diff --git a/edge/config.py b/edge/config.py
new file mode 100644
index 0000000..a5f6088
--- /dev/null
+++ b/edge/config.py
@@ -0,0 +1,43 @@
+from dataclasses import dataclass
+
+from edge.detectors.fall import FallConfig
+from edge.detectors.immobility import ImmobilityConfig
+from edge.detectors.ghost import GhostConfig
+from edge.detectors.zone import ZoneConfig
+from edge.engine import EngineConfig
+
+
+@dataclass
+class Config:
+    device_id: str
+    camera_id: str
+    cafe24_url: str
+    secret: str
+    fall: FallConfig
+    immobility: ImmobilityConfig
+    ghost: GhostConfig
+    zone: ZoneConfig
+    engine: EngineConfig
+
+
+def _f(env: dict, key: str, default: float) -> float:
+    return float(env[key]) if key in env else default
+
+
+def load_config(env: dict) -> Config:
+    camera_id = env.get("CAMERA_ID", "cam-01")
+    fall = FallConfig(
+        prone_confirm_s=_f(env, "FALL_PRONE_S", 3.0),
+        no_motion_s=_f(env, "FALL_NO_MOTION_S", 10.0),
+    )
+    immobility = ImmobilityConfig(immobile_s=_f(env, "IMMOBILE_S", 120.0))
+    ghost = GhostConfig(reappear_s=_f(env, "GHOST_REAPPEAR_S", 10.0))
+    zone = ZoneConfig(debounce_s=_f(env, "ZONE_DEBOUNCE_S", 0.75))
+    engine = EngineConfig(camera_id=camera_id, cooldown_s=_f(env, "COOLDOWN_S", 30.0))
+    return Config(
+        device_id=env.get("DEVICE_ID", "pi-unknown"),
+        camera_id=camera_id,
+        cafe24_url=env.get("CAFE24_URL", ""),
+        secret=env.get("DEVICE_SECRET", ""),
+        fall=fall, immobility=immobility, ghost=ghost, zone=zone, engine=engine,
+    )
diff --git a/tests/test_config.py b/tests/test_config.py
new file mode 100644
index 0000000..5960f61
--- /dev/null
+++ b/tests/test_config.py
@@ -0,0 +1,23 @@
+from edge.config import load_config
+
+def test_defaults_when_env_empty():
+    cfg = load_config({})
+    assert cfg.device_id == "pi-unknown"
+    assert cfg.fall.prone_confirm_s == 3.0
+    assert cfg.fall.no_motion_s == 10.0
+
+def test_env_overrides():
+    env = {
+        "DEVICE_ID": "pi-w1", "CAMERA_ID": "cam-9",
+        "CAFE24_URL": "https://x/api/events", "DEVICE_SECRET": "s",
+        "FALL_PRONE_S": "2.0", "FALL_NO_MOTION_S": "8",
+        "IMMOBILE_S": "90", "COOLDOWN_S": "45",
+    }
+    cfg = load_config(env)
+    assert cfg.device_id == "pi-w1"
+    assert cfg.camera_id == "cam-9"
+    assert cfg.fall.prone_confirm_s == 2.0
+    assert cfg.fall.no_motion_s == 8.0
+    assert cfg.immobility.immobile_s == 90.0
+    assert cfg.engine.cooldown_s == 45.0
+    assert cfg.engine.camera_id == "cam-9"