diff --git a/.travis.yml b/.travis.yml
index 91a4cefd..e77adc6a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,6 +12,10 @@ php:
 
 matrix:
   include:
+    - php: 5.3
+      env: COMPOSER_OPTIONS="--prefer-lowest"
+    - php: 7.0
+      env: COMPOSER_OPTIONS="--prefer-lowest"
     - php: 7.1
       env: TEST_COVERAGE=true
   allow_failures:
@@ -26,7 +30,7 @@ before_install:
   - composer self-update
   - if [[ $TEST_COVERAGE ]]; then PHPUNIT_FLAGS="--coverage-clover clover.xml"; fi
 
-install: travis_retry composer install --no-interaction --prefer-dist
+install: travis_retry composer update --no-interaction --prefer-dist --prefer-stable $COMPOSER_OPTIONS
 
 script:
   - vendor/bin/phpunit -v $PHPUNIT_FLAGS
diff --git a/composer.json b/composer.json
index 8f95e787..561e0ce7 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,12 @@
     "require": {
         "php": ">=5.3.3",
         "sentry/sentry": ">=1.5.0",
-        "symfony/framework-bundle": ">=2.4.0"
+        "symfony/config": "^2.4|^3.0",
+        "symfony/console": "^2.4|^3.0",
+        "symfony/dependency-injection": "^2.4|^3.0",
+        "symfony/event-dispatcher": "^2.4|^3.0",
+        "symfony/http-kernel": "^2.4|^3.0",
+        "symfony/security-core": "^2.4|^3.0"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^1.8.0",