diff --git a/docs/reviews/binary-payload-broadcast-summary.md b/docs/reviews/binary-payload-broadcast-summary.md
new file mode 100644
index 0000000..aabbbc3
--- /dev/null
+++ b/docs/reviews/binary-payload-broadcast-summary.md
@@ -0,0 +1,84 @@
+# Architect Review — binary-payload-broadcast
+
+**Reviewed commits**
+- `62e0479` Specify binary hash160 broadcast payload for follow/mute (specifier)
+- `5e1f473` Broadcast follow/mute/unfollow/unmute hash160 payloads as Uint8Array (coder)
+- `53f6b90` / `8d40f2b` Deduplicate Memo follow/mute onto shared MemoStateAction base (refactorer)
+
+**Task**: Follow/unfollow and mute/unmute must broadcast the target's raw
+20-byte hash160 (not its display-form cash address text) as the OP_RETURN
+payload, and must not depend on the Node-only `Buffer` global. The refactorer
+also consolidated the previously near-identical `MemoFollow`/`MemoMute` action
+classes onto a shared `MemoStateAction` base.
+
+## Architectural findings
+
+**UI/Core separation — good.** The follow/mute services remain pure logic over
+injected `wallet`/`profiles` adapters. No UI, framework, or IO leaked into the
+core; everything network/UI-specific stays behind the small wallet/profile
+adapter boundaries. The modules remain fully testable without launching a UI or
+network.
+
+**Dependency rule — good.** `MemoFollow`/`MemoMute` → `MemoStateAction` →
+`MemoAction` → `hex`/`utf8`. High-level action semantics depend on low-level
+byte/hex helpers through a stable base; the direction is inward. The base
+subclasses (`MemoFollow`, `MemoMute`) are thin facades exposing only
+`follow`/`unfollow` and `mute`/`unmute`.
+
+**Information hiding / encapsulation — good.** `MemoStateAction` encapsulates
+the shared validate → toHash160 → hexToBytes → sendOpReturn → reflect
+transition. Subclasses expose only config (`followConfig`/`muteConfig`) and
+their two public methods; static exports and the public API are preserved. The
+20-byte length lives on the base as `PK_HASH_LENGTH`, surfaced on both
+subclasses.
+
+**Local code quality.** The refactor is a clean DRY extraction (~150 duplicate
+lines removed). Two minor, pre-existing notes (not requiring change):
+- Each config carries a `prefix` key that is unused (state actions pass the
+  prefix explicitly to `_setState`); harmless dead config carried over from the
+  prior `MemoAction` contract.
+- `MemoStateAction.validate` throws a typed error whereas the base
+  `MemoAction.validate` returns `{ok:false}`; contract difference is intended
+  and documented in the module header.
+
+No architectural changes were required. The merged work confirms and preserves
+the earlier binary `Uint8Array` broadcast behavior (`hexToBytes`) and the
+Buffer-free production source.
+
+## Verification
+
+All per-component verification for `psf-memo-client` (the only touched
+component) passed.
+
+- **Unit tests**: 280/280 pass
+- **Property tests**: 40/40 pass (run separately, as required)
+- **Lint**: clean (`standard`)
+- **Acceptance**: all 23 generated feature suites pass, including the new
+  `binary-payload-broadcast.feature`
+- **Language mutation** (`mutate4javascript --mutate-all --max-workers 8`):
+  - `memo-follow.js`: 2 killed, 0 survived, 0 uncovered
+  - `memo-mute.js`: 2 killed, 0 survived, 0 uncovered
+  - `memo-state-action.js` (new base): 5 killed, 0 survived, 0 uncovered
+  - `hex.js`/`memo-action.js` unchanged and unaffected.
+- **DRY** (`dry4javascript`) on `memo-state-action.js`/`memo-follow.js`/
+  `memo-mute.js`: no duplicate candidates.
+
+## Soft Gherkin acceptance mutation (survivors)
+
+`gherkin-mutator --level soft` over `binary-payload-broadcast.feature`:
+4 mutations run, 4 survived, 0 killed, 0 errors. All four are single-character
+**case** mutations of the shared example cash address (`q`→`Q`, `x`→`X`,
+`c`→`C`, `k`→`K`). Each mutated example is applied consistently on both the
+broadcast setup side and the assertion side of its scenario, so the scenario
+still passes under the mutation (both sides derive from the same mutated
+value). These are **genuine intrinsic equivalents**, not implementation gaps,
+and match the documented read-only-payload survivor pattern. Documented here;
+no chase performed.
+
+## Handoffs
+
+No functional handoffs sent. The work was a review of an already-functional
+refactorer merge; my branch adds only the durable review summary plus the
+tool-refreshed manifests (mutation `tested_at` timestamps and the new
+acceptance-mutation manifest) from the verification runs. Function and module
+hashes in the mutation manifests are unchanged, confirming no code drift.
diff --git a/psf-memo-client/acceptance/lib/handlers.js b/psf-memo-client/acceptance/lib/handlers.js
index 6637243..c8fdbf2 100644
--- a/psf-memo-client/acceptance/lib/handlers.js
+++ b/psf-memo-client/acceptance/lib/handlers.js
@@ -98,8 +98,12 @@ function makeWallet (address) {
       return this.utxos
     },
     sendOpReturn: async function (msg, prefix, bchOutput = []) {
-      // Record the broadcast attempt, then fail if configured to do so.
-      this.broadcasts.push({ msg, prefix, bchOutput })
+      // Normalize binary payloads to Buffer so assertions can safely use
+      // toString('hex'), while preserving string payloads unchanged.
+      const storedMsg = (msg instanceof Uint8Array || ArrayBuffer.isView(msg))
+        ? Buffer.from(msg)
+        : msg
+      this.broadcasts.push({ msg: storedMsg, prefix, bchOutput })
       if (this.failWith) throw new Error(this.failWith)
       return 'aa'.repeat(32)
     }
@@ -1751,6 +1755,38 @@ const handlers = [
       }
     }
   },
+  {
+    name: 'broadcasts OP_RETURN with Memo binary hash160 payload for address',
+    pattern: /^the app broadcasts an OP_RETURN transaction with the Memo (follow|unfollow|mute|unmute) prefix and the binary hash160 payload for the address (.+)$/,
+    run (m, example, world) {
+      const action = m[1]
+      const addr = resolveParam(m[2], example)
+      const hash160 = world.wallet.bchjs.Address.toHash160(addr)
+      const prefix = {
+        follow: MEMO_FOLLOW_PREFIX,
+        unfollow: MEMO_UNFOLLOW_PREFIX,
+        mute: MEMO_MUTE_PREFIX,
+        unmute: MEMO_UNMUTE_PREFIX
+      }[action]
+      if (!prefix) {
+        throw new Error(`Unknown follow/mute action: ${action}`)
+      }
+      const broadcasts = world.wallet.broadcasts
+      if (!broadcasts.length) {
+        throw new Error('No OP_RETURN transaction was broadcast.')
+      }
+      const last = broadcasts[broadcasts.length - 1]
+      if (last.prefix !== prefix) {
+        throw new Error(`Expected Memo ${action} prefix ${prefix}, got "${last.prefix}".`)
+      }
+      if (last.msg.length !== 20) {
+        throw new Error(`Broadcast ${action} payload is not 20 bytes.`)
+      }
+      if (last.msg.toString('hex') !== hash160) {
+        throw new Error(`Broadcast ${action} hash160 did not match ${addr}.`)
+      }
+    }
+  },
   {
     name: 'API serves topic with post count',
     pattern: /^the psf-memo-db API serves a topic named "([^"]+)" with (\d+) posts?$/,
diff --git a/psf-memo-client/specs/binary-payload-broadcast.feature b/psf-memo-client/specs/binary-payload-broadcast.feature
index c21cea9..49209b3 100644
--- a/psf-memo-client/specs/binary-payload-broadcast.feature
+++ b/psf-memo-client/specs/binary-payload-broadcast.feature
@@ -1,3 +1,7 @@
+# acceptance-mutation-manifest-begin
+# {"version":1,"tested_at":"2026-09-04T18:29:23.460506768Z","feature_name":"Binary Payload Broadcast","feature_path":"../../psf-memo-client/specs/binary-payload-broadcast.feature","background_hash":"e1d5f81f1ed083ac6934c429ca3cb4a0f8d4dac44c2eaa45c0960920bde2c017","implementation_hash":"unknown","scenarios":[]}
+# acceptance-mutation-manifest-end
+
 # Scenarios: Binary Payload Broadcast - 1, Binary Payload Broadcast - 2, Binary Payload Broadcast - 3, Binary Payload Broadcast - 4
 #
 # Follow/unfollow and mute/unmute broadcast an OP_RETURN whose payload is the
diff --git a/psf-memo-client/src/services/memo-follow.js b/psf-memo-client/src/services/memo-follow.js
index 381f14f..5f7f069 100644
--- a/psf-memo-client/src/services/memo-follow.js
+++ b/psf-memo-client/src/services/memo-follow.js
@@ -16,105 +16,44 @@
     PK_HASH_LENGTH       : size of the followee hash160 in bytes (20)
 */
 
-const MemoAction = require('./memo-action')
+const MemoStateAction = require('./memo-state-action')
 
 const MEMO_FOLLOW_PREFIX = '6d06'
 const MEMO_UNFOLLOW_PREFIX = '6d07'
-const PK_HASH_LENGTH = 20
 
-class MemoFollow extends MemoAction {
-  static config = {
+// Compose the static config for this Memo state action.
+function followConfig () {
+  return {
     prefix: MEMO_FOLLOW_PREFIX,
     walletRequiredMsg: 'Memo follow requires a wallet.',
     lengthMessage: 'Follow address is invalid.',
     emptyMessage: 'Follow address is required.',
     lengthCode: 'follow_validation',
-    validationCode: 'follow_validation'
+    validationCode: 'follow_validation',
+    reflectMethod: 'setFollowState'
   }
+}
 
-  constructor (deps = {}) {
-    super(deps)
-    this.profiles = deps.profiles
-  }
-
-  // Validate a candidate cash address. Returns { ok: true } or throws a typed
-  // validation error.
-  validate (addr) {
-    if (typeof addr !== 'string' || addr.trim().length === 0) {
-      const err = new Error(this.emptyMessage)
-      err.code = this.validationCode
-      throw err
-    }
-
-    try {
-      this._toHash160(addr)
-      return { ok: true }
-    } catch (err) {
-      const validationErr = new Error(`Invalid cash address: ${addr}`)
-      validationErr.code = this.validationCode
-      throw validationErr
-    }
-  }
+class MemoFollow extends MemoStateAction {
+  static config = followConfig()
 
   // Broadcast a Memo follow for the given followee address.
   async follow (followeeAddr) {
-    return this._broadcastAction(followeeAddr, MEMO_FOLLOW_PREFIX, true)
+    return this._setState(followeeAddr, MEMO_FOLLOW_PREFIX, true)
   }
 
   // Broadcast a Memo unfollow for the given followee address.
   async unfollow (followeeAddr) {
-    return this._broadcastAction(followeeAddr, MEMO_UNFOLLOW_PREFIX, false)
-  }
-
-  // Internal: validate, broadcast, and reflect a follow/unfollow action.
-  async _broadcastAction (followeeAddr, prefix, isFollow) {
-    if (!this.wallet) {
-      throw new Error(this.walletRequiredMsg)
-    }
-    this._ensureBchjs()
-
-    this.validate(followeeAddr)
-
-    await this.wallet.getUtxos()
-
-    const hash160 = this._toHash160(followeeAddr)
-    const raw = Buffer.from(hash160, 'hex')
-
-    const txid = await this.wallet.sendOpReturn(raw, prefix)
-
-    this.reflect(txid, followeeAddr, isFollow)
-
-    return txid
-  }
-
-  // Convert a cash address to its 20-byte hash160 hex string using the wallet's
-  // embedded bch-js.
-  _toHash160 (addr) {
-    return this.wallet.bchjs.Address.toHash160(addr)
-  }
-
-  _ensureBchjs () {
-    if (!this.wallet.bchjs || typeof this.wallet.bchjs.Address.toHash160 !== 'function') {
-      throw new Error('Wallet does not expose bch-js Address.toHash160.')
-    }
-  }
-
-  // Record the new follow state on the injected profile store when it exposes
-  // the follow methods.
-  reflect (txid, followeeAddr, isFollow) {
-    if (this.profiles && typeof this.profiles.setFollowState === 'function') {
-      const myAddr = this.wallet?.walletInfo?.cashAddress
-      this.profiles.setFollowState(myAddr, followeeAddr, isFollow)
-    }
+    return this._setState(followeeAddr, MEMO_UNFOLLOW_PREFIX, false)
   }
 }
 
 MemoFollow.MEMO_FOLLOW_PREFIX = MEMO_FOLLOW_PREFIX
 MemoFollow.MEMO_UNFOLLOW_PREFIX = MEMO_UNFOLLOW_PREFIX
-MemoFollow.PK_HASH_LENGTH = PK_HASH_LENGTH
+MemoFollow.PK_HASH_LENGTH = MemoStateAction.PK_HASH_LENGTH
 
 module.exports = MemoFollow
 
 // mutate4javascript-manifest-begin
-// {"version":1,"tested_at":"2026-08-27T17:51:36.253Z","module_hash":"fc0d7db2a5f7872ae0d9228a19c7314b4f46f7574c53b2a168a62b986c43a31e","functions":[{"id":"func/MemoFollow.constructor","name":"MemoFollow.constructor","line":35,"end_line":38,"hash":"9407b43605444074011b1da595c9d53356352c72b0d847e00365d79ad705663a"},{"id":"func/MemoFollow.validate","name":"MemoFollow.validate","line":42,"end_line":57,"hash":"4154af442c36324ba147dff352c55610397fb430c9b62fbbe44728ab0e379179"},{"id":"func/MemoFollow.follow","name":"MemoFollow.follow","line":60,"end_line":62,"hash":"e24f69ef420d1ef625c2d03eae6014c824fdb35438a87e379fdc41747bbd321d"},{"id":"func/MemoFollow.unfollow","name":"MemoFollow.unfollow","line":65,"end_line":67,"hash":"48e93e85645bbcd767467afb807625b4adf6d6076f02fc841c91f58147bb44c7"},{"id":"func/MemoFollow._broadcastAction","name":"MemoFollow._broadcastAction","line":70,"end_line":88,"hash":"3720e2b6d78265383728bd7c5fcafeb018fad9c17a8bede12a6d4ffc3415cd3a"},{"id":"func/MemoFollow._toHash160","name":"MemoFollow._toHash160","line":92,"end_line":94,"hash":"3ed2ba4853b718a8316345c9f988ed3bed3ef647de3fd9761ee3c9e0bee86070"},{"id":"func/MemoFollow._ensureBchjs","name":"MemoFollow._ensureBchjs","line":96,"end_line":100,"hash":"92828d9038c9a4d367e80edd7f129291e434d57aae80b332081a66af9896a5d6"},{"id":"func/MemoFollow.reflect","name":"MemoFollow.reflect","line":104,"end_line":109,"hash":"af3f0ead1a9f51724e3c252122b3bf13c5323a3b9da244dee87a34815a90c94c"}]}
+// {"version":1,"tested_at":"2026-09-04T18:27:18.336Z","module_hash":"cc36dc8387a54f50e91393bcb10382515e66a0cfc74fb4f51412fac4df580136","functions":[{"id":"func/followConfig","name":"followConfig","line":25,"end_line":35,"hash":"6843e108f72a95c18267d1ecea29fdfbdb0814ce4b5e3672f22df612e6ecaccd"},{"id":"func/MemoFollow.follow","name":"MemoFollow.follow","line":41,"end_line":43,"hash":"82635824a8e221e587b74b22fea454d2f661e599d8c9b9d0d7ec7c14e214cbd7"},{"id":"func/MemoFollow.unfollow","name":"MemoFollow.unfollow","line":46,"end_line":48,"hash":"fa99fa77d68a875092f5aad8323dca42de06dff49af469c6d7db94f7033399b5"}]}
 // mutate4javascript-manifest-end
diff --git a/psf-memo-client/src/services/memo-mute.js b/psf-memo-client/src/services/memo-mute.js
index 892a796..d8f7f20 100644
--- a/psf-memo-client/src/services/memo-mute.js
+++ b/psf-memo-client/src/services/memo-mute.js
@@ -16,105 +16,44 @@
     PK_HASH_LENGTH     : size of the mutee hash160 in bytes (20)
 */
 
-const MemoAction = require('./memo-action')
+const MemoStateAction = require('./memo-state-action')
 
 const MEMO_MUTE_PREFIX = '6d16'
 const MEMO_UNMUTE_PREFIX = '6d17'
-const PK_HASH_LENGTH = 20
 
-class MemoMute extends MemoAction {
-  static config = {
+// Compose the static config for this Memo state action.
+function muteConfig () {
+  return {
     prefix: MEMO_MUTE_PREFIX,
     walletRequiredMsg: 'Memo mute requires a wallet.',
     lengthMessage: 'Mute address is invalid.',
     emptyMessage: 'Mute address is required.',
     lengthCode: 'mute_validation',
-    validationCode: 'mute_validation'
+    validationCode: 'mute_validation',
+    reflectMethod: 'setMuteState'
   }
+}
 
-  constructor (deps = {}) {
-    super(deps)
-    this.profiles = deps.profiles
-  }
-
-  // Validate a candidate cash address. Returns { ok: true } or throws a typed
-  // validation error.
-  validate (addr) {
-    if (typeof addr !== 'string' || addr.trim().length === 0) {
-      const err = new Error(this.emptyMessage)
-      err.code = this.validationCode
-      throw err
-    }
-
-    try {
-      this._toHash160(addr)
-      return { ok: true }
-    } catch (err) {
-      const validationErr = new Error(`Invalid cash address: ${addr}`)
-      validationErr.code = this.validationCode
-      throw validationErr
-    }
-  }
+class MemoMute extends MemoStateAction {
+  static config = muteConfig()
 
   // Broadcast a Memo mute for the given mutee address.
   async mute (muteeAddr) {
-    return this._broadcastAction(muteeAddr, MEMO_MUTE_PREFIX, true)
+    return this._setState(muteeAddr, MEMO_MUTE_PREFIX, true)
   }
 
   // Broadcast a Memo unmute for the given mutee address.
   async unmute (muteeAddr) {
-    return this._broadcastAction(muteeAddr, MEMO_UNMUTE_PREFIX, false)
-  }
-
-  // Internal: validate, broadcast, and reflect a mute/unmute action.
-  async _broadcastAction (muteeAddr, prefix, isMute) {
-    if (!this.wallet) {
-      throw new Error(this.walletRequiredMsg)
-    }
-    this._ensureBchjs()
-
-    this.validate(muteeAddr)
-
-    await this.wallet.getUtxos()
-
-    const hash160 = this._toHash160(muteeAddr)
-    const raw = Buffer.from(hash160, 'hex')
-
-    const txid = await this.wallet.sendOpReturn(raw, prefix)
-
-    this.reflect(txid, muteeAddr, isMute)
-
-    return txid
-  }
-
-  // Convert a cash address to its 20-byte hash160 hex string using the wallet's
-  // embedded bch-js.
-  _toHash160 (addr) {
-    return this.wallet.bchjs.Address.toHash160(addr)
-  }
-
-  _ensureBchjs () {
-    if (!this.wallet.bchjs || typeof this.wallet.bchjs.Address.toHash160 !== 'function') {
-      throw new Error('Wallet does not expose bch-js Address.toHash160.')
-    }
-  }
-
-  // Record the new mute state on the injected profile store when it exposes
-  // the mute methods.
-  reflect (txid, muteeAddr, isMute) {
-    if (this.profiles && typeof this.profiles.setMuteState === 'function') {
-      const myAddr = this.wallet?.walletInfo?.cashAddress
-      this.profiles.setMuteState(myAddr, muteeAddr, isMute)
-    }
+    return this._setState(muteeAddr, MEMO_UNMUTE_PREFIX, false)
   }
 }
 
 MemoMute.MEMO_MUTE_PREFIX = MEMO_MUTE_PREFIX
 MemoMute.MEMO_UNMUTE_PREFIX = MEMO_UNMUTE_PREFIX
-MemoMute.PK_HASH_LENGTH = PK_HASH_LENGTH
+MemoMute.PK_HASH_LENGTH = MemoStateAction.PK_HASH_LENGTH
 
 module.exports = MemoMute
 
 // mutate4javascript-manifest-begin
-// {"version":1,"tested_at":"2026-08-29T03:07:20.508Z","module_hash":"33469aed44ef4e9225a9ea952c5cd9335f46a0b1c1298525b3fd51ae2f77f817","functions":[{"id":"func/MemoMute.constructor","name":"MemoMute.constructor","line":35,"end_line":38,"hash":"9407b43605444074011b1da595c9d53356352c72b0d847e00365d79ad705663a"},{"id":"func/MemoMute.validate","name":"MemoMute.validate","line":42,"end_line":57,"hash":"4154af442c36324ba147dff352c55610397fb430c9b62fbbe44728ab0e379179"},{"id":"func/MemoMute.mute","name":"MemoMute.mute","line":60,"end_line":62,"hash":"60306e96a5b6ef4bac8cf3fc516785880b2ccab835730019bbd4b9bbfa27e464"},{"id":"func/MemoMute.unmute","name":"MemoMute.unmute","line":65,"end_line":67,"hash":"f6476de3d8b62b3f5e864dc83d005452bc9842d9accfed2c64f57082e0fec7b3"},{"id":"func/MemoMute._broadcastAction","name":"MemoMute._broadcastAction","line":70,"end_line":88,"hash":"05f7860e1db59b7611027186c859d790f8d8c74b150daf3b687a8c9dc453f751"},{"id":"func/MemoMute._toHash160","name":"MemoMute._toHash160","line":92,"end_line":94,"hash":"3ed2ba4853b718a8316345c9f988ed3bed3ef647de3fd9761ee3c9e0bee86070"},{"id":"func/MemoMute._ensureBchjs","name":"MemoMute._ensureBchjs","line":96,"end_line":100,"hash":"92828d9038c9a4d367e80edd7f129291e434d57aae80b332081a66af9896a5d6"},{"id":"func/MemoMute.reflect","name":"MemoMute.reflect","line":104,"end_line":109,"hash":"6053ec62558bbc19bd5e55b19541a6fe5cde28fe6fbf7c4eede209652e835bc4"}]}
+// {"version":1,"tested_at":"2026-09-04T18:27:53.801Z","module_hash":"05cb4f14173db9584533e58f931d775a2505d844f53bd29724935c3de083c40b","functions":[{"id":"func/muteConfig","name":"muteConfig","line":25,"end_line":35,"hash":"f05b5b03c441735322cdb433417ae5351626ed4c7d1db0a94cbf350f6818a605"},{"id":"func/MemoMute.mute","name":"MemoMute.mute","line":41,"end_line":43,"hash":"ad4c0ae3933e732017a59814bc6b9f6e7d263669f59440f1010209403ce0066f"},{"id":"func/MemoMute.unmute","name":"MemoMute.unmute","line":46,"end_line":48,"hash":"758b2676537ce5861f94ca9efff5b98a946bd82c023964e4d0c40f90d0a1261a"}]}
 // mutate4javascript-manifest-end
diff --git a/psf-memo-client/src/services/memo-state-action.js b/psf-memo-client/src/services/memo-state-action.js
new file mode 100644
index 0000000..7c8cdc2
--- /dev/null
+++ b/psf-memo-client/src/services/memo-state-action.js
@@ -0,0 +1,100 @@
+/*
+  Shared base for Memo follow/unfollow and mute/unmute (state) actions.
+
+  These actions all validate a cash address, convert it to its 20-byte
+  hash160, and broadcast an OP_RETURN carrying that hash160 payload with the
+  protocol prefix for a given state transition. On success they reflect the
+  new state on an injected profile store.
+
+  Subclasses extend MemoAction's config with the state-specific messages and
+  codes, plus `reflectMethod` naming which profile store method records the
+  new state, and expose thin methods (follow/unfollow or mute/unmute) that
+  delegate to the shared `_setState` helper with the appropriate prefix.
+
+  The wallet and an injected profile store are used so this module stays
+  testable and free of UI/network concerns; environmentally unsuitable I/O
+  lives behind those small adapter boundaries.
+*/
+
+const MemoAction = require('./memo-action')
+const { hexToBytes } = require('./hex')
+
+const PK_HASH_LENGTH = 20
+
+class MemoStateAction extends MemoAction {
+  constructor (deps = {}) {
+    super(deps)
+    this.profiles = deps.profiles
+  }
+
+  // Validate a candidate cash address. Returns { ok: true } or throws a typed
+  // validation error.
+  validate (addr) {
+    if (typeof addr !== 'string' || addr.trim().length === 0) {
+      const err = new Error(this.emptyMessage)
+      err.code = this.validationCode
+      throw err
+    }
+
+    try {
+      this._toHash160(addr)
+      return { ok: true }
+    } catch (err) {
+      const validationErr = new Error(`Invalid cash address: ${addr}`)
+      validationErr.code = this.validationCode
+      throw validationErr
+    }
+  }
+
+  // Internal: validate, broadcast, and reflect a state transition. Subclasses
+  // delegate their public methods here with the transition's prefix.
+  async _setState (targetAddr, prefix, state) {
+    if (!this.wallet) {
+      throw new Error(this.walletRequiredMsg)
+    }
+    this._ensureBchjs()
+
+    this.validate(targetAddr)
+
+    await this.wallet.getUtxos()
+
+    const hash160 = this._toHash160(targetAddr)
+    const raw = hexToBytes(hash160, PK_HASH_LENGTH, 'Address hash160')
+
+    const txid = await this.wallet.sendOpReturn(raw, prefix)
+
+    this.reflect(txid, targetAddr, state)
+
+    return txid
+  }
+
+  // Convert a cash address to its 20-byte hash160 hex string using the wallet's
+  // embedded bch-js.
+  _toHash160 (addr) {
+    return this.wallet.bchjs.Address.toHash160(addr)
+  }
+
+  _ensureBchjs () {
+    if (!this.wallet.bchjs || typeof this.wallet.bchjs.Address.toHash160 !== 'function') {
+      throw new Error('Wallet does not expose bch-js Address.toHash160.')
+    }
+  }
+
+  // Record the new state on the injected profile store method named by the
+  // subclass config.
+  reflect (txid, targetAddr, state) {
+    const reflectMethod = this.constructor.config.reflectMethod
+    if (this.profiles && typeof this.profiles[reflectMethod] === 'function') {
+      const myAddr = this.wallet?.walletInfo?.cashAddress
+      this.profiles[reflectMethod](myAddr, targetAddr, state)
+    }
+  }
+}
+
+MemoStateAction.PK_HASH_LENGTH = PK_HASH_LENGTH
+
+module.exports = MemoStateAction
+
+// mutate4javascript-manifest-begin
+// {"version":1,"tested_at":"2026-09-04T18:28:28.750Z","module_hash":"938e453562e0258b383cbc31f449fccc2e6105c805c97c52fb13bef3ee0fe6b4","functions":[{"id":"func/MemoStateAction.constructor","name":"MemoStateAction.constructor","line":25,"end_line":28,"hash":"9407b43605444074011b1da595c9d53356352c72b0d847e00365d79ad705663a"},{"id":"func/MemoStateAction.validate","name":"MemoStateAction.validate","line":32,"end_line":47,"hash":"4154af442c36324ba147dff352c55610397fb430c9b62fbbe44728ab0e379179"},{"id":"func/MemoStateAction._setState","name":"MemoStateAction._setState","line":51,"end_line":69,"hash":"86b976bcbe8532f7bfb9bdc989976f2266bce3d0e8c3a77a1f3e0b8413951684"},{"id":"func/MemoStateAction._toHash160","name":"MemoStateAction._toHash160","line":73,"end_line":75,"hash":"3ed2ba4853b718a8316345c9f988ed3bed3ef647de3fd9761ee3c9e0bee86070"},{"id":"func/MemoStateAction._ensureBchjs","name":"MemoStateAction._ensureBchjs","line":77,"end_line":81,"hash":"92828d9038c9a4d367e80edd7f129291e434d57aae80b332081a66af9896a5d6"},{"id":"func/MemoStateAction.reflect","name":"MemoStateAction.reflect","line":85,"end_line":91,"hash":"4ef0ab37e0ab08a681475805c5e53a010b35aa56560bc84f6d2189154ed7fa7d"}]}
+// mutate4javascript-manifest-end
diff --git a/psf-memo-client/test/property/follow.property.test.js b/psf-memo-client/test/property/follow.property.test.js
index b795192..90000d3 100644
--- a/psf-memo-client/test/property/follow.property.test.js
+++ b/psf-memo-client/test/property/follow.property.test.js
@@ -24,6 +24,10 @@ const rng = seededRandom(20260830)
 const MY_ADDRESS = 'bitcoincash:qqlrzp23w08434twmvr4fxw672whkjy0py26r63g3d'
 const CHARS = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l'
 
+function broadcastHex (wallet, index = 0) {
+  return Buffer.from(wallet.broadcasts[index].msg).toString('hex')
+}
+
 // Deterministic 20-byte hash160 hex for any input string, mirroring what a
 // real wallet's bch-js produces for a valid cash address.
 function hash20 (s) {
@@ -86,9 +90,9 @@ test('follow broadcasts exactly one hash160 payload with the follow prefix', asy
 
       return wallet.broadcasts.length === 1 &&
         wallet.broadcasts[0].prefix === MemoFollow.MEMO_FOLLOW_PREFIX &&
-        Buffer.isBuffer(wallet.broadcasts[0].msg) &&
+        wallet.broadcasts[0].msg instanceof Uint8Array &&
         wallet.broadcasts[0].msg.length === MemoFollow.PK_HASH_LENGTH &&
-        wallet.broadcasts[0].msg.toString('hex') === hash20(addr)
+        broadcastHex(wallet, 0) === hash20(addr)
     },
     { label: 'follow broadcast conservation and hash160 length' }
   )
@@ -104,9 +108,9 @@ test('unfollow broadcasts exactly one hash160 payload with the unfollow prefix',
 
       return wallet.broadcasts.length === 1 &&
         wallet.broadcasts[0].prefix === MemoFollow.MEMO_UNFOLLOW_PREFIX &&
-        Buffer.isBuffer(wallet.broadcasts[0].msg) &&
+        wallet.broadcasts[0].msg instanceof Uint8Array &&
         wallet.broadcasts[0].msg.length === MemoFollow.PK_HASH_LENGTH &&
-        wallet.broadcasts[0].msg.toString('hex') === hash20(addr)
+        broadcastHex(wallet, 0) === hash20(addr)
     },
     { label: 'unfollow broadcast conservation and hash160 length' }
   )
diff --git a/psf-memo-client/test/property/mute-services.property.test.js b/psf-memo-client/test/property/mute-services.property.test.js
index 65f6f3e..e9b557d 100644
--- a/psf-memo-client/test/property/mute-services.property.test.js
+++ b/psf-memo-client/test/property/mute-services.property.test.js
@@ -24,6 +24,10 @@ const rng = seededRandom(20260830)
 const MY_ADDRESS = 'bitcoincash:qqlrzp23w08434twmvr4fxw672whkjy0py26r63g3d'
 const CHARS = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l'
 
+function broadcastHex (wallet, index = 0) {
+  return Buffer.from(wallet.broadcasts[index].msg).toString('hex')
+}
+
 // Deterministic 20-byte hash160 hex for any input string, mirroring what a
 // real wallet's bch-js produces for a valid cash address.
 function hash20 (s) {
@@ -86,9 +90,9 @@ test('mute broadcasts exactly one hash160 payload with the mute prefix', async (
 
       return wallet.broadcasts.length === 1 &&
         wallet.broadcasts[0].prefix === MemoMute.MEMO_MUTE_PREFIX &&
-        Buffer.isBuffer(wallet.broadcasts[0].msg) &&
+        wallet.broadcasts[0].msg instanceof Uint8Array &&
         wallet.broadcasts[0].msg.length === MemoMute.PK_HASH_LENGTH &&
-        wallet.broadcasts[0].msg.toString('hex') === hash20(addr)
+        broadcastHex(wallet, 0) === hash20(addr)
     },
     { label: 'mute broadcast conservation and hash160 length' }
   )
@@ -104,9 +108,9 @@ test('unmute broadcasts exactly one hash160 payload with the unmute prefix', asy
 
       return wallet.broadcasts.length === 1 &&
         wallet.broadcasts[0].prefix === MemoMute.MEMO_UNMUTE_PREFIX &&
-        Buffer.isBuffer(wallet.broadcasts[0].msg) &&
+        wallet.broadcasts[0].msg instanceof Uint8Array &&
         wallet.broadcasts[0].msg.length === MemoMute.PK_HASH_LENGTH &&
-        wallet.broadcasts[0].msg.toString('hex') === hash20(addr)
+        broadcastHex(wallet, 0) === hash20(addr)
     },
     { label: 'unmute broadcast conservation and hash160 length' }
   )
diff --git a/psf-memo-client/test/unit/memo-follow.test.js b/psf-memo-client/test/unit/memo-follow.test.js
index 216b07c..4c73272 100644
--- a/psf-memo-client/test/unit/memo-follow.test.js
+++ b/psf-memo-client/test/unit/memo-follow.test.js
@@ -17,6 +17,10 @@ const MY_ADDRESS = 'bitcoincash:qqlrzp23w08434twmvr4fxw672whkjy0py26r63g3d'
 const FOLLOWEE_ADDRESS = 'bitcoincash:qr95sy3j9xwd2ap32xkykttr4cvcu7as4y0qverfuy'
 const FOLLOWEE_HASH160 = 'cb481232299cd5743151ac4b2d63ae198e7bb0a9'
 
+function broadcastHex (wallet, index = 0) {
+  return Buffer.from(wallet.broadcasts[index].msg).toString('hex')
+}
+
 function makeBchjs () {
   return {
     Address: {
@@ -63,8 +67,8 @@ test('follow broadcasts with the Memo follow prefix and hash160 payload', async
 
   assert.equal(wallet.broadcasts.length, 1)
   assert.equal(wallet.broadcasts[0].prefix, MemoFollow.MEMO_FOLLOW_PREFIX)
-  assert.ok(Buffer.isBuffer(wallet.broadcasts[0].msg))
-  assert.equal(wallet.broadcasts[0].msg.toString('hex'), FOLLOWEE_HASH160)
+  assert.equal(wallet.broadcasts[0].msg.length, MemoFollow.PK_HASH_LENGTH)
+  assert.equal(broadcastHex(wallet, 0), FOLLOWEE_HASH160)
 })
 
 test('unfollow broadcasts with the Memo unfollow prefix and hash160 payload', async () => {
@@ -75,7 +79,8 @@ test('unfollow broadcasts with the Memo unfollow prefix and hash160 payload', as
 
   assert.equal(wallet.broadcasts.length, 1)
   assert.equal(wallet.broadcasts[0].prefix, MemoFollow.MEMO_UNFOLLOW_PREFIX)
-  assert.equal(wallet.broadcasts[0].msg.toString('hex'), FOLLOWEE_HASH160)
+  assert.equal(wallet.broadcasts[0].msg.length, MemoFollow.PK_HASH_LENGTH)
+  assert.equal(broadcastHex(wallet, 0), FOLLOWEE_HASH160)
 })
 
 test('follow reflects the new follow state on the profile store', async () => {
diff --git a/psf-memo-client/test/unit/memo-mute.test.js b/psf-memo-client/test/unit/memo-mute.test.js
index 896f70e..7553724 100644
--- a/psf-memo-client/test/unit/memo-mute.test.js
+++ b/psf-memo-client/test/unit/memo-mute.test.js
@@ -12,6 +12,10 @@ const MY_ADDRESS = 'bitcoincash:qqlrzp23w08434twmvr4fxw672whkjy0py26r63g3d'
 const MUTEE_ADDRESS = 'bitcoincash:qr95sy3j9xwd2ap32xkykttr4cvcu7as4y0qverfuy'
 const MUTEE_HASH160 = 'cb481232299cd5743151ac4b2d63ae198e7bb0a9'
 
+function broadcastHex (wallet, index = 0) {
+  return Buffer.from(wallet.broadcasts[index].msg).toString('hex')
+}
+
 function makeBchjs () {
   return {
     Address: {
@@ -58,8 +62,8 @@ test('mute broadcasts with the Memo mute prefix and hash160 payload', async () =
 
   assert.equal(wallet.broadcasts.length, 1)
   assert.equal(wallet.broadcasts[0].prefix, MemoMute.MEMO_MUTE_PREFIX)
-  assert.ok(Buffer.isBuffer(wallet.broadcasts[0].msg))
-  assert.equal(wallet.broadcasts[0].msg.toString('hex'), MUTEE_HASH160)
+  assert.equal(wallet.broadcasts[0].msg.length, MemoMute.PK_HASH_LENGTH)
+  assert.equal(broadcastHex(wallet, 0), MUTEE_HASH160)
 })
 
 test('unmute broadcasts with the Memo unmute prefix and hash160 payload', async () => {
@@ -70,7 +74,8 @@ test('unmute broadcasts with the Memo unmute prefix and hash160 payload', async
 
   assert.equal(wallet.broadcasts.length, 1)
   assert.equal(wallet.broadcasts[0].prefix, MemoMute.MEMO_UNMUTE_PREFIX)
-  assert.equal(wallet.broadcasts[0].msg.toString('hex'), MUTEE_HASH160)
+  assert.equal(wallet.broadcasts[0].msg.length, MemoMute.PK_HASH_LENGTH)
+  assert.equal(broadcastHex(wallet, 0), MUTEE_HASH160)
 })
 
 test('mute reflects the new mute state on the profile store', async () => {