diff --git a/.github/workflows/app-ci.yml b/.github/workflows/app-ci.yml
index 4934de58c..08167eea8 100644
--- a/.github/workflows/app-ci.yml
+++ b/.github/workflows/app-ci.yml
@@ -24,6 +24,24 @@ jobs:
     env:
       PYTHONWARNINGS: error
       DISABLE_BACKGROUND_WORKERS: "1"
+      DATABASE_URL: postgresql+asyncpg://test:test@localhost:5432/test_db
+    services:
+      postgres:
+        # Bundles the pgvector extension so backend/scripts/bootstrap_db.py's
+        # `CREATE EXTENSION IF NOT EXISTS vector` needs no separate install
+        # step; matches the blessed local stack in docker-compose.yml.
+        image: pgvector/pgvector:pg16@sha256:ccc6e83d6e35e931dc7c5def2022729d5a6c370318d099181995567ff1fb4d6b
+        env:
+          POSTGRES_USER: test
+          POSTGRES_PASSWORD: test
+          POSTGRES_DB: test_db
+        ports:
+          - 5432:5432
+        options: >-
+          --health-cmd="pg_isready -U test -d test_db"
+          --health-interval=5s
+          --health-timeout=5s
+          --health-retries=10
     steps:
       - name: Harden the runner (Audit all outbound calls)
         uses: step-security/harden-runner@bf7454d06d71f1098171f2acdf0cd4708d7b5920 # v2.20.0
diff --git a/AGENTS.md b/AGENTS.md
index 9104dd1f4..e934d7e8f 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -623,6 +623,13 @@ in this repo.
   (`created_at`, `observed_at`, `parse_content_type`, `parser_key`). Under
   asyncpg, `INSERT ... SELECT`/`UNION` parameters default to `text`, so cast
   integer FK params explicitly (`CAST(:email_id AS INTEGER)`).
+- The `backend` CI job runs these real-Postgres tests against an actual
+  `pgvector/pgvector:pg16` `services:` container (`.github/workflows/app-ci.yml`),
+  not a soft-skip: a broken seeding helper or migration now fails the job
+  instead of silently `pytest.skip`ping with "PostgreSQL smoke database/path
+  unavailable". Reproduce locally with any Postgres 16 + pgvector instance
+  (the `docker-compose.yml` `db` service works) before assuming a change is
+  green.
 - Postgres smoke seeding of `EncryptedString` columns
   (`credentials_encrypted`, provider `api_key`, runner tokens) must set a
   Fernet `ENCRYPTION_KEY` for the test (monkeypatch `settings.ENCRYPTION_KEY`)
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7ec84c36f..d648725a8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,26 @@
 ## [Unreleased]
+- **(CI 인프라, 🔴 critical) `backend` job에 Postgres 서비스 컨테이너가 없어 `@pytest.mark.postgres`
+  real-Postgres 테스트가 CI에서 단 한 번도 실제로 실행되지 않고 항상 조용히 skip되던 문제를
+  고쳤습니다.** `.github/workflows/app-ci.yml`의 `backend` job에 `pgvector/pgvector:pg16`
+  서비스 컨테이너(`test`/`test`/`test_db`, `pg_isready` 헬스체크)를 추가하고 `DATABASE_URL`을
+  같은 자격증명으로 설정해, `tests/conftest.py`의 기본값과 그대로 맞물리도록 했습니다. 실제로
+  CI 환경과 동일하게(로컬 PostgreSQL 16 + pgvector) 처음 돌려보자, 완전히 새 데이터베이스에 대한
+  `alembic upgrade head`가 `0011_email_read_state`에서 레거시 `emails` 테이블을 직접 대상으로
+  해 `relation "emails" does not exist`로 깨지는 결함과, `tests/test_bootstrap_db.py`/
+  `tests/test_data_api.py`의 raw SQL `INSERT INTO email_records`가 `is_read`(ORM 쪽
+  Python-side `default=True`뿐, DB 서버측 default 없음)를 빠뜨려 real Postgres에서
+  `NotNullViolationError`로 하드 실패하는 결함이 함께 드러났습니다. `#1503`이 동일한 근본
+  원인을 독립적으로 재현·수정(현재 `email_records`/레거시 `emails` 양쪽을 컬럼 존재 여부로
+  가드)했기에, 서로 다른 두 구현이 충돌하지 않도록 `0011_email_read_state.py`와
+  `backend/scripts/bootstrap_db.py`는 `#1503`의 구현으로 수렴시켰습니다 — 이 PR은 CI
+  service-container 추가와 그것이 처음으로 드러낸 `is_read` raw-SQL 시딩 결함 수정만
+  담당하는 의존성 루트 슬라이스로 범위를 좁혔습니다(owner 요청, 2026-09-02). PR-governance/
+  stacked-PR 트리거 관련 무관한 변경은 `#1531`로 분리했습니다.
+  전체 백엔드 스위트를 실제 PostgreSQL 16(+pgvector)로 검증: **1837 passed, 2 skipped**
+  (남은 2개는 `LIVE_BASE_URL` 미설정에 따른 무관한 live-API smoke skip), `ruff check` clean.
+  `CLAUDE.md`/`AGENTS.md`에 이 job이 이제 real-Postgres 테스트를 하드 게이트로 실행한다는 것과
+  로컬 재현 방법을 기록. 후속 과제로 남겨두었던 항목(`docs/product-technical-gap-baseline.md`,
+  `.github` repo)을 닫습니다.
 - 긴 이메일·첨부 본문을 의미 단위 청크로 임베딩한 뒤 기존 email/attachment 벡터 계약으로 평균화하고, 청크 요청·벡터 누적을 제한된 창으로 처리합니다. OpenAI `text-embedding-3-*`에는 저장 차원(`1536`)을 직접 요청하도록 보강했습니다. 합성 메일 fixture 5건(70청크)과 provider 요청 계약으로 1,536차원 벡터 경로를 검증했으며, 실행 시 선택한 임베딩 제공자에 본문·파싱된 첨부 텍스트를 전송할 수 있습니다. 회사 기밀 데이터는 fixture·commit·PR·log에 포함하지 않습니다.
 - EmailDetail 테스트가 지원하지 않는 스레드 병합/분리 버튼을 `textContent`뿐 아니라 `aria-label`과 `title` 접근 가능 이름으로도 검출하도록 바꿔, 아이콘 전용 버튼 회귀를 놓치지 않습니다.
 
diff --git a/CLAUDE.md b/CLAUDE.md
index be67bc80c..6ade80507 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -36,6 +36,13 @@ uvicorn main:app --reload                    # local dev server only
   `DISABLE_BACKGROUND_WORKERS=1`, then fails the job if the pytest output
   contains `Timeout`, `Fatal`, `Warn`, or `Denied`. Match that locally for
   merge evidence.
+- The `backend` job provisions a real `pgvector/pgvector:pg16` Postgres
+  `services:` container (`.github/workflows/app-ci.yml`), so every
+  `@pytest.mark.postgres`/real-Postgres smoke test actually runs in CI — it
+  is a hard gate, not a soft-skip. Locally, point `DATABASE_URL` at a
+  Postgres+pgvector instance (`docker-compose.yml`'s `db` service, or any
+  local Postgres 16) before running the full suite, or those tests skip with
+  `PostgreSQL smoke database/path unavailable` instead of proving anything.
 - Containers never run `uvicorn main:app` directly; the entrypoint is
   `python scripts/start_backend.py`, which validates required settings first.
 - `scripts/bootstrap_db.py` is the local/dev-only schema compatibility path;
diff --git a/backend/alembic/versions/0001_initial_control_plane.py b/backend/alembic/versions/0001_initial_control_plane.py
index cc14ce39b..31b187f55 100644
--- a/backend/alembic/versions/0001_initial_control_plane.py
+++ b/backend/alembic/versions/0001_initial_control_plane.py
@@ -9,7 +9,7 @@
 from sqlalchemy import text
 
 from db.models import Base
-from scripts.bootstrap_db import schema_backfill_sql
+from scripts.bootstrap_db import execute_schema_backfill
 
 revision = "0001_initial_control_plane"
 down_revision = None
@@ -19,8 +19,7 @@ def upgrade() -> None:
     connection = op.get_bind()
     connection.execute(text("CREATE EXTENSION IF NOT EXISTS vector"))
     Base.metadata.create_all(connection)
-    for statement in schema_backfill_sql():
-        connection.execute(statement)
+    execute_schema_backfill(connection)
 
 
 def downgrade() -> None:
diff --git a/backend/alembic/versions/0011_email_read_state.py b/backend/alembic/versions/0011_email_read_state.py
index 716590cd1..04fa068ce 100644
--- a/backend/alembic/versions/0011_email_read_state.py
+++ b/backend/alembic/versions/0011_email_read_state.py
@@ -1,6 +1,14 @@
-"""Add is_read to emails (IMAP \\Seen read state).
+"""Add is_read to email_records (IMAP \\Seen read state).
 
 Existing rows default to read so historical/file imports do not surface as unread.
+
+Checks both "email_records" (the real, current table -- a database whose own
+0001_initial_control_plane ran before ``is_read`` was added to the ``Email``
+model has this table without the column, and needs it added) and "emails"
+(a legacy name that, per 0011_email_model_reconciliation's docstring, no
+migration in this repo's history ever actually created for a real managed
+database, but is checked defensively in case one somehow exists). Guarded by
+column existence, not just table existence, so it is safely idempotent.
 """
 
 from alembic import op
@@ -12,18 +20,40 @@
 branch_labels = None
 depends_on = None
 
+_CANDIDATE_TABLES = ("email_records", "emails")
+
 
 def upgrade() -> None:
-    op.add_column(
-        "emails",
-        sa.Column(
-            "is_read",
-            sa.Boolean(),
-            nullable=False,
-            server_default=sa.text("true"),
-        ),
-    )
+    inspector = sa.inspect(op.get_bind())
+    for table_name in _CANDIDATE_TABLES:
+        if inspector.has_table(table_name) and not _has_column(
+            inspector, table_name, "is_read"
+        ):
+            op.add_column(
+                table_name,
+                sa.Column(
+                    "is_read",
+                    sa.Boolean(),
+                    nullable=False,
+                    server_default=sa.text("true"),
+                ),
+            )
 
 
 def downgrade() -> None:
-    op.drop_column("emails", "is_read")
+    # Same ownership-ambiguity problem as 0018_workspace_registry's downgrade:
+    # a fresh database gets email_records.is_read from 0001's live
+    # Base.metadata.create_all, not from this revision, so there is no way to
+    # tell "this revision added the column" apart from "the baseline already
+    # had it" -- and is_read holds real per-message read/unread state, not
+    # rebuildable derived data. As with 0001_initial_control_plane and
+    # 0018_workspace_registry: production rollbacks should restore from
+    # backup or a later explicit down revision rather than dropping
+    # customer-owned data.
+    return None
+
+
+def _has_column(inspector, table_name: str, column_name: str) -> bool:
+    return any(
+        column["name"] == column_name for column in inspector.get_columns(table_name)
+    )
diff --git a/backend/scripts/bootstrap_db.py b/backend/scripts/bootstrap_db.py
index 1047103e8..3a1211181 100644
--- a/backend/scripts/bootstrap_db.py
+++ b/backend/scripts/bootstrap_db.py
@@ -1,16 +1,12 @@
 import asyncio
 import os
-from collections.abc import Sequence
-
-from sqlalchemy import Executable, text
+from sqlalchemy import Executable, Index, MetaData, Table, inspect, text
 from sqlalchemy.engine import Connection
 
 from db.models import Base
 from db.session import engine
 
 INVALID_EMAIL_BACKFILL_OWNER_IDS = {None, "", "default"}
-
-
 def _static_bootstrap_sql(statement: str) -> Executable:
     # ponytail: repo-authored static bootstrap SQL only; bind params before runtime input.
     return text(statement)
@@ -186,10 +182,6 @@ def _get_create_indexes_statements() -> list[Executable]:
             "CREATE INDEX IF NOT EXISTS ix_email_records_owner_date "
             "ON email_records (user_id, organization_id, date)"
         ),
-        text(
-            "CREATE INDEX IF NOT EXISTS ix_emails_owner_date "
-            "ON emails (user_id, organization_id, date)"
-        ),
         text(
             "CREATE INDEX IF NOT EXISTS ix_sender_relationships_owner_source "
             "ON sender_relationships "
@@ -527,16 +519,24 @@ def schema_backfill_sql() -> list[Executable]:
     return statements
 
 
-def _execute_statements(conn: Connection, statements: Sequence[Executable]) -> None:
-    for statement in statements:
+def execute_schema_backfill(conn: Connection) -> None:
+    for statement in schema_backfill_sql():
         conn.execute(statement)
+    if inspect(conn).has_table("emails"):
+        emails = Table("emails", MetaData(), autoload_with=conn)
+        Index(
+            "ix_emails_owner_date",
+            emails.c.user_id,
+            emails.c.organization_id,
+            emails.c.date,
+        ).create(conn, checkfirst=True)
 
 
 async def bootstrap_db() -> None:
     async with engine.begin() as conn:
         await conn.execute(text("CREATE EXTENSION IF NOT EXISTS vector"))
         await conn.run_sync(Base.metadata.create_all)
-        await conn.run_sync(_execute_statements, schema_backfill_sql())
+        await conn.run_sync(execute_schema_backfill)
 
 
 if __name__ == "__main__":
diff --git a/backend/tests/test_alembic_migrations.py b/backend/tests/test_alembic_migrations.py
index f8f3ffeae..0045cab10 100644
--- a/backend/tests/test_alembic_migrations.py
+++ b/backend/tests/test_alembic_migrations.py
@@ -32,7 +32,32 @@ def test_initial_alembic_revision_records_current_schema_path():
     assert "down_revision = None" in revision_text
     assert "CREATE EXTENSION IF NOT EXISTS vector" in revision_text
     assert "Base.metadata.create_all" in revision_text
-    assert "schema_backfill_sql" in revision_text
+    assert "execute_schema_backfill" in revision_text
+
+
+def test_email_read_state_guards_both_legacy_and_current_table_names():
+    """0011_email_read_state must add is_read to a genuinely historical
+    email_records table missing it (a database whose own 0001 ran before
+    is_read was added to the Email model), not just a legacy "emails" table
+    that, per 0011_email_model_reconciliation's docstring, no migration in
+    this repo's history ever actually created for a real managed database.
+    The upgrade check must guard on column existence, not just table
+    existence, so it stays idempotent against a table that already has the
+    column. downgrade is a no-op: a fresh database's email_records.is_read
+    comes from 0001's live create_all, not from this revision, so there is
+    no way to tell "this revision added it" apart from "the baseline already
+    had it" -- and is_read holds real read/unread state, not rebuildable
+    derived data (same ownership-ambiguity reasoning as
+    0018_workspace_registry's downgrade)."""
+    revision_path = BACKEND_ROOT / "alembic" / "versions" / "0011_email_read_state.py"
+    revision_text = revision_path.read_text()
+
+    assert '"email_records"' in revision_text
+    assert '"emails"' in revision_text
+    assert "has_table" in revision_text
+    assert "_has_column" in revision_text
+    assert "op.add_column(" in revision_text
+    assert "op.drop_column(" not in revision_text
 
 
 def test_provider_writeback_retry_queue_has_incremental_revision():
diff --git a/backend/tests/test_bootstrap_db.py b/backend/tests/test_bootstrap_db.py
index 5af0540f0..95a4e72d9 100644
--- a/backend/tests/test_bootstrap_db.py
+++ b/backend/tests/test_bootstrap_db.py
@@ -6,7 +6,7 @@
 
 from core.config import settings
 from db.models import Base
-from scripts.bootstrap_db import schema_backfill_sql
+from scripts.bootstrap_db import execute_schema_backfill, schema_backfill_sql
 from db.models import (
     AgentRunRecord,
     CalendarWritebackSource,
@@ -30,8 +30,7 @@ def _get_schema_statements(monkeypatch):
 
 
 def _execute_schema_backfill(sync_conn):
-    for statement in schema_backfill_sql():
-        sync_conn.execute(statement)
+    execute_schema_backfill(sync_conn)
 
 
 def test_schema_backfill_adds_email_columns(monkeypatch):
@@ -770,11 +769,11 @@ async def test_connector_signal_events_real_postgres_bootstrap_smoke():
                 text("""
                     INSERT INTO email_records (
                         user_id, organization_id, message_id, sender, recipients,
-                        subject, "date", body
+                        subject, "date", body, is_read
                     )
                     VALUES (
                         :user_id, :organization_id, :message_id, :sender,
-                        :recipients, :subject, now(), :body
+                        :recipients, :subject, now(), :body, true
                     )
                     RETURNING id
                     """),
diff --git a/backend/tests/test_data_api.py b/backend/tests/test_data_api.py
index cd0b7bf37..c47005ca1 100644
--- a/backend/tests/test_data_api.py
+++ b/backend/tests/test_data_api.py
@@ -2951,11 +2951,11 @@ async def _seed_smoke_test_data(conn, ids: dict):
             """
             INSERT INTO email_records (
                 user_id, organization_id, message_id, thread_id,
-                fingerprint, sender, recipients, subject, "date", body
+                fingerprint, sender, recipients, subject, "date", body, is_read
             )
             VALUES (
                 :user_id, :organization_id, :message_id, :thread_id,
-                :fingerprint, :sender, :recipients, :subject, now(), :body
+                :fingerprint, :sender, :recipients, :subject, now(), :body, true
             )
             RETURNING id
             """
@@ -2977,11 +2977,11 @@ async def _seed_smoke_test_data(conn, ids: dict):
             """
             INSERT INTO email_records (
                 user_id, organization_id, message_id, sender, recipients,
-                subject, "date", body
+                subject, "date", body, is_read
             )
             VALUES (
                 :user_id, :organization_id, :message_id, :sender,
-                :recipients, :subject, now(), :body
+                :recipients, :subject, now(), :body, true
             )
             RETURNING id
             """
@@ -3001,11 +3001,11 @@ async def _seed_smoke_test_data(conn, ids: dict):
             """
             INSERT INTO email_records (
                 user_id, organization_id, message_id, thread_id,
-                fingerprint, sender, recipients, subject, "date", body
+                fingerprint, sender, recipients, subject, "date", body, is_read
             )
             VALUES (
                 :user_id, :organization_id, :message_id, :thread_id,
-                :fingerprint, :sender, :recipients, :subject, now(), :body
+                :fingerprint, :sender, :recipients, :subject, now(), :body, true
             )
             RETURNING id
             """
diff --git a/backend/tests/test_release_governance.py b/backend/tests/test_release_governance.py
index 394b1e39f..01a43b19b 100644
--- a/backend/tests/test_release_governance.py
+++ b/backend/tests/test_release_governance.py
@@ -663,6 +663,11 @@ def test_app_ci_runs_backend_and_frontend_checks_without_duplicate_release_pushe
     assert "uses: actions/checkout@v" not in workflow
     assert "uses: actions/setup-python@v" not in workflow
     assert "uses: actions/setup-node@v" not in workflow
+    assert (
+        "image: pgvector/pgvector:pg16@sha256:"
+        "ccc6e83d6e35e931dc7c5def2022729d5a6c370318d099181995567ff1fb4d6b"
+        in workflow
+    )
 
     push_block = workflow.split("push:", 1)[1].split("pull_request:", 1)[0]
     assert "master" in push_block