diff --git a/.travis.yml b/.travis.yml
index 16b7445b9..8b3b4cc44 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -53,8 +53,8 @@ matrix:
     - name: Lint Python code with flake8
       language: python
       python: 3.6
-      cache:
-        - pip
+      cache: pip
+      env: JOBCACHE=9
       install: pip install flake8
       script: flake8 . --count --exclude=./.*,./Lib,./vm/Lib  --select=E9,F63,F7,F82 --show-source --statistics