diff --git a/pyproject.toml b/pyproject.toml
index bbcd6af..31259bc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -56,6 +56,12 @@ dependencies = [
     # default — fine for single-replica deploys. Multi-replica rollouts can
     # swap the storage backend via slowapi's `storage_uri` (Redis, Memcached).
     "slowapi>=0.1.9",
+    # LLM provider SDKs — core (not dev) because connectors/llm/*_provider.py
+    # is imported by services/{corporate_memory, verification_detector} which
+    # the scheduler drives in production. Promoted from [dev] in #176 to fix
+    # ModuleNotFoundError boot loops on default Compose deploys.
+    "anthropic>=0.30.0",
+    "openai>=1.30.0",
 ]
 
 [project.optional-dependencies]
@@ -66,8 +72,6 @@ dev = [
     "pytest-timeout>=2.0.0",
     "pytest-xdist>=3.0.0",
     "faker>=24.0.0",
-    "anthropic>=0.30.0",
-    "openai>=1.30.0",
     # jsonschema validates the corporate-memory extraction-tool golden fixtures
     # under tests/test_corporate_memory_v1.py (extraction.json, correction.json,
     # confidence_calibration.json). Production code does not depend on it.
diff --git a/tests/test_packaging.py b/tests/test_packaging.py
new file mode 100644
index 0000000..8b5fb44
--- /dev/null
+++ b/tests/test_packaging.py
@@ -0,0 +1,83 @@
+"""Packaging regression tests — guard against silent prod-vs-dev dep drift.
+
+`anthropic` and `openai` are imported by `connectors/llm/anthropic_provider.py`
+and `connectors/llm/openai_compat.py`. Those modules run in production from
+`services/corporate_memory` and `services/verification_detector`. If they
+slip back into `[project.optional-dependencies].dev` the Dockerfile (which
+only installs core deps) will boot-loop on `ModuleNotFoundError`. See #176.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+
+def _read_pyproject() -> dict:
+    """Load pyproject.toml from the repo root."""
+    try:
+        import tomllib  # py3.11+
+    except ImportError:  # pragma: no cover
+        import tomli as tomllib  # type: ignore
+
+    root = Path(__file__).resolve().parent.parent
+    with (root / "pyproject.toml").open("rb") as f:
+        return tomllib.load(f)
+
+
+def test_anthropic_is_a_core_dependency():
+    """anthropic must live in [project].dependencies, not [dev].
+
+    Production code (connectors/llm/anthropic_provider.py) imports the SDK
+    unconditionally. Demoting it to dev resurrects the #176 boot loop.
+    """
+    cfg = _read_pyproject()
+    core = cfg["project"]["dependencies"]
+    assert any(dep.startswith("anthropic") for dep in core), (
+        "anthropic must be in [project].dependencies — see #176"
+    )
+
+
+def test_openai_is_a_core_dependency():
+    """openai must live in [project].dependencies, not [dev]."""
+    cfg = _read_pyproject()
+    core = cfg["project"]["dependencies"]
+    assert any(dep.startswith("openai") for dep in core), (
+        "openai must be in [project].dependencies — see #176"
+    )
+
+
+def test_anthropic_not_in_optional_dev_extras():
+    """Belt-and-suspenders: dev extras should not double-list anthropic."""
+    cfg = _read_pyproject()
+    dev = cfg["project"].get("optional-dependencies", {}).get("dev", [])
+    assert not any(dep.startswith("anthropic") for dep in dev), (
+        "anthropic should not be duplicated in [dev] — keep it core-only"
+    )
+
+
+def test_openai_not_in_optional_dev_extras():
+    """Belt-and-suspenders: dev extras should not double-list openai."""
+    cfg = _read_pyproject()
+    dev = cfg["project"].get("optional-dependencies", {}).get("dev", [])
+    assert not any(dep.startswith("openai") for dep in dev), (
+        "openai should not be duplicated in [dev] — keep it core-only"
+    )
+
+
+def test_llm_provider_modules_import_cleanly():
+    """A fresh interpreter with only core deps installed must import the
+    LLM provider modules without ImportError. This is the actual behavior
+    that breaks the scheduler container when anthropic/openai are dev-only.
+    """
+    # Just importing here proves the deps resolve in the active env. The
+    # pyproject.toml assertions above keep the contract going forward.
+    import importlib
+
+    for mod in (
+        "connectors.llm.anthropic_provider",
+        "connectors.llm.openai_compat",
+        "connectors.llm.factory",
+    ):
+        importlib.import_module(mod)