diff --git a/.travis.yml b/.travis.yml
index 1991ff1d..0c77fdd5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,9 +14,9 @@ addons:
       - mopidy
 
 env:
-  - TOX_ENV=py27
+  # Need to run 'py27' and 'test' together so that we can share coverage reports.
+  - TOX_ENV=py27,test
   - TOX_ENV=flake8
-  - TOX_ENV=test
   - TOX_ENV=eslint
   - TOX_ENV=csslint
   - TOX_ENV=tidy
@@ -33,4 +33,5 @@ script:
   - "tox -e $TOX_ENV"
 
 after_success:
-  - "if [ $TOX_ENV == 'test' ]; then pip install coveralls; coveralls --merge=.karma_coverage/coverage-final.json; fi"
+  # We just use 'coveralls-lcov' to convert lcov.info to JSON format.
+  - "if [ $TOX_ENV == 'py27,test' ]; then gem install coveralls-lcov; coveralls-lcov -v -n .karma_coverage/lcov.info > .karma_coverage/lcov.json; pip install coveralls; coveralls --merge=.karma_coverage/lcov.json; fi"
diff --git a/karma.conf.js b/karma.conf.js
index 11ab2534..57f7fa34 100644
--- a/karma.conf.js
+++ b/karma.conf.js
@@ -74,7 +74,6 @@ module.exports = function (config) {
             dir: '.karma_coverage/',
             reporters: [
                 { type: 'lcov', subdir: '.' },
-                { type: 'json', subdir: '.' },
                 { type: 'text' }
             ]
         }
diff --git a/tox.ini b/tox.ini
index 73fd03c1..22ff53ec 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,6 +2,7 @@
 envlist = py27, flake8, test, eslint, csslint, tidy
 
 [testenv]
+passenv = TRAVIS TRAVIS_JOB_ID TRAVIS_BRANCH
 sitepackages = true
 whitelist_externals =
     py.test
@@ -31,7 +32,6 @@ skip_install = true
 commands = flake8 --show-source --statistics --max-line-length 120 {posargs:mopidy_musicbox_webclient tests}
 
 [testenv:test]
-envdir = py27
 sitepackages = false
 whitelist_externals =
     /bin/bash