diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index c90e54e..4823457 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -1,5 +1,19 @@
 # NestQuest Release Notes
 
+## Unreleased
+
+- **Storage layer extraction (task d0b691d8):** the SQLite storage layer
+  (schema, migrations, db, store, const, recurrence, DAOs) is bundled
+  under `custom_components/nestquest/core/`, with the integration's
+  original module names preserved as re-export shims.
+- **Logger namespace change (breaking for logging configuration):** the
+  migrations runner now logs under
+  `custom_components.nestquest.core.migrations` instead of
+  `custom_components.nestquest.migrations`. Users who tuned the old
+  logger name (e.g. in `logger.yaml` or `configuration.yaml`) must
+  update the entry to keep that level, as the old name no longer
+  receives migration log output.
+
 ## Version 0.5.0 — 2026-09-18
 
 ### Scope
diff --git a/custom_components/nestquest/const.py b/custom_components/nestquest/const.py
index 4edc3ee..5b97150 100644
--- a/custom_components/nestquest/const.py
+++ b/custom_components/nestquest/const.py
@@ -1,6 +1,6 @@
-"""Re-export of :mod:`core.const` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.const` for the integration package.
 
-The canonical constants live in :mod:`core.const` (the storage layer
+The canonical constants live in :mod:`custom_components.nestquest.core.const` (the storage layer
 extracted in task d0b691d8); this module re-exports them so existing
 ``from .const import ...`` references inside the integration keep
 working without touching every import line.
diff --git a/custom_components/nestquest/core/__init__.py b/custom_components/nestquest/core/__init__.py
index 1903490..89e132f 100644
--- a/custom_components/nestquest/core/__init__.py
+++ b/custom_components/nestquest/core/__init__.py
@@ -5,7 +5,7 @@ SQLite storage layer: schema DDL, the versioned migration runner, the
 async connection wrapper, the path resolver, the domain constants and
 recurrence model, and the typed DAOs.  Nothing in this package imports
 ``homeassistant``; the integration wires it into HA at its own layer
-(constructing :class:`core.db.NestQuestDatabase` with an executor
-adapter backed by ``hass.async_add_executor_job``).
+(constructing :class:`custom_components.nestquest.core.db.NestQuestDatabase`
+with an executor adapter backed by ``hass.async_add_executor_job``).
 """
 from __future__ import annotations
diff --git a/custom_components/nestquest/dao_children.py b/custom_components/nestquest/dao_children.py
index 6e37e39..6ee1e2e 100644
--- a/custom_components/nestquest/dao_children.py
+++ b/custom_components/nestquest/dao_children.py
@@ -1,6 +1,7 @@
-"""Re-export of :mod:`core.dao_children` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.dao_children` for the integration package.
 
-The children/admin DAO lives in :mod:`core.dao_children` (extracted in
+The children/admin DAO lives in
+:mod:`custom_components.nestquest.core.dao_children` (extracted in
 task d0b691d8); this module re-exports it so existing
 ``from .dao_children import ...`` references inside the integration keep
 working.
diff --git a/custom_components/nestquest/dao_instances.py b/custom_components/nestquest/dao_instances.py
index 65f67d5..1ac0c9e 100644
--- a/custom_components/nestquest/dao_instances.py
+++ b/custom_components/nestquest/dao_instances.py
@@ -1,6 +1,7 @@
-"""Re-export of :mod:`core.dao_instances` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.dao_instances` for the integration package.
 
-The instances/completion-events DAO lives in :mod:`core.dao_instances`
+The instances/completion-events DAO lives in
+:mod:`custom_components.nestquest.core.dao_instances`
 (extracted in task d0b691d8); this module re-exports it so existing
 ``from .dao_instances import ...`` references inside the integration keep
 working.
diff --git a/custom_components/nestquest/dao_meta.py b/custom_components/nestquest/dao_meta.py
index a4275c5..bef9c16 100644
--- a/custom_components/nestquest/dao_meta.py
+++ b/custom_components/nestquest/dao_meta.py
@@ -1,6 +1,7 @@
-"""Re-export of :mod:`core.dao_meta` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.dao_meta` for the integration package.
 
-The meta-state DAO lives in :mod:`core.dao_meta` (extracted in task
+The meta-state DAO lives in
+:mod:`custom_components.nestquest.core.dao_meta` (extracted in task
 d0b691d8); this module re-exports it so existing
 ``from .dao_meta import ...`` references inside the integration keep
 working.
diff --git a/custom_components/nestquest/dao_presence.py b/custom_components/nestquest/dao_presence.py
index 8dab0bd..422ae17 100644
--- a/custom_components/nestquest/dao_presence.py
+++ b/custom_components/nestquest/dao_presence.py
@@ -1,7 +1,8 @@
-"""Re-export of :mod:`core.dao_presence` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.dao_presence` for the integration package.
 
-The presence DAOs live in :mod:`core.dao_presence` (extracted in task
-d0b691d8); this module re-exports them so existing
+The presence DAOs live in
+:mod:`custom_components.nestquest.core.dao_presence` (extracted in
+task d0b691d8); this module re-exports them so existing
 ``from .dao_presence import ...`` references inside the integration keep
 working.
 """
diff --git a/custom_components/nestquest/dao_rules.py b/custom_components/nestquest/dao_rules.py
index 85ec4d9..31c4ab9 100644
--- a/custom_components/nestquest/dao_rules.py
+++ b/custom_components/nestquest/dao_rules.py
@@ -1,9 +1,10 @@
-"""Re-export of :mod:`core.dao_rules` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.dao_rules` for the integration package.
 
 The schedule-rules/quest-definitions DAO lives in
-:mod:`core.dao_rules` (extracted in task d0b691d8); this module
-re-exports it so existing ``from .dao_rules import ...`` references
-inside the integration keep working.
+:mod:`custom_components.nestquest.core.dao_rules` (extracted in task
+d0b691d8); this module re-exports it so existing
+``from .dao_rules import ...`` references inside the integration keep
+working.
 """
 from __future__ import annotations
 
diff --git a/custom_components/nestquest/db.py b/custom_components/nestquest/db.py
index 78dfaec..b13a2e0 100644
--- a/custom_components/nestquest/db.py
+++ b/custom_components/nestquest/db.py
@@ -1,6 +1,6 @@
-"""Re-export of :mod:`core.db` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.db` for the integration package.
 
-The async SQLite wrapper lives in :mod:`core.db` (extracted in task
+The async SQLite wrapper lives in :mod:`custom_components.nestquest.core.db` (extracted in task
 d0b691d8) and is Home-Assistant-free: :class:`NestQuestDatabase` takes
 an executor callable rather than a ``hass`` object.  This module
 re-exports it and provides :func:`make_database`, a thin adapter that
diff --git a/custom_components/nestquest/migrations.py b/custom_components/nestquest/migrations.py
index f9fb72a..d51d3c7 100644
--- a/custom_components/nestquest/migrations.py
+++ b/custom_components/nestquest/migrations.py
@@ -1,6 +1,7 @@
-"""Re-export of :mod:`core.migrations` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.migrations` for the integration package.
 
-The versioned migration runner lives in :mod:`core.migrations`
+The versioned migration runner lives in
+:mod:`custom_components.nestquest.core.migrations`
 (extracted in task d0b691d8); this module re-exports it so existing
 ``from .migrations import ...`` references inside the integration keep
 working.
diff --git a/custom_components/nestquest/recurrence.py b/custom_components/nestquest/recurrence.py
index a3da9fb..7e72994 100644
--- a/custom_components/nestquest/recurrence.py
+++ b/custom_components/nestquest/recurrence.py
@@ -1,11 +1,10 @@
-"""Re-export of :mod:`core.recurrence` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.recurrence` for the integration package.
 
-The recurrence model lives in :mod:`core.recurrence` (extracted in task
-d0b691d8); this module re-exports it so existing
+The recurrence model lives in :mod:`custom_components.nestquest.core.recurrence`
+(extracted in task d0b691d8); this module re-exports it so existing
 ``from .recurrence import ...`` references inside the integration keep
 working.
 """
 from __future__ import annotations
 
 from .core.recurrence import *  # noqa: F401,F403
-from .core.recurrence import _month_end, _nth_weekday_of_month  # noqa: F401
diff --git a/custom_components/nestquest/schema.py b/custom_components/nestquest/schema.py
index b19b4f8..6ed278a 100644
--- a/custom_components/nestquest/schema.py
+++ b/custom_components/nestquest/schema.py
@@ -1,6 +1,7 @@
-"""Re-export of :mod:`core.schema` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.schema` for the integration package.
 
-The declarative schema DDL lives in :mod:`core.schema` (extracted in
+The declarative schema DDL lives in
+:mod:`custom_components.nestquest.core.schema` (extracted in
 task d0b691d8); this module re-exports it so existing
 ``from .schema import ...`` references inside the integration keep
 working.
diff --git a/custom_components/nestquest/store.py b/custom_components/nestquest/store.py
index 1c2e69f..e87a7d7 100644
--- a/custom_components/nestquest/store.py
+++ b/custom_components/nestquest/store.py
@@ -1,7 +1,9 @@
-"""Re-export of :mod:`core.store` for the integration package.
+"""Re-export of :mod:`custom_components.nestquest.core.store` for the integration package.
 
-The path resolver lives in :mod:`core.store` (extracted in task
-d0b691d8) and is Home-Assistant-free: :func:`core.store.async_get_db_path`
+The path resolver lives in
+:mod:`custom_components.nestquest.core.store` (extracted in task
+d0b691d8) and is Home-Assistant-free:
+:func:`custom_components.nestquest.core.store.async_get_db_path`
 takes the full database path.  This module re-exports it and provides
 the original ``async_get_db_path(hass)`` signature so the integration
 resolves the path from ``hass.config.path`` exactly as before.
@@ -23,7 +25,8 @@ async def async_get_db_path(hass: HomeAssistant) -> Path:
     """Return the absolute path to the NestQuest SQLite database file.
 
     Resolves the database file from ``hass.config.path`` and delegates to
-    :func:`core.store.async_get_db_path`, which ensures the parent
-    directory exists off the event loop via :func:`asyncio.to_thread`.
+    :func:`custom_components.nestquest.core.store.async_get_db_path`,
+    which ensures the parent directory exists off the event loop via
+    :func:`asyncio.to_thread`.
     """
     return await _core_async_get_db_path(hass.config.path(SQLITE_DB_FILENAME))
diff --git a/tests/test_config_flow.py b/tests/test_config_flow.py
index 246e59b..a6ecc2d 100644
--- a/tests/test_config_flow.py
+++ b/tests/test_config_flow.py
@@ -140,7 +140,7 @@ def test_flow_strings_match_translations(
 def test_no_hardcoded_domain_or_db_filename_in_new_modules() -> None:
     """Ensure no module other than const.py hardcodes the domain or db filename."""
     pkg_dir = Path(config_flow.__file__).parent
-    py_files = [f for f in pkg_dir.glob("*.py") if f.name not in ("const.py",)]
+    py_files = [f for f in pkg_dir.rglob("*.py") if f.name not in ("const.py",)]
 
     assert len(py_files) > 0, "No python modules found in package to check"
 
diff --git a/tests/test_const.py b/tests/test_const.py
index 361ca83..4d8592a 100644
--- a/tests/test_const.py
+++ b/tests/test_const.py
@@ -106,7 +106,7 @@ def test_window_clock_ranges_cover_every_window() -> None:
 def test_no_hardcoded_domain_or_db_filename_in_modules() -> None:
     """Ensure no module other than const.py hardcodes DOMAIN string or SQLITE_DB_FILENAME."""
     pkg_dir = Path(const.__file__).parent
-    py_files = [f for f in pkg_dir.glob("*.py") if f.name != "const.py"]
+    py_files = [f for f in pkg_dir.rglob("*.py") if f.name != "const.py"]
 
     assert len(py_files) > 0, "No python modules found in package to check"
 
diff --git a/tests/test_core_isolation.py b/tests/test_core_isolation.py
new file mode 100644
index 0000000..3ff816d
--- /dev/null
+++ b/tests/test_core_isolation.py
@@ -0,0 +1,119 @@
+"""Invariant: the bundled core package is self-contained.
+
+Every module under ``custom_components/nestquest/core/`` must be free of
+Home Assistant and must not climb out of the core package: no
+``homeassistant`` import, no relative import with level > 1, no absolute
+import of ``custom_components.nestquest.<something other than core>``,
+and no bare ``import core`` / ``from core``.  This guards the
+storage-layer extraction (task d0b691d8) from regressing into a
+HA-coupled or integration-coupled bundle.
+"""
+from __future__ import annotations
+
+import ast
+from pathlib import Path
+
+CORE_PKG = Path(
+    __import__(
+        "custom_components.nestquest.core", fromlist=["__file__"]
+    ).__file__
+).parent
+
+
+def _module_chain(base: str, name: str) -> str:
+    """Combined dotted path for ``from <base> import <name>``."""
+    return f"{base}.{name}" if base else name
+
+
+def _is_homeassistant(module: str) -> bool:
+    return module == "homeassistant" or module.startswith("homeassistant.")
+
+
+def _climbs_out_of_core(module: str) -> bool:
+    """An absolute path that reaches the integration package but not core."""
+    if module == "custom_components.nestquest":
+        return True
+    if module.startswith("custom_components.nestquest."):
+        rest = module[len("custom_components.nestquest."):]
+        head = rest.split(".", 1)[0]
+        return head != "core"
+    return False
+
+
+def _is_bare_core(module: str) -> bool:
+    """A bare ``core`` / ``core.*`` absolute reference (not the bundle)."""
+    return module == "core" or module.startswith("core.")
+
+
+def _scan(path: Path) -> list[str]:
+    tree = ast.parse(path.read_text(encoding="utf-8"), filename=str(path))
+    offenders: list[str] = []
+    for node in ast.walk(tree):
+        if isinstance(node, ast.Import):
+            for alias in node.names:
+                mod = alias.name
+                if _is_homeassistant(mod):
+                    offenders.append(
+                        f"{path.name}:{node.lineno} homeassistant import: import {mod}"
+                    )
+                if _is_bare_core(mod):
+                    offenders.append(
+                        f"{path.name}:{node.lineno} bare core import: import {mod}"
+                    )
+                if _climbs_out_of_core(mod):
+                    offenders.append(
+                        f"{path.name}:{node.lineno} climbs out of core: import {mod}"
+                    )
+        elif isinstance(node, ast.ImportFrom):
+            if node.level and node.level > 1:
+                offenders.append(
+                    f"{path.name}:{node.lineno} relative import climbs out "
+                    f"of core (level {node.level})"
+                )
+                continue
+            if node.level:
+                # relative level 1 stays inside core; nothing to check.
+                continue
+            base = node.module or ""
+            if _is_homeassistant(base):
+                offenders.append(
+                    f"{path.name}:{node.lineno} homeassistant import: from {base}"
+                )
+            if _is_bare_core(base):
+                offenders.append(
+                    f"{path.name}:{node.lineno} bare core import: from {base}"
+                )
+            if _climbs_out_of_core(base):
+                offenders.append(
+                    f"{path.name}:{node.lineno} climbs out of core: from {base}"
+                )
+            for alias in node.names:
+                combined = _module_chain(base, alias.name)
+                if _is_homeassistant(combined):
+                    offenders.append(
+                        f"{path.name}:{node.lineno} homeassistant import: "
+                        f"from {base} import {alias.name}"
+                    )
+                if _is_bare_core(combined):
+                    offenders.append(
+                        f"{path.name}:{node.lineno} bare core import: "
+                        f"from {base} import {alias.name}"
+                    )
+                if _climbs_out_of_core(combined):
+                    offenders.append(
+                        f"{path.name}:{node.lineno} climbs out of core: "
+                        f"from {base} import {alias.name}"
+                    )
+    return offenders
+
+
+def test_core_package_is_self_contained() -> None:
+    """No core module imports homeassistant or climbs out of the core package."""
+    py_files = sorted(CORE_PKG.rglob("*.py"))
+    assert py_files, "core package not found under custom_components/nestquest/core"
+    all_offenders: list[str] = []
+    for py_file in py_files:
+        all_offenders.extend(_scan(py_file))
+    assert all_offenders == [], (
+        "core package isolation violated:\n" + "\n".join(all_offenders)
+    )
diff --git a/tests/test_dao_matrix.py b/tests/test_dao_matrix.py
index 30f96d2..945471c 100644
--- a/tests/test_dao_matrix.py
+++ b/tests/test_dao_matrix.py
@@ -441,7 +441,7 @@ def test_completion_events_absolutely_no_mutation_path() -> None:
     )
     offenders = [
         py.name
-        for py in sorted(package.glob("*.py"))
+        for py in sorted(package.rglob("*.py"))
         if py.name != "__pycache__" and mutation.search(py.read_text())
     ]
     assert offenders == []
\ No newline at end of file
diff --git a/tests/test_recurrence_model.py b/tests/test_recurrence_model.py
index 8e12098..095ac03 100644
--- a/tests/test_recurrence_model.py
+++ b/tests/test_recurrence_model.py
@@ -276,7 +276,7 @@ def test_recurrence_module_imports_only_stdlib() -> None:
     from pathlib import Path
 
     source = Path(
-        __import__("custom_components.nestquest.recurrence",
+        __import__("custom_components.nestquest.core.recurrence",
                    fromlist=["__file__"]).__file__
     ).read_text()
     offenders = _scan_forbidden_imports(source)
diff --git a/tests/test_recurrence_monthly_day.py b/tests/test_recurrence_monthly_day.py
index aec763c..8830523 100644
--- a/tests/test_recurrence_monthly_day.py
+++ b/tests/test_recurrence_monthly_day.py
@@ -9,10 +9,10 @@ from custom_components.nestquest.recurrence import (
     RuleType,
     RuleValidationError,
     ScheduleRule,
-    _month_end,
     occurs_on,
     occurrences_between,
 )
+from custom_components.nestquest.core.recurrence import _month_end
 
 
 def _d(date: str) -> datetime.date:
diff --git a/tests/test_recurrence_monthly_weekday.py b/tests/test_recurrence_monthly_weekday.py
index 1d08be7..2e040e9 100644
--- a/tests/test_recurrence_monthly_weekday.py
+++ b/tests/test_recurrence_monthly_weekday.py
@@ -9,10 +9,10 @@ from custom_components.nestquest.recurrence import (
     RuleType,
     RuleValidationError,
     ScheduleRule,
-    _nth_weekday_of_month,
     occurs_on,
     occurrences_between,
 )
+from custom_components.nestquest.core.recurrence import _nth_weekday_of_month
 
 
 def _d(date: str) -> datetime.date: