diff --git a/palmer/main.py b/palmer/main.py
index a034a21..73bb23f 100644
--- a/palmer/main.py
+++ b/palmer/main.py
@@ -388,7 +388,7 @@ async def artifact_page(token: str):
 async def icon_png():
     """The page's favicon and apple-touch-icon. No token: it is the same mark
     for everyone and carries no one's data."""
-    from cards import render_icon
+    from palmer.cards import render_icon
     return Response(content=render_icon(), media_type="image/png",
                     headers={"Cache-Control": "public, max-age=86400"})
 
diff --git a/tests/test_page.py b/tests/test_page.py
index 7849638..603e429 100644
--- a/tests/test_page.py
+++ b/tests/test_page.py
@@ -1037,3 +1037,11 @@ def test_the_description_leads_with_the_weather_when_named(self):
 
     def test_the_icon_is_a_png(self):
         assert cards.render_icon()[:8] == b"\x89PNG\r\n\x1a\n"
+
+    def test_the_icon_route_serves_it(self):
+        """The route imported `cards` by its pre-package name and 500'd in
+        production while every unit test of render_icon passed."""
+        from fastapi.testclient import TestClient
+        from palmer.main import app
+        r = TestClient(app).get("/icon.png")
+        assert r.status_code == 200 and r.headers["content-type"] == "image/png"