feat(deploy): add HF-router Llama-3.3-70B mainnet supplier (hf-llama33)

OpenAI-compatible supplier backed by the HuggingFace Inference Providers router
(meta-llama/Llama-3.3-70B-Instruct, llm.text.generate.v1). Config only; mirrors
the glm one-off template with OPENAI_BASE_URL=https://router.huggingface.co.

- deploy/mainnet/docker-compose.supplier-hf-llama33.yml
- register the supplier wallet in monitor-wallets OPERATOR_SOURCES

The env file (supplier/.env.hf-llama33) holds the wallet key + HF token and is
never committed; wallet-monitor/wallets.json is gitignored runtime data.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

buyer/scripts/monitor-wallets.ts

@@ -41,6 +41,13 @@ interface OperatorSource {
 }
 
 const OPERATOR_SOURCES: OperatorSource[] = [
+  {
+    label: "supplier-hf-llama33@vector-marketplace",
+    host: "root@91.98.147.172",
+    envPath: "/root/agents-marketplace/supplier/.env.hf-llama33",
+    keyVar: "SUPPLIER_PRIV_KEY_HEX",
+    role: "supplier",
+  },
   {
     label: "buyer@vector-marketplace",
     host: "root@91.98.147.172",

deploy/mainnet/docker-compose.supplier-hf-llama33.yml

@@ -0,0 +1,92 @@
+# deploy/mainnet/docker-compose.supplier-hf-llama33.yml — Supplier — MAINNET
+#   (HuggingFace Inference Providers router / meta-llama/Llama-3.3-70B-Instruct
+#    — one-off `llm.text.generate.v1`)
+#
+# HF-router-backed supplier. LLM_BACKEND=openai pointed at the HuggingFace
+# Inference Providers router (OpenAI-compatible at https://router.huggingface.co).
+# No local proxy container — reachable over public HTTPS. Direct analogue of the
+# OpenRouter/Hetzner-backed suppliers; the router is OpenAI-compatible so this is
+# config only (V1 HF integration).
+#
+# Pre-flight:
+#   1. DNS: mp-suppliers-hf-llama33.vector.apexfusion.org → host
+#      (individual DNS-only A record → 91.98.147.172; NO wildcard exists —
+#       letsencrypt HTTP-01 issuance needs the unproxied direct record)
+#   2. supplier/.env.hf-llama33 written on host (chmod 600) with at minimum:
+#        SUPPLIER_PRIV_KEY_HEX, SUPPLIER_ADDRESS, SUPPLIER_PKH,
+#        SUPPLIER_PUB_KEY_HEX, OPENAI_API_KEY (hf_ token), OGMIOS_URL,
+#        NETWORK_ID=1, VECTOR_ZERO_TIME_MS, ESCROW_REF_UTXO, ADVERT_REF_UTXO,
+#        ADVERT_REF, LIVE_CHAIN=1
+#      Advert posted with --capability-id llm.text.generate.v1.
+#      Do NOT set OPENAI_REASONING — the HF router rejects it (HTTP 400) and the
+#      supplier's config guard refuses to boot.
+#   3. Networks already exist (created by the canonical supplier compose):
+#        docker network create marketplace-mainnet-net   # one-shot
+#        # traefik-net is created by the Traefik project
+
+name: marketplace-mainnet-supplier-hf-llama33
+
+services:
+  supplier:
+    build:
+      context: ../..
+      dockerfile: supplier/Dockerfile
+    container_name: marketplace-mainnet-supplier-hf-llama33
+    restart: unless-stopped
+    env_file:
+      # Self-contained env for this HF-router-backed variant. Holds this
+      # supplier's distinct SUPPLIER_PRIV_KEY_HEX (+ derived wallet vars),
+      # ADVERT_REF, the HF OPENAI_API_KEY, and the shared mainnet plumbing
+      # duplicated in full (NETWORK_ID, OGMIOS_URL, VECTOR_ZERO_TIME_MS,
+      # ref-script UTxOs, LIVE_CHAIN). No env_file ordering / override magic.
+      - path: ../../supplier/.env.hf-llama33
+        required: false
+    environment:
+      LLM_BACKEND: openai
+      # No /v1 suffix — supplier/src/openai.ts appends /v1/chat/completions
+      # (HF router serves at https://router.huggingface.co/v1/...).
+      OPENAI_BASE_URL: https://router.huggingface.co
+      # First-token latency across hosted providers can exceed local backends;
+      # kept ≤ the advert's max_processing_ms (300000) per fleet footgun #4.
+      OPENAI_TIMEOUT_MS: "300000"
+      # OPENAI_MAX_TOKENS intentionally unset: no max_tokens forwarded upstream,
+      # the provider grants context − prompt. Advert cap = model context length.
+      PORT: "8080"
+      # Enable LiveOgmiosProvider so submitTx/awaitTx actually broadcast.
+      LIVE_CHAIN: "1"
+      # NETWORK_ID and OGMIOS_URL intentionally not pinned here — they MUST
+      # come from the operator-provided supplier/.env.hf-llama33 on a mainnet host.
+    healthcheck:
+      test: ["CMD-SHELL", "wget -qO- http://localhost:8080/healthz >/dev/null || exit 1"]
+      interval: 20s
+      timeout: 5s
+      retries: 3
+      start_period: 15s
+    networks:
+      - marketplace-mainnet-net
+      - traefik-net
+    labels:
+      - "traefik.enable=true"
+      - "traefik.docker.network=traefik-net"
+      - "traefik.http.routers.mp-suppliers-hf-llama33-mainnet.entrypoints=web"
+      - "traefik.http.routers.mp-suppliers-hf-llama33-mainnet.rule=Host(`mp-suppliers-hf-llama33.vector.apexfusion.org`)"
+      - "traefik.http.routers.mp-suppliers-hf-llama33-mainnet.middlewares=mp-suppliers-hf-llama33-mainnet-https"
+      - "traefik.http.middlewares.mp-suppliers-hf-llama33-mainnet-https.redirectscheme.scheme=https"
+      - "traefik.http.middlewares.mp-suppliers-hf-llama33-mainnet-https.redirectscheme.permanent=true"
+      - "traefik.http.routers.mp-suppliers-hf-llama33-mainnet-tls.entrypoints=websecure"
+      - "traefik.http.routers.mp-suppliers-hf-llama33-mainnet-tls.rule=Host(`mp-suppliers-hf-llama33.vector.apexfusion.org`)"
+      - "traefik.http.routers.mp-suppliers-hf-llama33-mainnet-tls.tls.certresolver=letsencrypt"
+      - "traefik.http.services.mp-suppliers-hf-llama33-mainnet.loadbalancer.server.port=8080"
+    logging:
+      driver: json-file
+      options:
+        max-size: "10m"
+        max-file: "3"
+
+networks:
+  marketplace-mainnet-net:
+    external: true
+    name: marketplace-mainnet-net
+  traefik-net:
+    external: true
+    name: traefik-net

gateway/src/sdk/registry.ts

@@ -15,19 +15,88 @@ import { open as unseal } from "../crypto/seal.js";
 import { deriveWalletKey } from "../wallet.js";
 import type { ApiKeyRow } from "../db/store.js";
 
-/** Tiny promise-chain mutex: run(fn) executes fns strictly one at a time. */
+/** Default per-run deadline. Chain reads and tx submits settle in seconds;
+ * anything past this is the 2026-08-12 freeze mode (a fetch that never
+ * settles), not a slow success. */
+export const DEFAULT_MUTEX_TIMEOUT_MS = 180_000;
+
+/** Default queue bound per mutex. A healthy key drains its queue in seconds;
+ * a queue this deep means the head is stuck and callers should fail fast. */
+export const DEFAULT_MUTEX_MAX_QUEUE = 64;
+
+/** A run() exceeded its deadline and was abandoned so queued work can proceed. */
+export class MutexTimeoutError extends Error {
+  constructor(label: string, timeoutMs: number) {
+    super(`mutex run '${label}' exceeded ${timeoutMs}ms and was abandoned; queued work proceeds`);
+    this.name = "MutexTimeoutError";
+  }
+}
+
+/** run() was refused because the queue is at its bound (head likely stuck). */
+export class MutexQueueFullError extends Error {
+  constructor(label: string, depth: number) {
+    super(`mutex queue full (${depth} pending) — refusing '${label}'; the head of the queue is likely stuck`);
+    this.name = "MutexQueueFullError";
+  }
+}
+
+function runWithDeadline<T>(fn: () => Promise<T>, timeoutMs: number, label: string): Promise<T> {
+  return new Promise<T>((resolvePromise, rejectPromise) => {
+    const timer = setTimeout(() => rejectPromise(new MutexTimeoutError(label, timeoutMs)), timeoutMs);
+    // Node-only nicety: don't hold the process open for a pending deadline.
+    timer.unref?.();
+    fn().then(
+      (v) => {
+        clearTimeout(timer);
+        resolvePromise(v);
+      },
+      (e) => {
+        clearTimeout(timer);
+        rejectPromise(e);
+      },
+    );
+  });
+}
+
+/**
+ * Tiny promise-chain mutex: run(fn) executes fns strictly one at a time —
+ * now with a per-run deadline and a queue bound (2026-08-12 freeze fix).
+ *
+ * On deadline the stuck fn is NOT cancelled (promises aren't); it is
+ * abandoned: its run() rejects with MutexTimeoutError and the chain advances.
+ * A zombie that settles later can at worst lose a UTxO-contention race with
+ * the run that replaced it — strictly better than the alternative, where one
+ * stuck chain call convoys every subsequent request on the key forever.
+ */
 export class Mutex {
   private tail: Promise<unknown> = Promise.resolve();
+  private depth = 0;
 
-  run<T>(fn: () => Promise<T>): Promise<T> {
-    const result = this.tail.then(fn, fn);
-    // Keep the chain alive even if fn rejects; swallow here so the next
-    // run() isn't poisoned by a prior rejection.
-    this.tail = result.then(
+  constructor(private readonly opts: { timeoutMs?: number; maxQueue?: number } = {}) {}
+
+  run<T>(fn: () => Promise<T>, label = "op"): Promise<T> {
+    const timeoutMs = this.opts.timeoutMs ?? DEFAULT_MUTEX_TIMEOUT_MS;
+    const maxQueue = this.opts.maxQueue ?? DEFAULT_MUTEX_MAX_QUEUE;
+
+    if (this.depth >= maxQueue) {
+      return Promise.reject(new MutexQueueFullError(label, this.depth));
+    }
+    this.depth++;
+
+    // Keep the chain alive even if fn rejects or times out; swallow here so
+    // the next run() isn't poisoned by a prior rejection.
+    const result = this.tail.then(
+      () => runWithDeadline(fn, timeoutMs, label),
+      () => runWithDeadline(fn, timeoutMs, label),
+    );
+    const settled = result.finally(() => {
+      this.depth--;
+    });
+    this.tail = settled.then(
       () => undefined,
       () => undefined,
     );
-    return result;
+    return settled;
   }
 }
 

packages/shared/src/tx/escrow/release.ts

@@ -17,6 +17,8 @@ import type { WalletKey, BuildResult } from "../types.js";
 import { TxConstructionError } from "../types.js";
 import { encodeTxBody, sha256Hex } from "../internal/testTxBody.js";
 import { ACCEPT_WINDOW_MS, mockSlotToWallclockMs } from "../internal/constants.js";
+import { detectCborBackend } from "../internal/cborBackend.js";
+import type { LiveOgmiosProvider } from "../../chain/LiveOgmiosProvider.js";
 
 export interface ReleaseParams {
   chain: ChainProvider;
@@ -65,8 +67,10 @@ export async function buildReleaseTx(
   }
 
   // 4. Tip must be at or past submitted_at + ACCEPT_WINDOW.
+  // Live backend uses real POSIX ms; mock backend keeps slot*1000.
   const tipSlot = await chain.tip();
-  const tipMs = mockSlotToWallclockMs(tipSlot);
+  const isLive = detectCborBackend(chain) === "live";
+  const tipMs = isLive ? Date.now() : mockSlotToWallclockMs(tipSlot);
   const threshold = datum.submitted_at + ACCEPT_WINDOW_MS;
   if (tipMs < threshold) {
     throw new TxConstructionError(
@@ -75,6 +79,21 @@ export async function buildReleaseTx(
     );
   }
 
+  // Live path: real Cardano CBOR via lucid-evolution.
+  if (isLive) {
+    const liveCborPath = "../internal/liveCbor.js";
+    const { buildLiveTxForRelease } = await import(/* @vite-ignore */ liveCborPath);
+    return buildLiveTxForRelease({
+      chain: chain as LiveOgmiosProvider,
+      supplierKey,
+      escrowRef,
+      escrowUtxo: utxo,
+      datum,
+      tipMs,
+    });
+  }
+
+  // Mock path: synthetic testTxBody (preserves existing test behaviour).
   const supplierDue =
     datum.payment_lovelace + datum.supplier_bond_lovelace + datum.buyer_bond_lovelace;
 

packages/shared/src/tx/internal/liveCbor.ts

@@ -10,8 +10,8 @@
  * for vkh enterprise). Input UTxOs may carry testnet-prefixed addresses — lucid
  * does not validate address network for inputs (only for outputs).
  *
- * Deferred builders (postAdvert, updateAdvert, retireAdvert, reclaim, release)
- * are NOT touched in M1-F-4. Those continue using the synthetic testTxBody path.
+ * Deferred builders: only updateAdvert remains on the synthetic testTxBody
+ * path. postAdvert, retireAdvert, reclaim, and release all have live builders.
  *
  * Catherine M1-F-4-green.
  */
@@ -61,6 +61,7 @@ const REDEEMER_CLAIM = 121;
 const REDEEMER_SUBMIT = 122;
 const REDEEMER_ACCEPT = 123;
 const REDEEMER_RECLAIM = 124;
+const REDEEMER_RELEASE = 125;
 
 // AdvertRedeemer Constr indices per lib/marketplace/types.ak:
 //   PostAdvert    → Constr0 (tag 121, creation event — never seen by spend)
@@ -121,6 +122,15 @@ export interface LiveReclaimParams {
   tipMs: number;
 }
 
+export interface LiveReleaseParams {
+  chain: LiveOgmiosProvider;
+  supplierKey: WalletKey;
+  escrowRef: OutputReference;
+  escrowUtxo: Utxo;
+  datum: EscrowDatum;
+  tipMs: number;
+}
+
 export interface LivePostAdvertParams {
   chain: LiveOgmiosProvider;
   walletKey: WalletKey;
@@ -778,6 +788,77 @@ export async function buildLiveTxForReclaim(params: LiveReclaimParams): Promise<
   return { txCborHex, expectedTxHash };
 }
 
+// ─── Release ─────────────────────────────────────────────────────────
+
+export async function buildLiveTxForRelease(params: LiveReleaseParams): Promise<BuildResult> {
+  const provider = buildLucidProvider(params.chain);
+  const { lucid } = await createLucidContext(provider, params.supplierKey, {
+    networkId: 1,
+    systemStartUnix: 0,
+    slotLengthMs: 1000,
+  }, { usePresetProtocolParameters: true });
+
+  const { script, address: escrowAddress } = loadEscrowScript();
+  const spendCtx = await resolveSpendCtx(lucid, "ESCROW_REF_UTXO", script);
+  const lucidInput = chainUtxoToLucidScriptInput(params.escrowUtxo, escrowAddress);
+  const releaseRedeemerHex = encodeNullaryConstrHex(REDEEMER_RELEASE);
+
+  if (params.datum.submitted_at === null) {
+    throw new TxConstructionError(
+      "submitted_at missing",
+      "Submitted-state escrow must carry a submitted_at timestamp",
+    );
+  }
+
+  // Release pays everything to the supplier: payment + supplier_bond + buyer_bond.
+  const supplierDue =
+    params.datum.payment_lovelace +
+    params.datum.supplier_bond_lovelace +
+    params.datum.buyer_bond_lovelace;
+  const supplierLovelace = supplierDue < MIN_UTXO_LOVELACE ? MIN_UTXO_LOVELACE : supplierDue;
+  const supplierAddress = pkhToEnterpriseAddress(params.datum.supplier_pkh, MAINNET_ID);
+
+  const realWalletUtxos = await lucid.wallet().getUtxos();
+  assertCollateralCandidate(realWalletUtxos);
+  const presetWalletInputs = realWalletUtxos;
+
+  // escrow.ak:handle_release checks `lower_bound >= submitted_at + ACCEPT_WINDOW`.
+  // Clamp validFrom to that threshold: the Reclaim-style tip-60s back-pad alone
+  // would violate the validator whenever the tip is less than 60s past the window.
+  const threshold = params.datum.submitted_at + ACCEPT_WINDOW_MS;
+  const validFromMs = Math.max(threshold, params.tipMs - 60_000);
+
+  let signed;
+  try {
+    const txBuilder = (
+      spendCtx.kind === "ref"
+        ? lucid.newTx().readFrom([spendCtx.refUtxo])
+        : lucid.newTx().attach.SpendingValidator(spendCtx.script)
+    )
+      .collectFrom([lucidInput], releaseRedeemerHex)
+      .pay.ToAddress(supplierAddress, { lovelace: supplierLovelace })
+      .addSignerKey(params.supplierKey.pubKeyHash)
+      .validFrom(validFromMs)
+      .validTo(params.tipMs + 60_000)
+      .setMinFee(500_000n);
+
+    // Same UPLC eval delegation as Accept/Reclaim — lucid's CML evaluator
+    // falsely rejects valid Plutus V3 spends; route to Ogmios.
+    const completed = await txBuilder.complete({
+      presetWalletInputs,
+      localUPLCEval: false,
+    });
+    signed = await completed.sign.withWallet().complete();
+  } catch (err) {
+    rethrowAsTxError(err, "release build failed");
+  }
+
+  const txCborHex = signed.toCBOR();
+  const expectedTxHash = signed.toHash();
+  await params.chain.submitTx(txCborHex);
+  return { txCborHex, expectedTxHash };
+}
+
 // ─── PostAdvert ──────────────────────────────────────────────────────
 
 export async function buildLiveTxForAdvert(

tests/unit/gateway-mutex.test.ts

@@ -0,0 +1,121 @@
+/**
+ * gateway-mutex.test.ts — Mutex deadline + queue bound (2026-08-12 freeze fix).
+ *
+ * Incident: one chain call that never settled, run under a per-key Mutex with
+ * no deadline, convoyed every subsequent request on that key silently while
+ * /models and /account stayed healthy. The fix gives run() a deadline that
+ * abandons the stuck operation (advancing the chain) and a queue bound that
+ * rejects new work instead of queueing without limit.
+ *
+ * Serialization semantics of the original class must be preserved.
+ */
+
+import { describe, it, expect, vi, afterEach } from "vitest";
+import {
+  Mutex,
+  MutexTimeoutError,
+  MutexQueueFullError,
+} from "../../gateway/src/sdk/registry.js";
+
+afterEach(() => {
+  vi.useRealTimers();
+});
+
+// ─── Preserved semantics ─────────────────────────────────────────────────────
+
+describe("Mutex — serialization (preserved semantics)", () => {
+  it("runs fns strictly one at a time, in order", async () => {
+    const mutex = new Mutex();
+    const order: number[] = [];
+    let firstRunning = false;
+
+    const first = mutex.run(async () => {
+      firstRunning = true;
+      await new Promise((r) => setTimeout(r, 20));
+      order.push(1);
+      firstRunning = false;
+    });
+    const second = mutex.run(async () => {
+      expect(firstRunning).toBe(false);
+      order.push(2);
+    });
+
+    await Promise.all([first, second]);
+    expect(order).toEqual([1, 2]);
+  });
+
+  it("a rejecting fn does not poison the chain", async () => {
+    const mutex = new Mutex();
+
+    await expect(mutex.run(async () => Promise.reject(new Error("boom")))).rejects.toThrow("boom");
+    await expect(mutex.run(async () => "alive")).resolves.toBe("alive");
+  });
+});
+
+// ─── Deadline (the freeze fix) ───────────────────────────────────────────────
+
+describe("Mutex — per-run deadline", () => {
+  it("rejects a stuck run with MutexTimeoutError once the deadline passes", async () => {
+    vi.useFakeTimers();
+    const mutex = new Mutex({ timeoutMs: 1_000 });
+
+    const stuck = mutex.run(() => new Promise<never>(() => {}), "stuck-chain-read");
+    // Attach the rejection expectation BEFORE advancing time so the rejection
+    // is not treated as unhandled.
+    const assertion = expect(stuck).rejects.toBeInstanceOf(MutexTimeoutError);
+
+    await vi.advanceTimersByTimeAsync(1_001);
+    await assertion;
+  });
+
+  it("queued work proceeds after a stuck run is abandoned (no convoy)", async () => {
+    vi.useFakeTimers();
+    const mutex = new Mutex({ timeoutMs: 1_000 });
+
+    const stuck = mutex.run(() => new Promise<never>(() => {}), "stuck");
+    const stuckAssertion = expect(stuck).rejects.toBeInstanceOf(MutexTimeoutError);
+    const queued = mutex.run(async () => "unblocked");
+
+    await vi.advanceTimersByTimeAsync(1_001);
+    await stuckAssertion;
+    await expect(queued).resolves.toBe("unblocked");
+  });
+
+  it("a run that finishes in time is unaffected by the deadline", async () => {
+    vi.useFakeTimers();
+    const mutex = new Mutex({ timeoutMs: 1_000 });
+
+    const quick = mutex.run(async () => "done");
+    await vi.advanceTimersByTimeAsync(1);
+    await expect(quick).resolves.toBe("done");
+  });
+});
+
+// ─── Queue bound ─────────────────────────────────────────────────────────────
+
+describe("Mutex — queue bound", () => {
+  it("rejects immediately with MutexQueueFullError when the queue is full", async () => {
+    const mutex = new Mutex({ maxQueue: 2 });
+    let releaseFirst!: () => void;
+    const gate = new Promise<void>((r) => {
+      releaseFirst = r;
+    });
+
+    const first = mutex.run(() => gate.then(() => "first"));
+    const second = mutex.run(async () => "second");
+    const third = mutex.run(async () => "third");
+
+    await expect(third).rejects.toBeInstanceOf(MutexQueueFullError);
+
+    releaseFirst();
+    await expect(first).resolves.toBe("first");
+    await expect(second).resolves.toBe("second");
+  });
+
+  it("slots free up once runs settle", async () => {
+    const mutex = new Mutex({ maxQueue: 1 });
+
+    await mutex.run(async () => "a");
+    await expect(mutex.run(async () => "b")).resolves.toBe("b");
+  });
+});

tests/unit/tx-release-live-dispatch.test.ts

@@ -0,0 +1,83 @@
+/**
+ * tx-release-live-dispatch.test.ts — buildReleaseTx() must route to the live
+ * CBOR builder when the chain is a LiveOgmiosProvider, mirroring reclaim.ts.
+ *
+ * Parity gap under test: Release is the one escrow spend path still hardwired
+ * to the synthetic testTxBody backend, which leaves Submitted-past-accept-window
+ * escrows unresolvable on mainnet (sweeper parks them "for supplier Release").
+ *
+ * The live builder itself needs a real wallet + Ogmios and is exercised by the
+ * mainnet fleet scripts like the other six builders; here it is mocked at the
+ * module boundary and only the dispatch contract is asserted.
+ */
+
+import { describe, it, expect, vi } from "vitest";
+
+vi.mock("../../packages/shared/src/tx/internal/liveCbor.js", () => ({
+  buildLiveTxForRelease: vi.fn(async () => ({
+    txCborHex: "live-cbor-sentinel",
+    expectedTxHash: "live-hash-sentinel",
+  })),
+}));
+
+import { buildReleaseTx } from "../../packages/shared/src/tx/escrow/release.js";
+import { LiveOgmiosProvider } from "../../packages/shared/src/chain/LiveOgmiosProvider.js";
+import { ACCEPT_WINDOW_MS } from "../../packages/shared/src/tx/escrow/accept.js";
+import * as liveCbor from "../../packages/shared/src/tx/internal/liveCbor.js";
+import { buildSupplierWalletKey } from "../fixtures/supplier-side/wallet-keys.js";
+import {
+  buildSubmittedEscrowUtxo,
+  SUBMITTED_AT,
+} from "../fixtures/buyer-side/sample-escrow-utxos.js";
+
+const RELEASE_THRESHOLD = SUBMITTED_AT + ACCEPT_WINDOW_MS;
+
+/**
+ * A stub that passes the `instanceof LiveOgmiosProvider` backend check without
+ * opening any connection. Only the methods buildReleaseTx touches pre-dispatch
+ * are provided. Tip slot is set past the accept window so that, while the
+ * dispatch gap exists, the mock path completes and returns synthetic CBOR
+ * (a clean assertion failure) instead of erroring on the window check.
+ */
+function fakeLiveChain(): LiveOgmiosProvider {
+  const utxo = buildSubmittedEscrowUtxo();
+  const fake = Object.create(LiveOgmiosProvider.prototype) as LiveOgmiosProvider;
+  Object.assign(fake, {
+    queryUtxo: async () => utxo,
+    tip: async () => Math.floor((RELEASE_THRESHOLD + 60_000) / 1000),
+    submitTx: async () => undefined,
+  });
+  return fake;
+}
+
+describe("buildReleaseTx() — live backend dispatch", () => {
+  it("routes to buildLiveTxForRelease when chain is a LiveOgmiosProvider", async () => {
+    const chain = fakeLiveChain();
+    const supplier = buildSupplierWalletKey();
+    const utxo = buildSubmittedEscrowUtxo();
+
+    const result = await buildReleaseTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
+
+    expect(result.txCborHex).toBe("live-cbor-sentinel");
+    expect(result.expectedTxHash).toBe("live-hash-sentinel");
+    expect(liveCbor.buildLiveTxForRelease).toHaveBeenCalledTimes(1);
+  });
+
+  it("passes the escrow UTxO, decoded datum, and a real-clock tipMs to the live builder", async () => {
+    const chain = fakeLiveChain();
+    const supplier = buildSupplierWalletKey();
+    const utxo = buildSubmittedEscrowUtxo();
+    const before = Date.now();
+
+    await buildReleaseTx({ chain, supplierKey: supplier, escrowRef: utxo.ref });
+
+    const mockFn = liveCbor.buildLiveTxForRelease as unknown as ReturnType<typeof vi.fn>;
+    const args = mockFn.mock.calls.at(-1)?.[0] as Record<string, unknown>;
+    expect(args.escrowUtxo).toEqual(utxo);
+    expect((args.datum as { state: string }).state).toBe("Submitted");
+    expect(args.supplierKey).toBe(supplier);
+    // Live path derives tipMs from the real clock (reclaim.ts parity), not
+    // from the mock slot→ms mapping.
+    expect(args.tipMs as number).toBeGreaterThanOrEqual(before);
+  });
+});