0chnrxty0k5r5qqph8k02zs8e3keul9vj8myju7rvqgjaysa9kt0fucxpzuky6kf0pjgy0a6hx',
+    payable: true,
+  },
+  {
+    address:
+      'u13p2teem3xlvy4kwlke24hng5el2z6mn4ftj8xarwn8fy7dqt0flgcfpaxe6sk5cwawwh4tynzu7z2uschaf8tfa3tp2xgt8g4kx5lahhglcjm26jnvw7am6ld33708g0kv35pq83eg6gj82a0aau80enrhywpgr4v4m4vve7tg8vd4hz',
+    payable: true,
+  },
+  {
+    address:
+      'u1snf9yr883aj2hm8pksp9aymnqdwzy42rpzuffevj35hhxeckays5pcpeq7vy2mtgzlcuc4mnh9443qnuyje0yx6h59angywka4v2ap6kchh2j96ezf9w0c0auyz3wwts2lx5gmk2sk9',
+    payable: true,
+  },
+  {
+    address:
+      'u1szwcx2zdxalyp7cfqwrptv95rnpyajejs6jmwacz4cgm2g3vzdxl5perhpg3nyhnuplvptdr4g63gupdfj5zal9v35s3e6adqsckv68hyrclan3gxaj6mz8aejzsnhqjyn32jcpnpra',
+    payable: true,
+  },
+  {
+    address:
+      'u1glq6lzrxc7n7r4c922qht20zmpxyl0asfuldrjcaddagfspxpc3040fdfwdf5crw4j6j6wkx4r038s0w24w7enpyfmmdfu9t9p2amxazgvasms8l03l3j5yhrrfqy6xzue5uggef4p8',
+    payable: true,
+  },
+  {
+    address:
+      'u1tqhg04ppjt6vlf2uvkygt07sqzgpclxdpn7j7ydkcr0e8ym68wn592z7uqudktrwn4u3q57flp8hw3d0wd9t0rm0e6m8eys27evfawh6zhha6eulzj86uz89swu7gtk0vcknd3dauhc96twhx20xxsp93dxahqlt7z5p04ldgy2y2lp0',
+    payable: true,
+  },
+  {
+    address:
+      'u1zm98xj3ncc79sx8jxhcscptxav0p4wam8mlkf4lp69rhramz7v6fsndwxcd4qtmzkefwcwn5rgd8uztvdrvfqv32jk3xx6wlt7gae9fhs7xh48d3kn9fe92xtcff8hu0zgegmgr95qtxayjylfdct96eg2f2r06drf6sj800mcsns3n0',
+    payable: true,
+  },
+  {
+    address:
+      'u1hfgf2s4pghqteculnmq2rcnvyesml74zqfp5yfhxhwewx62q75qhgmwreg5qht7c5vu3fxefunjrarrfhmcuw2z4ndx0qx7u74gkw2n7v0ypvd4mxgzlenvs7lkurdj09zuhz6pmtuzs4m42sx92axuuru4dmgu46a920x5kuye6gxvs',
+    payable: true,
+  },
+  {
+    address:
+      'u17cfcut587e3kszg8vud0z5a8lj9gyypyvtt5xn4hfc4p3kv4e0jfr2pzzxhywlkhsjldtmkvupwr7mkjvruz8gnxk7a64x777p4l3u7vpm6zsdsx88ef90x5q5sqx57fq8vtj5vk3hx',
+    payable: true,
+  },
+  {
+    address:
+      'u1z6qgxh0wyw0ptgwwgsr5uv05n3xm3z8yrdr06k7q6fj9ypyjcj2hxwfmktv4a7ejaqphcgkddhsvrs93skzl3frm8e48at6huayg7k67e3c50ykpdnhva2jfh5dfcvy6nvttqwgz5a7',
+    payable: true,
+  },
+  {
+    address:
+      'u1g6jcyfwqd9yx8pdg4yvf0nsr5j7k5gmx83shh8v0v3w256umheen026x66f4608w2vydyasphgp80j9avq9h56dx73gg2559l5lj707v4458a0ucyhfxcjcccfx9z9upmcf3c6hg9k8',
+    payable: true,
+  },
+  {
+    address:
+      'u1en8ysypun4gdkdnu8zqqg6k73ankr9ffwfzg08wtzg9z939w0wupewemfrc8a630e8gc4uqucym0l4v44fszy3et4veyypt3jsyp0whfpfsn2lw30kj8nepe6wvvasf00wklh85u9v8glqndupmamk9z2ja9sanf70pp4yxvkt3dmyzxa0kkhv2c9pxmkghrxqk0590azvya3nzrtevj449nu3laskrhf7c7nj9cyw7ty38mccg4znrr876guu6pzndx7ngwzhmlsn8d89saf5araaacrhr9958xr6z23mj4qtzzn98whdpu8u7n8fhf5d2vypljda62q73du44sf0e0kxmq3gvgkta0qqgq9w6r403gc5jz2any02etmwlttkv84hgh95czhdf2jugk3u36ke0kchcthg240',
+    payable: false,
+  },
+  {
+    address:
+      'u1a7gz63aey4tnj4klwauth00vnkmltwafwzk9nld2ys7yz3yjzjcdp47crc37zc4g9aq4athg9zh8r792e44kd6g2f4drhsl5ph4ja8pe4gcc9yjyf3rn7pej808hcy6xh0x6y8khmzljehjlwqq4h2czp35vu3l7aa7rpw5vcng9gswwlaqn5ptes592wejx7f49rxsvmzeqjekjtyfevehanvyksa8gtkpk75yrqnam26hzuxrtm6agaluy4hv0ha4sg6h22394m0x5th6r8uj7svzlklaja852vv9ud5gznu2sqyrsqveqjmfk9rcs59sprjj8nrt2nke862xlhvjq9y9zswen27eqj5slg52q2zch59uzwaeat8jw6z6092uu8yqqnnj7h0yguhypgd8y2wu9ftgg38ym3',
+    payable: false,
+  },
+  {
+    address:
+      'u1ln90fvpdtyjapnsqpa2xjsarmhu3k2qvdr6uc6upurnuvzh382jzmfyw40yu8avd2lj7arvq57n0qmryy0flp7tm0fw05h366587mzzwwrls85da6l2sr7tuazmv5s02avxaxrl4j7pau0u9xyp470y9hkca5m9g4735208w6957p82lxajzq4l2pqkam86y6jfx8cd8ecw2e05qnh0qq95dr09sgz9hqmflzac7hsxj47yvjd69ej06ewdg97wsu2x9wg3ahfh6s4nvk65elwcu5wl092ta38028p4lc2d6l7ea63s6uh4ek0ry9lg50acxuw2sdv02jh90tzh783d59gneu8ue3wqefjmtndyquwq9kkxaedhtqh2yyjew93ua38vp8uchug0q7kg7qvp4l65t9yqaz2w2p',
+    payable: false,
+  },
+  {
+    address:
+      'u1sem2gcey0emntrvxyjv8hyhq0w5fr4sxaj3cppgrfqgg6laydh8m78gy2cw2p54zzak3alnnsx4xjuhazpkrfcd90wl0c7ldj6y095hh5j6j2evry9vg5jqp4dyqpwqeryu7pes4sxyyyqwn6egs5daxk4473v9xpgzrwv5n0tvs93nlj4xpphq4vs2w8um9ph7zkte08t7fa509mnrt9apuhr22xq34mp2svjnq6rvfn0hg6lkehxtlj39vgjxjlkjfhx8rw2f02ckq8k5szcxsnhkgr2cqlmf2udl2gqdqr5t6',
+    payable: false,
+  },
+  {
+    address:
+      'u10j2s9sy4dmuakf57z58jc5t8yuswega82jpd2hk3q62l6fsphwyjxvmvfwy8skvvvea6dnkl8l9zpjf3m27qsav9y9nlj59hagmjf5xh0xxyqr8lymnmtjn6gzgrn04dr5s0k9k9wuxc2udzjh4llv47zm6jn6ff0j65s54h3m6p0n9ajswrqzpvy8eh4d5pvypyc6rp5m07uwmjp4sr0upca5hl7gr4pxg45m7vlnx5r7va4n6mfyr98twvjrhcyalwhddelnnjrkhcj0wcp5eyas2c2kcadrxyzw28vvv47q74',
+    payable: false,
+  },
+  {
+    address:
+      'u1mtnedjgkz5ln6zzs7nrcyt8mertjundexqdxx52n2x4ww3v52s0akf3qy6sqlze3nexcjsxtcajglxcdwg47dsrrva6g5t4nf8u3sjchhkmsqghelysrn0cl52c2m8uuv3nyfdv258jjqnvd4lgqtugc8aqvpmt05c49qv2yqlhxvnq9phdamm4xv89cc7tzvzgmwltxxdsvme44dgzt8prkcwcsma8cdr76m8n0xwj02tpr9086a237xakkdf8fumsj8u4r6qlf0d59x0mw83ar36vrcr94zsherapa0566vd22',
+    payable: false,
+  },
+  {
+    address:
+      'u1n9znrl4zyuvds24rcapzglzapqdlax4r8rgkvek0y0xlzfjfvn7zexelrafkchea24w030cr9jqsel7t8lvveaq7m7w4z0khmrlzc6748w9ldlccy02scd5xngtcv2yy4ctnyu9zn5m',
+    payable: true,
+  },
+  {
+    address:
+      'u19f2knszheph2dt8lrnwqeeq9krnw39pgz8syqv028ghtg7kjz6xvu23suv5hmdmj7e6fjuu6060y34fdw8ccjlp8gsqp0usyhrgw3reqfveet7hh2pqcjafysqqv2l3felj7sl7a7ym',
+    payable: true,
+  },
+  {
+    address:
+      'u160suxvjkgt22zcp7f9xw5f0axdu7rxdt5ktyexpn4cq70w4at2f74390mns7uksfenrdmcjjzqalyfky6tq05jv8mnamrkyxn9dcxe35z4x6m35cczmjcj55g0fc6a2thz03sjfywxa',
+    payable: true,
+  },
+  {
+    address:
+      'u1ddnjsdcpm36r6aq79n3s68shjweksnmwtdltrh046s8m6xcws9ygyawalxx8n6hg6vegk0wh8zjnafxgh6msppjsljvyt0ynece3lvm0',
+    payable: true,
+  },
+  {
+    address:
+      'u1nztelxna9h7w0vtpd2xjhxt4lpu8s9cmdl8n8vcr7actf2ny45nd07cy8cyuhuvw3axcp545y0ktq9cezuzx84jyhex8dk4tdvwhu4dl',
+    payable: true,
+  },
+  {
+    address:
+      'u1trxzh330wl8wkh92uwv508z0qfx270ruuar8fxeng7arry5d73q9ve6gfud36s9nc4qj3uvn082l9srrfayjhnf20mmunywtvqzgc90c',
+    payable: true,
+  },
+  {
+    address:
+      'u1xdrenc94696j8clxa2xnkdg8xd5t3y8s24urctyxu87vggv0u46qr4lkpnh7gqqdev9wwugt6xkv8c8du8ufhfl8nfjnzusf6cw20wpm85hlshmnmj2lkyhka9rua7qw7kr0xeajk7y2rlsuwl6z6l5l3wq3v6rrqt9e8zy7sc7pww45jznrj4xy6h9rp4kjy5xtl5upr30u4cyk58kv3t80k3p8w97k3e345h7avmjylxakx6sgyk5ss8th5kqay50ewav62eeep7tghzejaflsdstpwz55haex398jqpq27007me2',
+    payable: false,
+  },
+  {
+    address:
+      'u1y647tzm2ms4stj8skfswfljmvatmhwqzjzl2uq5v3a78ys2mls2g9thdap4yfmr9tw6y5h9gnehzhpddyl43enmhd6xv2udcttqmas35l62jt2yar33jwr5eulchzxg3d8upf2raqcx3jup8s3dep6an5n5xh9ngdjfp4hjv8fwfhh34kvglsug57zf0duypq6ugmysw0mnhdg5fz9sndputdc7pdssg6k3ks76wrrnuu5najqxj8xchp5xv5ahfh3f2szrfl5cm6mslq2f69ja9r54plen209xwpdpwsvm6zep4gwl',
+    payable: false,
+  },
+  {
+    address:
+      'u1m5jvynaxyrtk27mt23q0j4r8uf5dzzhlwf6qd4s7pfdclqnmgkaf82kqrch0p44kd97f9pmwnk6q3rnjnzvlwv2ll289ahzlee4zcnual03ntelg2q2wxlqc6ueav935j4j2rzv2gxcdh6lk67quzxnxt5ay9xh0qjc9575dptfs9luhhr0m9wms2taq2vnrryjdj3ht5cktwathcerl9kw25y89f3hffyr65rnfw0jk2ka7703m8wym0c04u6r0xgagpn7xzfaxttrwgftmztzln6y2qcdglk3u28dgrswywqne28g',
+    payable: false,
+  },
+  {
+    address:
+      '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',
+    payable: false,
+  },
+  {
+    address:
+      'u1adph5ua2pv8ghr7utshst0fm0ad7tj32y09t2nhxn2ccwm6hengck3w2vy34tvhqay7rlw8vcfh63f85lh7lz63l0c5vja49tu8vcxvx30re085n8jt5hcqh4g4ec77czl4c8nspqps2ac2g5kxhl4j5g6mz3vsvxrg74e8p9s8hhqu8u3gldhxvrxg2htykqc7ceh930f3edxsg49nctv2e36cne6qpkvxzfymh2el2eguw6kg7zvdu620rgk4cwyvt9hz7zpjk9wskjdpk6p3cpyx3yuf5lk46nx2fyqjca3vtz8d9df3tpmg74d90uv7pp09apfa5ep374clznmh2ne5suxtzk22cp7mvu9gtswpvx9wfst63s73yjwqu9cjenwntdsep0uqz2hgnh4xpq0rlllwgv8z70ke6z5zkwnjmlrzt6nsvhac4zz245rp3rkj9lmj8tvpfmd0zawy08dv3hqxxf8cr06x90amtgkh2ura0yyfwucu',
+    payable: false,
+  },
+  {
+    address:
+      'u12acx92vw49jek4lwwnjtzm0cssn2wxfneu7ryj4amd8kvnhahdrq0htsnrwhqvl92yg92yut5jvgygk0rqfs4lgthtycsewc4t57jyjn9p2g6ffxek9rdg48xe5kr37hxxh86zxh2ef0u2lu22n25xaf3a45as6mtxxlqe37r75mndzu9z2fe4h77m35c5mrzf4uqru3fjs39ednvw9ay8nf9r8g9jx8rgj50mj098exdyq803hmqsek3dwlnz4g5whc88mkvvjnfmjldjs9hm8rx89ctn5wxcc2e05rcz7m955zc7trfm07gr7ankf96jxwwfcqppmdefj8gc6508gep8ndrml34rdpk9tpvwzgdcv7lk2d70uh5jqacrpk6zsety33qcc554r3cls4ajktg03d9fye6exk8gnve562yadzsfmfh9d7v6ctl5ufm9ewpr6se25c47huk4fh2hakkwerkdd2yy3093snsgree5lt6smejfvse8v',
+    payable: false,
+  },
+  {
+    address:
+      'u1uehkuaq6rpfgt4ed5zpvhczg9apgpmyk5eq9qg23j8w7jxkhdnqzacte6gu8zgzfzgxy48ryzus3wnkhfxrxmlhs34xde3f34uxcnv3y6dsgj288vu56xs9f6ghvqsgkhuwtz4kkfxj8pa27v5p3ttlst340zvwx9nj6s0zw8p3wwk3zh37dwc7znqz52gj2fpaapzxzyagah0aeyxwa9fxxvyyj6w989v96ymsgf7s8s6ej9346p60fcjzzynvf9rmxevumdvt8l9mvhdfz4u5j4h7e0zjr2sde7fu7z9s02447qg6qzllm22egnx6ej6qczkkk2ygvpy08un9ggp853sddp6vskrlar6sygxec5f6c2t2eu9zmc728esy4sj9z853gxuplr6hw7lpcwzk20d85vuflnhlfv8nr3020r0v9z83ryudsyjv66rttxq2cscqlrdxakrmpjptzcf',
+    payable: false,
+  },
+  {
+    address:
+      'u1m76hh3wch9vwctg92h0jjt8zu6dry4zl97q9q94huutng5sxyhlzgfj64jqnvla2vqrqe0ndt67td2kejv6zlcw9zeurexxs67l7y67p7mww2j2uvfsp6uynct2apcr0m9xrmswtktmgs3x2glvndrqazy0gyrp30j328h4m5gkju9rl3pfrtjn9tm8v0rzr6t8gkklqfxgwk976dvv4kh7hl5utp9gjryu8wwu80h733ss5cjwpeewdgd3l8h46c0c7hxz4c6daws3vurq2fj9h0hpjnycup9tu8nfahvqjxewyhyuzynnjxa7jrvw2ekdytqs7sn02gqx4vxtkjzfrcy67lkmr6p5kalj0g8apazeyzqw3ywppy9482wj8k4tm06573nr3h78ecq9n260g7c0hm5jm3ffa4g2vk0edpdsnemksdegxgt9s7h8v8pjmcp23rnahmzf8pxdtdt',
+    payable: false,
+  },
+  {
+    address:
+      'u1c2tpmmdl49pdcfntc2e2gjaxmj2a0ackydlj9aeuqlet4erjdn2edwvtx6vd8nrkxjnvgckn4j3nx48p2gep5x23akrl2cv7u2un4vmjed9hav39taqgzyp602m3tpcv3uzdsjdyl8wxrjycx5aus8ypq2xja8yw0cf045n0zvwt3ajtgs2xyzjl6cq2245avkm26qjv72ta65h04etlp4ntdq87eu9efjx5v6gjsfvwrdt99m4lpu9j52t0h8yvpnzukuzdt89e3pg9cmderzh7tnahmw0rfyc37aqmd6dh24fnxmxagsj4mtz8jv3c3ch20xu4k6whwfsaf2sra4ktgdej9p6kqz05ae3vl3f93xsfx05xpaf884h56epcetx627jttgx2499vc0uzxl83hcdt92z4hy5la40ervrpha4kn3kxxwrngdj76u6mrfcmt4737czn08vd60k5gj',
+    payable: false,
+  },
+  {
+    address:
+      'u1dqavtnjvu42hlsjw6sc2mxajqlyt03zg8l4luykz9fnchunq74nqxhfp58h5n5xfpyqhheax8thta8lfkjgp8wqwsavc0g4mgu4du02c',
+    payable: true,
+  },
+  {
+    address:
+      'u1q8g29qhrktunc24lud3fgk007u7ya8q5g8vy9awadxtl7wu5vjllr4mmdfwk0zdh8zqxgl93sthzumeanzzkdqmqdft6ryhwtvqyqt3e',
+    payable: true,
+  },
+  {
+    address:
+      'u13j3q8q8f9hx2nx0w9l52dqksy4png7fgm0lqjh8ahn9enyvz5z9xnwzdcdjmpf756s2y88rnyr9px4f4k9w03sl6fr4vwsqcvg8ggfjx',
+    payable: true,
+  },
+  {
+    address:
+      'u1ukslldhknrzmvpdmn03u03edgfy976w3muurfs9asvh3n9uh9h6sgle6m7yjgf3wafxtvke08u735v4nd3kjqnyulw7cvxh6ke357knyjudgqtes6kcw7y28e6kewr03pjah5mh26na',
+    payable: true,
+  },
+  {
+    address:
+      'u1a0dnfvgdp4khm5yk79ltkkvp8jjmjykjy38cdue8ktl8askwenl4lzfyu0p7end0guyu6up57wylzns0tpr99wz5z8edh5u0m4yzuusysr3d2xczwkp82atq3vfw45u2yvtau852lnw',
+    payable: true,
+  },
+  {
+    address:
+      'u1a84vn0qes8q3jhk7zxs2whd2p922far8kztqdapergs5ej8rarn53v5ddnd6t7e3l5efhaefrhkptatnzq565nrpvf7kn2787gdvervmk08azp4qgehaew2zplkxkkyu36l3v7drg2v',
+    payable: true,
+  },
+  {
+    address:
+      'u187vrwl4ampyxd5m6aj38n4ndkmj8v6gs97hkt23aps3sn5k89a0gk2smluexgdprcrtm56ezc5c7tjwlrnnl79tjtrxmqd42c5mpyz7g',
+    payable: false,
+  },
+  {
+    address:
+      'u1xd83nhheggwe78x3lvcygdl8cmwz3gfxnr02sytkxvfpwdep9dzl7vte48zhkx39s705yqp20rw4l835fhg3ylkde44l7glt3cyps5wk',
+    payable: false,
+  },
+  {
+    address:
+      'u1w7x9ttwvk30grems6ae3rhgs6xytrrueaklyc5t509fpux7043fzla70jehhxyn4mg9d3ym095s3wghl9trvvdmu56yn74ajqy38ufjg',
+    payable: false,
+  },
+  {
+    address:
+      'u1smpx6drvevct3dyrer7esjlct99lf4nxdeltdetyxjdrmtqag7q7mkrd8rxlvj9e5vy0qy24fhvvvrj7agfdgxapefxe72xl8vuu9ds5yfq0p86r3y0jw4suurzjz5s6lzrxkfft4am',
+    payable: true,
+  },
+  {
+    address:
+      'u1ymxkv9nks7tuzjt265fg8vctdq5nxqw4l0q2xj2ya5dkt660rrzkg032v5duhgeqae6cnh9tzxry4dspv8yvtq5lem9gujysaz64034mavd8p0ejqhnvp2jg34nt24y2c2whclxxk94',
+    payable: true,
+  },
+  {
+    address:
+      'u14j8rtl62a70skh0nhzv7tasxsa69axm0vlac37ye3mcgfpjk6k9ury7hlmet0grhvhedtfj27xmsygp06pcm932f8sc33u5uwps57d89667kyhwmj8pucp5r8cel2lhuaxmx5ftm2nt',
+    payable: true,
+  },
+  {
+    address:
+      'u1xjkw3lwwf9crx8cz050gdwfejufzhcusc37ged99w8fyj7tyx3e7hgmauyuv538dak2sepq6wjv4tyyjnhcef02dr682y5dsuzuftsx83lrvfc6dxd0kk260m4p3c9ka96vf3z9u6axvsj47mfd6kszy39e5gma28yg88yp92kxjt8ah0x329j4gxjdfyn0n2wp3urwrxxz6z0ynx82',
+    payable: true,
+  },
+  {
+    address:
+      'u1p4c4u3uz2vtkedv78d4phjav86exankz0x9wmrmz8q4mxqaf43gwd0qt486jk5jvpvyccc6lyy2vaq3ht8ngnw4vusryxd9erhhl2uy5x6x4huyfdymwxj7dkyyeut8ld36kxwu3v5wjg7jwp9kr8ul7u3xdakfunvmwq0rkv6y4k0ngm2n24x763uurfmrr685welsefyys2xwp8ug',
+    payable: true,
+  },
+  {
+    address:
+      'u1ap7zakdnuefrgdglr334cw62hnqjkhr65t7tketyym0amkhdvyedpucuyxwu9z2te5vp0jf75jgsm36d7r09h6z3qe5rkgd8y28er6fz8z5rckspevxnx4y9wfk49njpcujh5gle7mfan90m9tt9a2gltyh8hx27cwt7h6u8ndmzhtk8qrq8hjytnakjqm0n658llh4z0277cyl2rcu',
+    payable: true,
+  },
+  {
+    address:
+      'u1udmzarqn6y9026whk083lm5vs8pv282egeln6xg0n2a3w4klkpn6208h68ntuus7gp54d937u4f724v2xgdx6qeu74j45vxfn822xty2yyx6u0ecakj8r9uu3r2jqafj64w7updkhtq',
+    payable: true,
+  },
+  {
+    address:
+      'u1fyvdgdehrx3gvjx5f2ez2lkcm0lcrfxg8hksdmg3g8zujfz8xk2kyhu4dafs99y96sq2t5c3d3zsxhhnlfmj6trmttg5awtwczz8g8xjr7u30hxc4nkyfyefyl4xt3dxdjevsnrkqdg',
+    payable: true,
+  },
+  {
+    address:
+      'u1kfzux4hf9favh8jmssqa2h04k87advldqz5ze7a8t4un3nkegklhz3ewzk6lmqg0uy7matdway9vn2q8q9rxp0fjwuewpcjtwrwavxjdsfxdvsk5nkx4q35atp0tfepfdsapqkk4en5',
+    payable: true,
+  },
+  {
+    address:
+      'u1hrwrtyl3m8m2c6vkhu8wng43j5yvwweg37n2qstsqwc9dfw4vhs69m09064522758p44pfz42gu6hydjxua0wt0ge907sgrxkc9mft4gyfjevkhsyl4d8lnzgyd90arhx4t6v20zlfz',
+    payable: false,
+  },
+  {
+    address:
+      'u1rf4n5f682jspygln8r5pjwh6fmta7xz6n9x868f5wgc9prxsqkrh8jkpmn7wfnag56ml7czw68dv96299ft6s98p05u4jvdx3elyr83jqnzr603vw8yarptpg5pj73zlea0sksuje3r',
+    payable: false,
+  },
+  {
+    address:
+      'u1l6exm3zmfsr74sqvlwgc0zf7mydwf6z5r79amka84kfwzwef3wxs0yupl2lwhws85vdmqet3rtz795gpnm4h0jjfv4hanwqta0ezlxqe4p578a4aq09s93xhhtf3xhtrlh575qrsf5g',
+    payable: false,
+  },
+]
+
+/** `[raw, jumbled]` hex pairs up to 193 bytes; the longer rows add no other branch. */
+export const f4JumbleVectors: [string, string][] = [
+  [
+    '5d7a8f739a2d9e945b0ce152a8049e294c4d6e66b164939daffa2ef6ee6921481cdd86b3cc4318d9614fc820905d042b',
+    '0304d029141b995da5387c125970673504d6c764d91ea6c082123770c7139ccd88ee27368cd0c0921a0444c8e5858d22',
+  ],
+  [
+    'b1ef9ca3f24988c7b3534201cfb1cd8dbf69b8250c18ef41294ca97993db546c1fe01f7e9c8e36d6a5e29d4e30a73594bf5098421c69378af1e40f64e125946f',
+    '5271fa3321f3adbcfb075196883d542b438ec6339176537daf859841fe6a56222bff76d1662b5509a9e1079e446eeedd2e683c31aae3ee1851d7954328526be1',
+  ],
+  [
+    '62c2fa7b2fecbcb64b6968912a6381ce3dc166d56a1d62f5a8d7551db5fd9313e8c7203d996af7d477083756d59af80d06a745f44ab023752cb5b406ed8985e18130ab33362697b0e4e4c763ccb8f676495c222f7fba1e31defa3d5a57efc2e1e9b01a035587d5fb1a38e01d94903d3c3e0ad3360c1d3710acd20b183e31d49f',
+    '498cf1b1ba6f4577effe64151d67469adc30acc325e326207e7d78487085b4162669f82f02f9774c0cc26ae6e1a76f1e266c6a9a8a2f4ffe8d2d676b1ed71cc47195a3f19208998f7d8cdfc0b74d2a96364d733a62b4273c77d9828aa1fa061588a7c4c88dd3d3dde02239557acfaad35c55854f4541e1a1b3bc8c17076e7316',
+  ],
+  [
+    '25c9a138f49b1a537edcf04be34a9851a7af9db6990ed83dd64af3597c04323ea51b0052ad8084a8b9da948d320dadd64f5431e61ddf658d24ae67c22c8d1309131fc00fe7f235734276d38d47f1e191e00c7a1d48af046827591e9733a97fa6b679f3dc601d008285edcbdae69ce8fc1be4aac00ff2711ebd931de518856878f7',
+    '7508a3a146714f229db91b543e240633ed57853f6451c9db6d64c6e86af1b88b28704f608582c53c51ce7d5b8548827a971d2b98d41b7f6258655902440cd66ee11e84dbfac7d2a43696fd0468810a3d9637c3fa58e7d2d341ef250fa09b9fb71a78a41d389370138a55ea58fcde779d714a04e0d30e61dc2d8be0da61cd684509',
+  ],
+  [
+    '3476f21a482ec9378365c8f7393c94e2885315eb4671098b79535e790fe53e29fef2b3766697ac32b4f473f468a008e72389fc03880d780cb07fcfaabe3f1a84b27db59a4a153d882d2b2103596555ed9494c6ac893c49723833ec8926c1039586a7afcf4a0d9c731e985d99589c8bb838e8aaf745533ed9e8ae3a1cd074a51a20da8aba18d1dbebbc862ded42435e92476930d069896cff30eb414f727b89e001afa2fb8dc3436d75a4a6f26572504b192232ecb9f0c02411e52596bc5e9045',
+    '5139912fe8b95492c12731995a0f4478dbeb81ec36653a21bc80d673f3c6a0feef70b6c566f9d34bb726c098648382d105afb19b2b8486b73cbd47a17a0d2d1fd593b14bb9826c5d114b850c6f0cf3083a6f61e38e42713a37ef7997ebd2b376c8a410d797b3932e5a6e39e726b2894ce79604b4ae3c00acaea3be2c1dfe697fa644755102cf9ad78794d0594585494fe38ab56fa6ef3271a68a33481015adf3944c115311421a7dc3ce73ef2abf47e18a6aca7f9dd25a85ce8dbd6f1ad89c8d',
+  ],
+  [
+    '7e745939ffedbd12863ce71a02af117d417adb3d15cc54dcb1fce467500c6b8fb86b12b56da9c382857deecc40a98d5f2935395ee4762dd21afdbb5d47fa9a6dd984d567db2857b927b7fae2db587105415d4642789d38f50b8dbcc129cab3d17d19f3355bcf73cecb8cb8a5da01307152f13936a270572670dc82d39026c6cb4cd4b0f7f5aa2a4f5a5341ec5dd715406f2fdd2afa733f5f641c8c21862a1bafce2609d9eecfa158cfb5cd79f88008e315dc7d8388e76c1782fd2795d18a763624',
+    '1a52585e652da6ea46994954905cb79f55fca58171a4d7f773a57d23ed9ddec0c745ef0f4588fa7b2b68d69cdd25e5eb0e08c20523a3957171f1730ab0636faee75da2dc9e89562f0653d4e9422179286ae8305f01371f47ab16eed692c3895ce2fd655e4b19651c35d83c81894f687055b581114440646508e39a49b0d5a99004560af7367cc2738344d4e797a995ed66df72228e3d3746674337104700144c73b6db27d238c9e1770662feb0957d5028b5086f3839aacf275022dd7e7e983b6d',
+  ],
+]
diff --git a/packages/sdk-provider-zcash/src/utils/zcashAddress.ts b/packages/sdk-provider-zcash/src/utils/zcashAddress.ts
index 751e854cc..509bc996e 100644
--- a/packages/sdk-provider-zcash/src/utils/zcashAddress.ts
+++ b/packages/sdk-provider-zcash/src/utils/zcashAddress.ts
@@ -1,14 +1,10 @@
 import { sha256 } from '@noble/hashes/sha2'
 import { createBase58check } from '@scure/base'
+import { isOrchardUnifiedAddress } from './unifiedAddress.js'
 
 const base58check = createBase58check(sha256)
 
-/**
- * Whether `address` is a mainnet transparent Zcash address (`t1` P2PKH or `t3`
- * P2SH) with a valid checksum. The API handles transparent receivers only, so
- * TEX, Sapling and unified addresses, and testnet forms, return `false`.
- */
-export const isZcashAddress = (address: string): boolean => {
+const isTransparentZcashAddress = (address: string): boolean => {
   let payload: Uint8Array
   try {
     payload = base58check.decode(address)
@@ -22,3 +18,12 @@ export const isZcashAddress = (address: string): boolean => {
     (payload[1] === 0xb8 || payload[1] === 0xbd)
   )
 }
+
+/**
+ * Whether `address` is a mainnet Zcash address the API pays to: a transparent
+ * `t1` (P2PKH) or `t3` (P2SH) address with a valid checksum, or a unified `u1`
+ * address with an Orchard receiver. Sapling, TEX and testnet addresses, and a
+ * unified address without an Orchard receiver, return `false`.
+ */
+export const isZcashAddress = (address: string): boolean =>
+  isTransparentZcashAddress(address) || isOrchardUnifiedAddress(address)
diff --git a/packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts b/packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts
index 3f88ec269..ac3d97cfa 100644
--- a/packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts
+++ b/packages/sdk-provider-zcash/src/utils/zcashAddress.unit.spec.ts
@@ -2,14 +2,17 @@ import { describe, expect, it } from 'vitest'
 import { isZcashAddress } from './zcashAddress.js'
 
 // Sources: ZIP 320 (t1 and its TEX form), ZIP 214 (t3), zcash-test-vectors
-// unified_address.json (u1, and the Sapling raw address of row 0 encoded as zs1).
+// unified_address.json (row 0: transparent and Sapling receivers, and that
+// Sapling raw address encoded as zs1), and a Zashi address with an Orchard receiver.
 const t1 = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yC'
 const t3 = 't3LmX1cxWPPPqL4TZHx42HU3U5ghbFjRiif'
 const tex = 'tex1s2rt77ggv6q989lr49rkgzmh5slsksa9khdgte'
 const sapling =
   'zs1mrhc9y7jdh5r9ece8u5khgvj9kg0zgkxzdduyv0whkg7lkcrkx5xqem3e48avjq9wn2rukydkwn'
-const unified =
+const unifiedWithoutOrchard =
   'u1l8xunezsvhq8fgzfl7404m450nwnd76zshscn6nfys7vyz2ywyh4cc5daaq0c7q2su5lqfh23sp7fkf3kt27ve5948mzpfdvckzaect2jtte308mkwlycj2u0eac077wu70vqcetkxf'
+const unifiedWithOrchard =
+  'u1k9eh52jx5q4y8lw6x208lsep4t6yzwk7mdwz9e6239qywjkqzdcd3al3d64zwnqx296p3klxnash5w2e0elg39qrydxx0s0qz5m2gnt0'
 // The t1 above with its last character changed: the checksum no longer matches.
 const t1WithBadChecksum = 't1VmmGiyjVNeCjxDZzg7vZmd99WyzVby9yD'
 // Testnet forms of the same hash: version 0x1D25 and HRP `textest`.
@@ -18,16 +21,17 @@ const testnetTex = 'textest1s2rt77ggv6q989lr49rkgzmh5slsksa90ej7wz'
 
 describe('isZcashAddress', () => {
   it.each([
-    ['p2pkh', t1],
-    ['p2sh', t3],
-  ])('accepts a %s address', (_, address) => {
+    ['a p2pkh', t1],
+    ['a p2sh', t3],
+    ['an Orchard unified', unifiedWithOrchard],
+  ])('accepts %s address', (_, address) => {
     expect(isZcashAddress(address)).toBe(true)
   })
 
   it.each([
     ['a TEX address', tex],
     ['a Sapling address', sapling],
-    ['a unified address', unified],
+    ['a unified address without an Orchard receiver', unifiedWithoutOrchard],
     ['a corrupted checksum', t1WithBadChecksum],
     ['a testnet transparent address', testnetTransparent],
     ['a testnet TEX address', testnetTex],