diff --git a/capa/main.py b/capa/main.py
index 81b3c2d0..6138698a 100644
--- a/capa/main.py
+++ b/capa/main.py
@@ -20,7 +20,7 @@ import textwrap
 import itertools
 import contextlib
 import collections
-from typing import Any, Dict, List, Tuple, Callable
+from typing import Any, Dict, List, Tuple, Callable, Optional
 from pathlib import Path
 
 import halo
@@ -1060,7 +1060,7 @@ def handle_common_args(args):
         args.signatures = sigs_path
 
 
-def main(argv=None):
+def main(argv: Optional[List[str]] = None):
     if sys.version_info < (3, 8):
         raise UnsupportedRuntimeError("This version of capa can only be used with Python 3.8+")
 
diff --git a/tests/test_binja_features.py b/tests/test_binja_features.py
index 5819e0dc..c96b8c0c 100644
--- a/tests/test_binja_features.py
+++ b/tests/test_binja_features.py
@@ -59,7 +59,7 @@ def test_binja_feature_counts(sample, scope, feature, expected):
 def test_standalone_binja_backend():
     CD = Path(__file__).resolve().parent
     test_path = CD / ".." / "tests" / "data" / "Practical Malware Analysis Lab 01-01.exe_"
-    assert capa.main.main([test_path, "-b", capa.main.BACKEND_BINJA]) == 0
+    assert capa.main.main([str(test_path), "-b", capa.main.BACKEND_BINJA]) == 0
 
 
 @pytest.mark.skipif(binja_present is False, reason="Skip binja tests if the binaryninja Python API is not installed")