diff --git a/.travis.yml b/.travis.yml
index aa0ac21a6f..40a0036958 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -36,20 +36,20 @@ before_install:
     - if [[ "$TRAVIS_PHP_VERSION" != "nightly" ]] && [[ "$TRAVIS_PHP_VERSION" != "hhvm" ]]; then (pecl install -f memcached-2.1.0 && echo "extension = memcache.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini) || echo "Let's continue without memcache extension"; fi;
     - if [[ "$TRAVIS_PHP_VERSION" != "nightly" ]] && [[ "$TRAVIS_PHP_VERSION" != "hhvm" ]]; then (cd src/Symfony/Component/Debug/Resources/ext && phpize && ./configure && make && echo "extension = $(pwd)/modules/symfony_debug.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini); fi;
     - if [[ "$TRAVIS_PHP_VERSION" != "nightly" ]] && [[ "$TRAVIS_PHP_VERSION" != "hhvm" ]]; then php -i; fi;
+    # Build a standalone phpunit without symfony/yaml and that works around https://github.com/sebastianbergmann/phpunit-mock-objects/issues/223
+    - (mkdir phpunit && cd phpunit && wget https://github.com/sebastianbergmann/phpunit/archive/4.7.zip && unzip 4.7.zip && cd phpunit-4.7 && composer remove --no-update symfony/yaml && composer require --prefer-source phpunit/phpunit-mock-objects '2.3.0')
+    - export PHPUNIT="$(readlink -f ./phpunit/phpunit-4.7/phpunit) --colors=always"
     # Set the COMPOSER_ROOT_VERSION to the right version according to the branch being built
     - if [ "$TRAVIS_BRANCH" = "master" ]; then export COMPOSER_ROOT_VERSION=dev-master; else export COMPOSER_ROOT_VERSION="$TRAVIS_BRANCH".x-dev; fi;
 
 install:
     - if [ "$deps" = "no" ]; then export SYMFONY_DEPRECATIONS_HELPER=strict; fi;
-    - composer require --no-update phpunit/phpunit '*'
-    - composer require --no-update phpunit/phpunit-mock-objects '2.3.0' # See https://github.com/sebastianbergmann/phpunit-mock-objects/issues/223
-    - composer update --prefer-stable --prefer-source phpunit/phpunit
+    - if [ "$deps" = "no" ]; then composer --prefer-source install; fi;
     - components=$(find src/Symfony -mindepth 3 -type f -name phpunit.xml.dist -printf '%h\n')
     - if [ "$deps" != "no" ]; then php .travis.php $TRAVIS_COMMIT_RANGE $TRAVIS_BRANCH $components; fi;
-    - PHPUNIT="$(readlink -f ./vendor/bin/phpunit) --colors=always"
 
 script:
-    - if [ "$deps" = "no" ]; then echo "$components" | parallel --gnu --keep-order 'echo -e "\\nRunning {} tests"; '$PHPUNIT' --exclude-group tty,benchmark,intl-data {} || (echo -e "\\e[41mKO\\e[0m {}" && $(exit 1));'; fi;
+    - if [ "$deps" = "no" ]; then echo "$components" | parallel --gnu --keep-order 'echo -e "\\nRunning {} tests"; $PHPUNIT --exclude-group tty,benchmark,intl-data {} || (echo -e "\\e[41mKO\\e[0m {}" && $(exit 1));'; fi;
     - if [ "$deps" = "no" ]; then echo -e "\\nRunning tests requiring tty"; $PHPUNIT --group tty || (echo -e "\\e[41mKO\\e[0m tty group" && $(exit 1)); fi;
-    - if [ "$deps" = "high" ]; then echo "$components" | parallel --gnu --keep-order -j10% 'echo -e "\\nRunning {} tests"; cd {}; composer --prefer-source update; '$PHPUNIT' --exclude-group tty,benchmark,intl-data || (echo -e "\\e[41mKO\\e[0m {}" && $(exit 1));'; fi;
-    - if [ "$deps" = "low" ]; then echo "$components" | parallel --gnu --keep-order -j10% 'echo -e "\\nRunning {} tests"; cd {}; composer --prefer-source --prefer-lowest --prefer-stable update; '$PHPUNIT' --exclude-group tty,benchmark,intl-data || (echo -e "\\e[41mKO\\e[0m {}" && $(exit 1));'; fi;
+    - if [ "$deps" = "high" ]; then echo "$components" | parallel --gnu --keep-order -j10% 'echo -e "\\nRunning {} tests"; cd {}; composer --prefer-source update; $PHPUNIT --exclude-group tty,benchmark,intl-data || (echo -e "\\e[41mKO\\e[0m {}" && $(exit 1));'; fi;
+    - if [ "$deps" = "low" ]; then echo "$components" | parallel --gnu --keep-order -j10% 'echo -e "\\nRunning {} tests"; cd {}; composer --prefer-source --prefer-lowest --prefer-stable update; $PHPUNIT --exclude-group tty,benchmark,intl-data || (echo -e "\\e[41mKO\\e[0m {}" && $(exit 1));'; fi;
diff --git a/src/Symfony/Bundle/TwigBundle/composer.json b/src/Symfony/Bundle/TwigBundle/composer.json
index 61c85d33e3..b52e497b67 100644
--- a/src/Symfony/Bundle/TwigBundle/composer.json
+++ b/src/Symfony/Bundle/TwigBundle/composer.json
@@ -30,6 +30,7 @@
         "symfony/config": "~2.2",
         "symfony/routing": "~2.1",
         "symfony/templating": "~2.1",
+        "symfony/yaml": "~2.3",
         "symfony/framework-bundle": "~2.7"
     },
     "autoload": {