1 files changed, 6 insertions, 0 deletions

diff --git a/tox.ini b/tox.ini
index 984b3ac..c22096d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,8 @@
 [tox]
 envlist =
     py27,py35,py36,py37,pypy,pypy3,coverage,docs
+# Note: if you add new Python versions, please add them to
+# [testenv:coverage] depends as well!
 
 [testenv]
 usedevelop = true
@@ -22,6 +24,10 @@ commands =
     coverage html
     coverage xml
     coverage report --fail-under=100 --show-missing
+# parallel mode: make sure all builds complete before we run this one
+depends =
+    py27,py35,py36,py37,pypy,pypy3
+parallel_show_output = true
 
 [testenv:docs]
 basepython =