diff --git a/README.org b/README.org
index 26f18c4..2c9f184 100644
--- a/README.org
+++ b/README.org
@@ -38,7 +38,7 @@
     python3 -m pip install -r requirements.txt
     # Or separately:
     pip install --upgrade pip
-    pip install ipython pyyaml pandas jupyter
+    pip install ipython pyyaml pandas jupyter pyflakes
   #+END_SRC
 
   "Install" for local development:
diff --git a/bin/sarif-digest b/bin/sarif-digest
index 94d2eec..eea15bd 100755
--- a/bin/sarif-digest
+++ b/bin/sarif-digest
@@ -1,6 +1,5 @@
 #!/usr/bin/env python
 import json
-import sarif_cli.traverse as S
 import sys
 
 # TODO command-line: sarif-digest [<file>]
diff --git a/bin/sarif-extract-multi b/bin/sarif-extract-multi
index b654ecb..a9b0321 100755
--- a/bin/sarif-extract-multi
+++ b/bin/sarif-extract-multi
@@ -9,7 +9,6 @@ from sarif_cli import typegraph
 from dataclasses import dataclass
 import sarif_cli.table_joins as tj
 import sys
-from collections import UserDict
 import pandas as pd
 
 #
diff --git a/bin/sarif-extract-tables b/bin/sarif-extract-tables
index 4869cc4..85c6fdc 100755
--- a/bin/sarif-extract-tables
+++ b/bin/sarif-extract-tables
@@ -18,7 +18,6 @@ import pathlib
 from sarif_cli import signature, signature_single
 from sarif_cli import typegraph
 import sys
-from collections import defaultdict
 import pandas as pd
 
 #
diff --git a/bin/sarif-labeled b/bin/sarif-labeled
index 9868a3d..cf22154 100755
--- a/bin/sarif-labeled
+++ b/bin/sarif-labeled
@@ -1,7 +1,6 @@
 #!/usr/bin/env python
 import argparse
 import json
-import sarif_cli.traverse as S
 import sys
 import collections
 
diff --git a/bin/sarif-list-files b/bin/sarif-list-files
index b009687..a3737c1 100755
--- a/bin/sarif-list-files
+++ b/bin/sarif-list-files
@@ -3,7 +3,6 @@ import argparse
 import json
 import sarif_cli.traverse as S
 import sys
-import collections
 
 parser = argparse.ArgumentParser(description='list source files referenced by sarif file')
 parser.add_argument('file', metavar='sarif-file', type=str,
diff --git a/bin/sarif-results-summary b/bin/sarif-results-summary
index 941db7a..2dfb990 100755
--- a/bin/sarif-results-summary
+++ b/bin/sarif-results-summary
@@ -2,9 +2,7 @@
 import argparse
 import json
 import sarif_cli.traverse as S
-import re
 import sys
-import collections
 
 parser = argparse.ArgumentParser(description='summary of results')
 parser.add_argument('file', metavar='sarif-file', type=str, help='input file, - for stdin')
diff --git a/sarif_cli/typegraph.py b/sarif_cli/typegraph.py
index afcde23..06bf62d 100644
--- a/sarif_cli/typegraph.py
+++ b/sarif_cli/typegraph.py
@@ -8,7 +8,7 @@ This file also contains some type graph reference values; these may be moved out
 separate files at some point.
 """
 from dataclasses import dataclass
-from typing import *
+from typing import Any, Dict, List, Tuple, Union
 import pandas as pd
 
 #
@@ -230,7 +230,7 @@ def _destructure_list(typegraph, node: str, tree: List):
                          id(value)))
                     # Next `value` on success
                     break           
-                except MissingFieldException as e:
+                except MissingFieldException:
                     # Re-raise if last available signature failed, otherwise try
                     # next `signature`
                     if (sigindex, sigtype) == signature[-1]:
@@ -265,14 +265,12 @@ def tagged_array_columns(typegraph, array_id):
         t8754_array_id  t8754_value_index t8754_type_at_index  t8754_id_or_value_at_index    
     """
     array_id = str(array_id)
-    typedef = 'Array' + array_id
     colheader = ('array_id', 'value_index', 'type_at_index', 'id_or_value_at_index')
     return { header:"t{:s}_{:s}".format(array_id, header) for header in colheader}
 
 
 def tagged_struct_columns(typegraph, struct_id):
     """ Return a dict mapping the struct column names to versions tagged with the id.
-    XX:
     """
     struct_id = str(struct_id)
     typedef = 'Struct' + struct_id