improve dev tooling

.vscode/settings.json

@@ -2,6 +2,7 @@
     "python.formatting.provider": "none",
     "python.linting.mypyEnabled": true,
     "python.linting.flake8Enabled": true,
+    "editor.formatOnSave": true,
     "[python]": {
         "editor.defaultFormatter": "ms-python.black-formatter",
     }