--- a/.flake8
+++ b/.flake8
@@ -1,8 +1,9 @@
 [flake8]
 # See http://pep8.readthedocs.io/en/latest/intro.html#configuration
 ignore = E121, E123, E126, E129, E133, E226, E241, E242, E704, W503, E402, E741
 max-line-length = 99
 exclude =
     browser/extensions/mortar/ppapi/,
+    build/pymake/,
     testing/mochitest/pywebsocket,
     tools/lint/test/files,

--- a/tools/lint/flake8.yml
+++ b/tools/lint/flake8.yml
@@ -1,16 +1,15 @@
 ---
 flake8:
     description: Python linter
     include:
-        - build/*.py
-        - build/moz.configure/*.configure
-        - config/check_macroassembler_style.py
-        - config/mozunit
+        - browser/
+        - build/
+        - config/
         - configure.py
         - layout/tools/reftest
         - python/mach
         - python/mach_commands.py
         - python/mozboot
         - python/mozbuild/mozpack/path.py
         - python/mozlint
         - python/mozterm