diff --git a/.travis.yml b/.travis.yml
index e6ab0b8214..f31f33860b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -37,7 +37,8 @@ before_install:
   - mysql -e 'create database myproject'
 
 install:
-  # Install Composer dependencies.
+  # Validate and install Composer dependencies.
+  - composer --verbose validate
   - composer --verbose install
 
   # Define build properties for the local test environment.
diff --git a/build.dist.xml b/build.dist.xml
index 9160059291..ccd6d52382 100644
--- a/build.dist.xml
+++ b/build.dist.xml
@@ -50,7 +50,8 @@
             <option name="account-mail" value="${drupal.admin.email}" />
             <param>${website.profile.name}</param>
             <!-- Disable sending of e-mails during installation. -->
-            <param>install_configure_form.update_status_module='array(FALSE,FALSE)'</param>
+            <param>install_configure_form.enable_update_status_module=NULL</param>
+            <param>install_configure_form.enable_update_status_emails=NULL</param>
         </drush>
     </target>
 
diff --git a/composer.json b/composer.json
index 4f173112ab..e6c85fe956 100644
--- a/composer.json
+++ b/composer.json
@@ -38,9 +38,8 @@
         "cweagans/composer-patches": "^1.6",
         "drupal-composer/drupal-scaffold": "^2.2",
         "drupal/console": "^1.0.1",
-        "drupal/core": "~8.0",
+        "drupal/core": "~8.3",
         "drush/drush": "~8.0",
-        "php": ">=5.5.9",
         "webflo/drupal-finder": "^1.0.0",
         "webmozart/path-util": "^2.3"
     },