diff --git a/app/main.py b/app/main.py
index de0f8ff..6826c1c 100644
--- a/app/main.py
+++ b/app/main.py
@@ -1,12 +1,46 @@
-from fastapi import FastAPI
+from contextlib import asynccontextmanager
+
+from fastapi import FastAPI, Depends
+
+from app.api.v1.entities import router as entities_router
+from app.ha.client import HaClient, HaClientSettings
+from app.ha.reader import HaReader
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    settings = HaClientSettings(
+        url=app.state.settings.ha_url,
+        token=app.state.settings.ha_token,
+    )
+    client = HaClient(settings=settings)
+    app.state.ha_reader = HaReader(client=client)
+    yield
+
 
 app = FastAPI(
     title="SillyHome Next API",
     description="Lokales Smart-Home-Intelligenzsystem für Home Assistant.",
     version="0.1.0",
+    lifespan=lifespan,
 )
 
 
+class Settings:
+    ha_url: str
+    ha_token: str
+
+
+app.state.settings = Settings()
+
+
+def get_ha_reader() -> HaReader:
+    return app.state.ha_reader
+
+
+app.include_router(entities_router, dependencies=[Depends(get_ha_reader)])
+
+
 @app.get("/health")
 def health() -> dict[str, str]:
     return {"status": "ok"}
@@ -14,4 +48,4 @@ def health() -> dict[str, str]:
 
 @app.get("/")
 def root() -> dict[str, str]:
-    return {"service": "sillyhome-next", "docs": "/docs"}
+    return {"service": "sillyhome-next", "docs": "/docs"}
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