diff --git a/tests/conftest.py b/tests/conftest.py
index 4016ff0..3343fde 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1 +1,24 @@
-# Env var setup that must run before app.config is imported.
+from collections.abc import AsyncIterator, Awaitable, Callable
+
+import httpx
+import pytest
+from httpx import ASGITransport, AsyncClient
+
+from app.checker import EndpointChecker
+from app.main import app
+
+
+@pytest.fixture
+async def api_client() -> AsyncIterator[AsyncClient]:
+    async with app.router.lifespan_context(app):
+        async with AsyncClient(transport=ASGITransport(app=app), base_url="http://test") as client:
+            yield client
+
+
+async def public_resolver(host: str, port: int) -> list[str]:
+    return ["93.184.216.34"]
+
+
+def install_checker(handler: Callable[[httpx.Request], httpx.Response], resolver: Callable[[str, int], Awaitable[list[str]]] = public_resolver) -> None:
+    client = httpx.AsyncClient(transport=httpx.MockTransport(handler))
+    app.state.checker = EndpointChecker(client, timeout=1, max_redirects=2, max_response_bytes=1024, resolver=resolver)