diff --git a/.github/mypy/mypy.ini b/.github/mypy/mypy.ini
index 603f2e42..81614afe 100644
--- a/.github/mypy/mypy.ini
+++ b/.github/mypy/mypy.ini
@@ -1,5 +1,11 @@
 [mypy]
 
+exclude = (?x)(
+    ^capa/render/proto/__init__.py$
+    | ^tests/_test_proto.py$
+    | ^capa/ida/helpers.py$
+  )
+
 [mypy-halo.*]
 ignore_missing_imports = True
 
diff --git a/tests/_test_proto.py b/tests/_test_proto.py
index f45282b7..412db8f6 100644
--- a/tests/_test_proto.py
+++ b/tests/_test_proto.py
@@ -150,6 +150,7 @@ def assert_meta(meta: rd.Metadata, dst: capa_pb2.Metadata):
     assert list(meta.analysis.rules) == dst.analysis.rules
     assert capa.render.proto.addr_to_pb2(meta.analysis.base_address) == dst.analysis.base_address
 
+    assert isinstance(rd.Metadata.analysis.layout, rd.StaticLayout)
     assert len(meta.analysis.layout.functions) == len(dst.analysis.layout.functions)
     for rd_f, proto_f in zip(meta.analysis.layout.functions, dst.analysis.layout.functions):
         assert capa.render.proto.addr_to_pb2(rd_f.address) == proto_f.address