1 files changed, 3 insertions, 0 deletions
diff --git a/tox.ini b/tox.ini
index 056ca4a..f4e5734 100644
--- a/tox.ini
+++ b/tox.ini
@@ -44,18 +44,21 @@ basepython =
     python3.4
 setenv =
     PURE_PYTHON = 1
+    PIP_CACHE_DIR = {envdir}/.cache
 
 [testenv:py35-pure]
 basepython =
     python3.5
 setenv =
     PURE_PYTHON = 1
+    PIP_CACHE_DIR = {envdir}/.cache
 
 [testenv:py27-pure]
 basepython =
     python3.4
 setenv =
     PURE_PYTHON = 1
+    PIP_CACHE_DIR = {envdir}/.cache
 
 [testenv:coverage]
 usedevelop = true