diff --git a/tools/scripts/lint.py b/tools/scripts/lint.py
new file mode 100644
index 0000000..5643a88
--- /dev/null
+++ b/tools/scripts/lint.py
@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+
+import glob
+import os
+import re
+import sys
+
+
+MAX_LINE_LENGTH = 100
+
+
+# Files with any of these as a substring of their filename are excluded from
+# consideration.
+FILES_TO_EXCLUDE = [
+  '/obj/',
+  '/bin/',
+  '/AssemblyInfo.cs',
+  '/Resource.Designer.cs',
+  'Shared/Levels.cs']
+
+
+def emit_error(filename, line_num, error):
+  print('%s:%d: %s' % (filename, line_num, error))
+
+
+def lint_csharp(filename):
+  errors = []
+  with open(filename) as f:
+    for i, line in enumerate(f):
+      line_num = i + 1
+      line = line[:-1]  # Strip trailing newline.
+      if len(line) > MAX_LINE_LENGTH:
+        if not re.match(r'\s*// https?:', line):
+          emit_error(filename, line_num, 'line too long')
+      if re.search(r'\t', line):
+        emit_error(filename, line_num, 'illegal \\t character')
+      if re.search(r'\r', line):
+        emit_error(filename, line_num, 'illegal \\r character')
+      if re.search(r'\s+$', line):
+        emit_error(filename, line_num, 'trailing whitespace')
+      if re.match(r'\s*//\S', line):
+        emit_error(filename, line_num, 'no space between // and comment')
+
+
+def main(args):
+  this_dir = os.path.dirname(os.path.realpath(__file__))
+  sneak_root = os.path.join(this_dir, '..', '..')
+  os.chdir(sneak_root)
+
+  csharp_files = sorted(glob.glob('**/*.cs', recursive=True))
+  # Remove generated files (of which there's lots).
+  for exclusion_pattern in FILES_TO_EXCLUDE:
+    csharp_files = [x for x in csharp_files if exclusion_pattern not in x]
+  print('checking %d files' % len(csharp_files))
+
+  for filename in csharp_files:
+    lint_csharp(filename)
+
+
+if __name__ == '__main__':
+  main(sys.argv[1:])