diff --git a/js/services/nip71MirrorService.js b/js/services/nip71MirrorService.js
new file mode 100644
index 00000000..dcb92e5d
--- /dev/null
+++ b/js/services/nip71MirrorService.js
@@ -0,0 +1,122 @@
+// Phase 1 of the NIP-71 interop plan (docs/nip71-migration-plan.md): publish the
+// opt-in addressable NIP-71 mirror (kind 34235/34236) for a bitvid video to the
+// user's write/outbox relays.
+//
+// Builds on the Phase 0 pure builder (buildNip71MirrorEvent) which already enforces
+// the "private never mirrored" and "HTTPS url required" rules. This service adds:
+//   - the site-wide NSFW gate: when ALLOW_NSFW_CONTENT is false, an instance that
+//     won't surface NSFW must not publish it outward either (moderation audit item).
+//   - signing with the active signer + publishing to the write (outbox) relay set.
+//
+// Dependency-injected so it unit-tests without a live signer/relay pool.
+
+import { buildNip71MirrorEvent } from "../nostr/nip71Mirror.js";
+import { nostrClient } from "../nostrClientFacade.js";
+import { getActiveSigner } from "../nostr/index.js";
+import {
+  publishEventToRelays as defaultPublishEventToRelays,
+  summarizePublishResults as defaultSummarize,
+} from "../nostrPublish.js";
+import { ALLOW_NSFW_CONTENT } from "../config.js";
+import { userLogger } from "../utils/logger.js";
+
+function str(value) {
+  return typeof value === "string" ? value.trim() : "";
+}
+
+export function createNip71MirrorService({
+  buildMirrorEvent = buildNip71MirrorEvent,
+  getActivePubkey = () => str(nostrClient?.pubkey),
+  getSigner = () => getActiveSigner(),
+  // Outbox/write set (mirrors getDeletePublishRelays from the delete work).
+  getWriteRelays = () =>
+    typeof nostrClient?.getDeletePublishRelays === "function"
+      ? nostrClient.getDeletePublishRelays()
+      : [],
+  getPool = () => nostrClient?.pool || null,
+  publishEventToRelays = defaultPublishEventToRelays,
+  summarizePublishResults = defaultSummarize,
+  signEvent = async (template) => {
+    const signer = getActiveSigner();
+    if (!signer || typeof signer.signEvent !== "function") {
+      const err = new Error("Active signer missing signEvent support.");
+      err.code = "sign-event-missing";
+      throw err;
+    }
+    return signer.signEvent(template);
+  },
+  // Instance policy: only mirror NSFW outward when the site permits NSFW.
+  allowNsfw = () => ALLOW_NSFW_CONTENT === true,
+  now = () => Date.now(),
+} = {}) {
+  function isAvailable() {
+    const pubkey = getActivePubkey();
+    const signer = getSigner();
+    return Boolean(pubkey) && Boolean(signer) && typeof signer.signEvent === "function";
+  }
+
+  // Whether a video is even eligible for the mirror (drives UI gating too).
+  function canMirror(video) {
+    if (!video || typeof video !== "object") {
+      return { ok: false, reason: "invalid" };
+    }
+    if (video.isPrivate === true) {
+      return { ok: false, reason: "private" };
+    }
+    if (video.isNsfw === true && !allowNsfw()) {
+      return { ok: false, reason: "nsfw-blocked" };
+    }
+    if (!/^https:\/\//i.test(str(video.url))) {
+      return { ok: false, reason: "no-url" };
+    }
+    return { ok: true };
+  }
+
+  async function publish(video, options = {}) {
+    if (!isAvailable()) {
+      return { ok: false, error: "unavailable" };
+    }
+    // Site NSFW policy gate (defense in depth alongside the UI not offering it).
+    if (video?.isNsfw === true && !allowNsfw()) {
+      return { ok: false, reason: "nsfw-blocked" };
+    }
+
+    const pubkey = str(video?.pubkey) || getActivePubkey();
+    const built = buildMirrorEvent(
+      { ...video, pubkey },
+      { ...options, createdAt: Math.floor(now() / 1000) },
+    );
+    if (!built.ok) {
+      return { ok: false, reason: built.reason };
+    }
+
+    let signed;
+    try {
+      signed = await signEvent(built.event);
+    } catch (error) {
+      userLogger.warn("[nip71Mirror] Failed to sign mirror event:", error);
+      return { ok: false, error: "sign-failed", cause: error };
+    }
+
+    const relays = getWriteRelays() || [];
+    const pool = getPool();
+    if (!pool || !relays.length) {
+      return { ok: false, error: "no-relays" };
+    }
+
+    const results = await publishEventToRelays(pool, relays, signed);
+    const { accepted, failed } = summarizePublishResults(results);
+    return {
+      ok: accepted.length > 0,
+      accepted: accepted.length,
+      total: accepted.length + failed.length,
+      event: signed,
+    };
+  }
+
+  return { isAvailable, canMirror, publish };
+}
+
+export const nip71MirrorService = createNip71MirrorService();
+
+export default nip71MirrorService;
diff --git a/tests/nip71-mirror-service.test.mjs b/tests/nip71-mirror-service.test.mjs
new file mode 100644
index 00000000..010cc242
--- /dev/null
+++ b/tests/nip71-mirror-service.test.mjs
@@ -0,0 +1,107 @@
+// Phase 1: the NIP-71 mirror publish service. Scenarios assert the observable
+// outcomes at the publish boundary, especially the site-wide NSFW moderation gate
+// (ALLOW_NSFW_CONTENT) — an instance that won't surface NSFW must not publish it
+// outward — plus the private / url / availability gates and a real publish.
+
+import "./test-helpers/setup-localstorage.mjs";
+import assert from "node:assert/strict";
+import test from "node:test";
+import { createNip71MirrorService } from "../js/services/nip71MirrorService.js";
+import {
+  publishEventToRelays,
+  summarizePublishResults,
+} from "../js/nostrPublish.js";
+
+const PUBKEY = "a".repeat(64);
+
+function baseVideo(overrides = {}) {
+  return {
+    videoRootId: "root-1",
+    pubkey: PUBKEY,
+    title: "Hello",
+    description: "desc",
+    url: "https://cdn.example.com/v.mp4",
+    thumbnail: "https://cdn.example.com/t.jpg",
+    isPrivate: false,
+    isNsfw: false,
+    ...overrides,
+  };
+}
+
+// Faithful relay twin: stores published events; thenable publish => success path.
+function makeRelay() {
+  const events = [];
+  return {
+    events,
+    publish(_urls, event) {
+      events.push(event);
+      return Promise.resolve();
+    },
+  };
+}
+
+function makeService({ allowNsfw = false, available = true } = {}) {
+  const relay = makeRelay();
+  const signer = available
+    ? { signEvent: async (tpl) => ({ ...tpl, id: "id", sig: "sig" }) }
+    : null;
+  const service = createNip71MirrorService({
+    getActivePubkey: () => (available ? PUBKEY : ""),
+    getSigner: () => signer,
+    getWriteRelays: () => ["wss://write.relay"],
+    getPool: () => relay,
+    publishEventToRelays,
+    summarizePublishResults,
+    signEvent: signer ? signer.signEvent : async () => { throw new Error("no signer"); },
+    allowNsfw: () => allowNsfw === true,
+  });
+  return { service, relay };
+}
+
+test("publishes a public video as an addressable 34235 mirror to the write relays", async () => {
+  const { service, relay } = makeService();
+  const result = await service.publish(baseVideo());
+  assert.equal(result.ok, true);
+  assert.equal(result.accepted, 1);
+  assert.equal(relay.events.length, 1);
+  assert.equal(relay.events[0].kind, 34235);
+  assert.equal(relay.events[0].tags.find((t) => t[0] === "d")[1], "root-1");
+});
+
+test("NSFW video is NOT mirrored when the instance forbids NSFW (ALLOW_NSFW_CONTENT=false)", async () => {
+  const { service, relay } = makeService({ allowNsfw: false });
+  const result = await service.publish(baseVideo({ isNsfw: true }));
+  assert.equal(result.ok, false);
+  assert.equal(result.reason, "nsfw-blocked");
+  assert.equal(relay.events.length, 0, "must not publish NSFW outward");
+  assert.deepEqual(service.canMirror(baseVideo({ isNsfw: true })), {
+    ok: false,
+    reason: "nsfw-blocked",
+  });
+});
+
+test("NSFW video IS mirrored when the instance allows NSFW", async () => {
+  const { service, relay } = makeService({ allowNsfw: true });
+  const result = await service.publish(baseVideo({ isNsfw: true, nsfwReason: "mature" }));
+  assert.equal(result.ok, true);
+  assert.equal(relay.events.length, 1);
+  assert.equal(
+    relay.events[0].tags.find((t) => t[0] === "content-warning")[1],
+    "mature",
+  );
+});
+
+test("private and url-less videos are refused (builder rules)", async () => {
+  const { service, relay } = makeService();
+  assert.equal((await service.publish(baseVideo({ isPrivate: true }))).reason, "private");
+  assert.equal((await service.publish(baseVideo({ url: "" }))).reason, "no-url");
+  assert.equal(relay.events.length, 0);
+});
+
+test("publish is unavailable without a signer / pubkey", async () => {
+  const { service } = makeService({ available: false });
+  assert.equal(service.isAvailable(), false);
+  const result = await service.publish(baseVideo());
+  assert.equal(result.ok, false);
+  assert.equal(result.error, "unavailable");
+});