diff --git a/.coveragerc b/.coveragerc
index 41c432b..e60703c 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -16,6 +16,8 @@ exclude_lines =
     def __repr__
     if self\.debug
 
+    case never:
+    assert_never
     raise AssertionError
     raise NotImplementedError
 
diff --git a/synth.yaml b/synth.yaml
index 2b4ef6c..31583df 100644
--- a/synth.yaml
+++ b/synth.yaml
@@ -33,3 +33,4 @@ triggers:
       - tests/
       - docs/examples/
       - pyproject.toml
+      - .coveragerc
diff --git a/synthesize/config.py b/synthesize/config.py
index 0637989..5f129e6 100644
--- a/synthesize/config.py
+++ b/synthesize/config.py
@@ -194,8 +194,8 @@ def mermaid(self) -> str:
                         seen_watches.add(h)
                         lines.append(f'w_{h}[("{text}")]')
                     lines.append(f"w_{h} -->|👁| {node.id}")
-                case _:
-                    assert_never(node.trigger)
+                case never:
+                    assert_never(never)
 
         return "\n  ".join(lines).strip()
 
diff --git a/tests/test_config.py b/tests/test_config.py
index d199ddf..196c049 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -18,7 +18,8 @@
     random_color,
 )
 
-EXAMPLES = list((Path(__file__).parent.parent / "docs" / "examples").iterdir())
+ROOT = Path(__file__).parent.parent
+EXAMPLES = [*(ROOT / "docs" / "examples").iterdir(), ROOT / "synth.yaml"]
 
 
 @pytest.mark.parametrize("example", EXAMPLES)