diff --git a/server/tests/integration/test_practice_attempts.py b/server/tests/integration/test_practice_attempts.py
new file mode 100644
index 0000000..5c871cb
--- /dev/null
+++ b/server/tests/integration/test_practice_attempts.py
@@ -0,0 +1,90 @@
+"""独立 Attempt 链路：双读合并、并发 reserve 的 round 唯一性。"""
+
+from concurrent.futures import ThreadPoolExecutor
+from unittest.mock import AsyncMock, patch
+
+from pymongo import MongoClient
+
+from tests.conftest import TEST_DB_NAME
+
+CORRECT_RESULT = {"summary": "ok", "score": 6.0, "standardAnswer": "native", "gaps": [], "progress": None}
+
+
+def test_dual_read_merges_embedded_and_independent_by_round(client, user_id, auth_headers, practice_id):
+    """迁移过渡期：嵌入 round 1 + 独立 round 2 合并成完整列表，且都带稳定 attemptId。"""
+    mongo = MongoClient("mongodb://localhost:27017/")
+    db = mongo[TEST_DB_NAME]
+    db.practiceSessions.update_one(
+        {"_id": practice_id},
+        {"$push": {"attempts": {"round": 1, "transcript": "embedded take", "score": 5.0}}},
+    )
+    db.practiceAttempts.insert_one({
+        "_id": "pa_independent_round2",
+        "practiceId": practice_id,
+        "userId": user_id,
+        "round": 2,
+        "transcript": "independent take",
+        "score": 7.0,
+        "status": "completed",
+    })
+    mongo.close()
+
+    practice = client.get(f"/api/practice-sessions/{practice_id}", headers=auth_headers).json()
+    attempts = practice["attempts"]
+
+    assert [a["round"] for a in attempts] == [1, 2]
+    assert attempts[0]["transcript"] == "embedded take"
+    assert attempts[0]["attemptId"].startswith("pa_")
+    assert attempts[1]["attemptId"] == "pa_independent_round2"
+
+
+def test_dual_read_independent_row_wins_over_embedded_same_round(client, user_id, auth_headers, practice_id):
+    mongo = MongoClient("mongodb://localhost:27017/")
+    db = mongo[TEST_DB_NAME]
+    db.practiceSessions.update_one(
+        {"_id": practice_id},
+        {"$push": {"attempts": {"round": 1, "transcript": "stale embedded"}}},
+    )
+    db.practiceAttempts.insert_one({
+        "_id": "pa_winner",
+        "practiceId": practice_id,
+        "userId": user_id,
+        "round": 1,
+        "transcript": "fresh independent",
+        "status": "completed",
+    })
+    mongo.close()
+
+    practice = client.get(f"/api/practice-sessions/{practice_id}", headers=auth_headers).json()
+
+    assert len(practice["attempts"]) == 1
+    assert practice["attempts"][0]["transcript"] == "fresh independent"
+
+
+def test_concurrent_corrections_get_unique_rounds(client, user_id, auth_headers, practice_id):
+    """并发完成回调不产生重复 (practiceId, round)。"""
+    with patch("routes.correct.correct_text", new=AsyncMock(return_value=CORRECT_RESULT)):
+        with ThreadPoolExecutor(max_workers=3) as pool:
+            responses = list(pool.map(
+                lambda i: client.post(
+                    "/api/correct",
+                    json={
+                        "userId": user_id,
+                        "practiceId": practice_id,
+                        "text": f"concurrent take {i}",
+                    },
+                    headers=auth_headers,
+                ),
+                range(3),
+            ))
+
+    bodies = [r.json() for r in responses]
+    assert all(r.status_code == 200 for r in responses)
+    assert sorted(b["round"] for b in bodies) == [1, 2, 3]
+    assert len({b["attemptId"] for b in bodies}) == 3
+
+    mongo = MongoClient("mongodb://localhost:27017/")
+    docs = list(mongo[TEST_DB_NAME].practiceAttempts.find({"practiceId": practice_id}))
+    mongo.close()
+    pairs = [(d["practiceId"], d["round"]) for d in docs]
+    assert len(pairs) == len(set(pairs)) == 3
diff --git a/server/tests/integration/test_practice_sessions.py b/server/tests/integration/test_practice_sessions.py
index 671edf6..c78d6a9 100644
--- a/server/tests/integration/test_practice_sessions.py
+++ b/server/tests/integration/test_practice_sessions.py
@@ -383,3 +383,42 @@ def test_create_practice_rejects_userid_token_mismatch(client, user_id, auth_hea
         headers=auth_headers,
     )
     assert resp.status_code == 403
+
+
+def test_upload_recording_replaces_previous_object(
+    client, user_id, auth_headers, practice_id, monkeypatch,
+):
+    """同一 attempt 二次上传录音时，旧 OSS 对象要被登记删除。"""
+    from unittest.mock import AsyncMock, MagicMock
+    monkeypatch.setattr("routes.practice_sessions.upload_bytes_async", AsyncMock(return_value=None))
+    monkeypatch.setattr("routes.practice_sessions.oss_signed_url", MagicMock(return_value="https://signed"))
+    deleted = []
+
+    async def _record_delete(key):
+        deleted.append(key)
+
+    monkeypatch.setattr("routes.practice_sessions.delete_async", _record_delete)
+    mongo = MongoClient("mongodb://localhost:27017/")
+    mongo[TEST_DB_NAME].practiceSessions.update_one(
+        {"_id": practice_id}, {"$push": {"attempts": {"round": 1}}}
+    )
+    mongo.close()
+
+    def upload(tag: bytes) -> dict:
+        resp = client.post(
+            f"/api/practice-sessions/{practice_id}/recording",
+            data={"userId": user_id, "attemptIndex": 0},
+            files={"audio": ("r.webm", tag, "audio/webm")},
+            headers=auth_headers,
+        )
+        assert resp.status_code == 200
+        return resp.json()
+
+    first = upload(b"FIRST_TAKE")
+    second = upload(b"SECOND_TAKE")
+
+    first_key = first["recording"]["key"]
+    assert deleted == [first_key]
+    assert second["recording"]["key"] != first_key
+    p = client.get(f"/api/practice-sessions/{practice_id}", headers=auth_headers).json()
+    assert p["attempts"][0]["recording"]["key"] == second["recording"]["key"]
diff --git a/server/tests/integration/test_tts.py b/server/tests/integration/test_tts.py
index c72bbfe..4986551 100644
--- a/server/tests/integration/test_tts.py
+++ b/server/tests/integration/test_tts.py
@@ -83,3 +83,49 @@ def test_tts_rejects_missing_token(client):
         resp = client.post("/api/tts", json={"text": "Hi"})
     assert resp.status_code == 401
     fake.assert_not_called()
+
+
+def test_tts_unknown_practice_404(client, auth_headers):
+    resp = client.post(
+        "/api/tts",
+        json={"text": "Hi", "practiceId": "ps_does_not_exist"},
+        headers=auth_headers,
+    )
+    assert resp.status_code == 404
+
+
+def test_tts_without_any_attempt_409(client, auth_headers, practice_id):
+    resp = client.post(
+        "/api/tts",
+        json={"text": "Hi", "practiceId": practice_id},
+        headers=auth_headers,
+    )
+    assert resp.status_code == 409
+
+
+def test_tts_archives_into_legacy_embedded_attempt(client, auth_headers, practice_id):
+    """独立 Attempt 不存在时，speechAssets 回退写嵌入数组。"""
+    mongo = MongoClient("mongodb://localhost:27017/")
+    mongo[TEST_DB_NAME].practiceSessions.update_one(
+        {"_id": practice_id}, {"$push": {"attempts": {"round": 1}}}
+    )
+    mongo.close()
+    fake = AsyncMock(return_value="https://oss.example/speech.wav?sig=x")
+    with patch("routes.tts.speak_url", new=fake):
+        resp = client.post(
+            "/api/tts",
+            json={
+                "text": "Could you remake my latte?",
+                "practiceId": practice_id,
+                "purpose": "standard-answer",
+            },
+            headers=auth_headers,
+        )
+    assert resp.status_code == 200
+    mongo = MongoClient("mongodb://localhost:27017/")
+    practice = mongo[TEST_DB_NAME].practiceSessions.find_one({"_id": practice_id})
+    mongo.close()
+    assets = practice["attempts"][0]["speechAssets"]
+    assert len(assets) == 1
+    assert assets[0]["purpose"] == "standard-answer"
+    assert "/attempts/pa_" in assets[0]["key"]
diff --git a/server/tests/unit/test_storage_paths.py b/server/tests/unit/test_storage_paths.py
index 1f6dc36..b979d84 100644
--- a/server/tests/unit/test_storage_paths.py
+++ b/server/tests/unit/test_storage_paths.py
@@ -63,3 +63,39 @@ def test_attempt_path_requires_stable_attempt_id():
             "rec_1",
             "webm",
         )
+
+
+@pytest.mark.parametrize("created_at", [
+    "2026-08-13 17:24:36.826000",
+    "2026-08-13T17:24:36+00:00",
+    "20260813172436",
+])
+def test_month_accepts_string_created_at(created_at):
+    key = recording_original_key(
+        PracticeAssetContext("u_1", created_at, "ps_1", "pa_1"), "rec_1", "webm",
+    )
+
+    assert "/202608/" in key
+
+
+@pytest.mark.parametrize("created_at", ["", "2026", "abcdefgh", None])
+def test_month_rejects_values_without_year_month(created_at):
+    with pytest.raises(ValueError, match="year and month"):
+        recording_original_key(
+            PracticeAssetContext("u_1", created_at, "ps_1", "pa_1"), "rec_1", "webm",
+        )
+
+
+def test_speech_path_rejects_unknown_purpose():
+    with pytest.raises(ValueError, match="purpose"):
+        speech_key(CONTEXT, "karaoke", "tts_a", "wav")
+
+
+def test_avatar_key_rejects_unknown_variant():
+    with pytest.raises(ValueError, match="variant"):
+        avatar_key("u_1", "av_1", "medium")
+
+
+def test_feedback_image_rejects_unknown_extension():
+    with pytest.raises(ValueError, match="extension"):
+        feedback_image_key("u_1", CREATED_AT, "fb_1", "fi_1", "exe")
diff --git a/web/e2e/journey.spec.js b/web/e2e/journey.spec.js
new file mode 100644
index 0000000..36484af
--- /dev/null
+++ b/web/e2e/journey.spec.js
@@ -0,0 +1,145 @@
+import { expect, test } from "@playwright/test";
+
+// 无后端链路冒烟：mock /api/**，覆盖登录→派题、结果页 ?attempt= 还原与切换、
+// 历史→详情、分享页精确轮次。多引擎/多视口下跑，防页面级回归。
+const USER = {
+  userId: "u_journey",
+  phone: "13800000000",
+  nickname: "journey",
+  sourceType: "ai_test",
+  token: "tok_journey",
+};
+
+const SCENARIO_NEXT = {
+  scenarioId: "sc_journey",
+  kind: "task",
+  title: "咖啡店重做饮品",
+  where: "咖啡店 · 西雅图",
+  story: "店员把你的热拿铁做成了冰拿铁。",
+  mission: "礼貌说明问题，请店员重做。",
+  points: ["说明饮品做错了"],
+  imageUrl: "",
+  videoUrl: "",
+  isCustom: false,
+  preferenceMatch: "fallback",
+  targetWords: [],
+};
+
+const SESSION = {
+  _id: "sess_journey",
+  userId: USER.userId,
+  scenarioId: "sc_journey",
+  title: "咖啡店重做饮品",
+  topic: "咖啡店 · 西雅图",
+  mode: "scenario",
+  scenario: {
+    title: "拿错了饮品",
+    where: "咖啡店 · 西雅图",
+    story: "店员把你的热拿铁做成了冰拿铁。",
+    mission: "礼貌说明问题，请店员重做。",
+    points: ["说明饮品做错了"],
+  },
+  attempts: [
+    {
+      attemptId: "pa_j1", round: 1, transcript: "first round",
+      summary: "ROUND_ONE_SUMMARY", score: 5.0, gaps: [], standardAnswer: "SA_ONE", standardAnswerNotes: [],
+    },
+    {
+      attemptId: "pa_j2", round: 2, transcript: "second round",
+      summary: "ROUND_TWO_SUMMARY", score: 7.0, gaps: [], standardAnswer: "SA_TWO", standardAnswerNotes: [],
+    },
+  ],
+};
+
+async function setup(page, { loggedIn = true } = {}) {
+  await page.route("https://fonts.googleapis.com/**", (route) => route.fulfill({
+    body: "",
+    contentType: "text/css",
+  }));
+  await page.route("https://fonts.gstatic.com/**", (route) => route.abort());
+  if (loggedIn) {
+    await page.addInitScript((user) => {
+      localStorage.setItem("english-speak-user", JSON.stringify(user));
+      localStorage.setItem("speakup_lang", "en");
+      localStorage.setItem(
+        `speakup-practice-preferences:${user.userId}`,
+        JSON.stringify({ level: "daily", purpose: "travel" }),
+      );
+    }, USER);
+  }
+  await page.route("**/api/**", (route) => {
+    const { pathname } = new URL(route.request().url());
+    const method = route.request().method();
+    if (method === "POST" && pathname === "/api/auth/login") {
+      return route.fulfill({ json: USER });
+    }
+    if (pathname === "/api/scenarios/next") {
+      return route.fulfill({ json: SCENARIO_NEXT });
+    }
+    if (pathname === "/api/practice-sessions" && method === "GET") {
+      return route.fulfill({ json: [SESSION] });
+    }
+    if (pathname === "/api/practice-sessions" && method === "POST") {
+      return route.fulfill({ json: SESSION });
+    }
+    if (pathname === "/api/practice-sessions/sess_journey") {
+      return route.fulfill({ json: SESSION });
+    }
+    if (pathname === "/api/share/tok_journey") {
+      return route.fulfill({ json: { ...SESSION, ownerNickname: USER.nickname, shared: true } });
+    }
+    if (pathname === "/api/feedbacks") {
+      return route.fulfill({ json: [] });
+    }
+    return route.fulfill({ json: {} });
+  });
+}
+
+test("登录成功后选题开始并渲染场景", async ({ page }) => {
+  await setup(page, { loggedIn: false });
+  await page.goto("/", { waitUntil: "domcontentloaded" });
+
+  await page.locator("input[type='tel']").fill("13800001234");
+  await page.locator("button").click();
+
+  await expect(page).toHaveURL(/\/practice$/);
+  await page.getByRole("button", { name: "Start practicing" }).click();
+
+  await expect(page).toHaveURL(/\/practice\/sess_journey/);
+  await expect(page.getByText("店员把你的热拿铁做成了冰拿铁。").first()).toBeVisible();
+});
+
+test("结果页 attempt 参数精确还原对应轮次", async ({ page }) => {
+  await setup(page);
+  await page.goto("/practice/sess_journey?attempt=pa_j2", { waitUntil: "domcontentloaded" });
+
+  await expect(page.getByText("ROUND_TWO_SUMMARY")).toBeVisible();
+  await expect(page.getByText("Attempt #2")).toBeVisible();
+
+  await page.goto("/practice/sess_journey?attempt=pa_j1", { waitUntil: "domcontentloaded" });
+  await expect(page.getByText("ROUND_ONE_SUMMARY")).toBeVisible();
+  await expect(page.getByText("Attempt #1")).toBeVisible();
+});
+
+test("历史列表进入会话详情", async ({ page }) => {
+  await setup(page);
+  await page.goto("/history", { waitUntil: "domcontentloaded" });
+
+  await expect(page.getByText("咖啡店重做饮品").first()).toBeVisible();
+  await page.locator(".history-headline").first().click();
+
+  await expect(page).toHaveURL(/\/history\/sess_journey/);
+  await expect(page.locator(".attempt-tab")).toHaveCount(2);
+  await expect(page.getByText("ROUND_TWO_SUMMARY")).toBeVisible();
+
+  await page.locator(".attempt-tab").first().click();
+  await expect(page.getByText("ROUND_ONE_SUMMARY")).toBeVisible();
+});
+
+test("分享页按 attempt 参数打开被分享轮次", async ({ page }) => {
+  await setup(page, { loggedIn: false });
+  await page.goto("/s/tok_journey?attempt=pa_j1", { waitUntil: "domcontentloaded" });
+
+  await expect(page.getByText("ROUND_ONE_SUMMARY")).toBeVisible();
+  await expect(page.locator(".attempt-tab.active")).toHaveText("Attempt 1");
+});