diff --git a/.travis.yml b/.travis.yml
index a15d8d4c25..23a740532f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -27,24 +27,26 @@ env:
         - SYMFONY_DEPRECATIONS_HELPER=weak
 
 before_install:
-    - composer self-update
+    - if [[ "$deps" = "no" ]] && [[ "$TRAVIS_PHP_VERSION" =~ 5.[45] ]] && [[ "$TRAVIS_PULL_REQUEST" != "false" ]]; then export deps=skip; fi;
+    - if [ "$deps" != "skip" ]; then composer self-update; fi;
     - if [[ "$TRAVIS_PHP_VERSION" != "hhvm" ]]; then echo "memory_limit = -1" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini; fi;
     - if [[ "$TRAVIS_PHP_VERSION" = 5.* ]]; then phpenv config-rm xdebug.ini; fi;
     - if [[ "$TRAVIS_PHP_VERSION" = 5.* ]]; then echo "extension = mongo.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini; fi;
     - if [[ "$TRAVIS_PHP_VERSION" =~ 5.[34] ]]; then echo "extension = apc.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini; fi;
     - if [[ "$TRAVIS_PHP_VERSION" = 5.* ]]; 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" != "hhvm" ]]; then php -i; fi;
-    - ./phpunit install
+    - if [ "$deps" != "skip" ]; then ./phpunit install; fi;
     - export PHPUNIT="$(readlink -f ./phpunit)"
 
 install:
     - if [ "$TRAVIS_BRANCH" = "master" ]; then export COMPOSER_ROOT_VERSION=dev-master; else export COMPOSER_ROOT_VERSION="$TRAVIS_BRANCH".x-dev; fi;
     - 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 $COMPONENTS; fi;
+    - if [ "$deps" != "skip" ]; then COMPONENTS=$(find src/Symfony -mindepth 3 -type f -name phpunit.xml.dist -printf '%h\n'); fi;
+    - if [ "$deps" != "skip" ] && [ "$deps" != "no" ]; then php .travis.php $TRAVIS_COMMIT_RANGE $TRAVIS_BRANCH $COMPONENTS; fi;
 
 script:
     - if [ "$deps" = "no" ]; then echo "$COMPONENTS" | parallel --gnu 'echo -e "\\nRunning {} tests"; $PHPUNIT --exclude-group tty,benchmark,intl-data {}'; fi;
     - if [ "$deps" = "no" ]; then echo -e "\\nRunning tests requiring tty"; $PHPUNIT --group tty; fi;
     - if [ "$deps" = "high" ]; then echo "$COMPONENTS" | parallel --gnu -j10% 'echo -e "\\nRunning {} tests"; cd {}; composer --prefer-source update; $PHPUNIT --exclude-group tty,benchmark,intl-data'; fi;
     - if [ "$deps" = "low" ]; then echo "$COMPONENTS" | parallel --gnu -j10% 'echo -e "\\nRunning {} tests"; cd {}; composer --prefer-source --prefer-lowest --prefer-stable update; $PHPUNIT --exclude-group tty,benchmark,intl-data'; fi;
+    - if [ "$deps" = "skip" ]; then echo 'This matrix line is skipped for pull requests.'; fi;