diff --git a/.travis.yml b/.travis.yml
index 34a4e5f633..102a024475 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,6 +8,8 @@ php:
   - '5.6'
   - '7.0'
   - '7.1'
+  - '7.2'
+  - nightly
 
 matrix:
   include:
@@ -18,6 +20,8 @@ matrix:
     - PHPCS_VERSION=2.9.1
     - LOCALE_GEN=1
     - ENABLE_LDAP=1
+  allow_failures:
+    - php: nightly
 
 services:
   - mysql
diff --git a/library/Icinga/Authentication/User/DbUserBackend.php b/library/Icinga/Authentication/User/DbUserBackend.php
index 6a2e2f6463..8cf4f5f401 100644
--- a/library/Icinga/Authentication/User/DbUserBackend.php
+++ b/library/Icinga/Authentication/User/DbUserBackend.php
@@ -117,7 +117,7 @@ protected function initializeFilterColumns()
      *
      * @return void
      */
-    public function insert($table, array $bind)
+    public function insert($table, array $bind, array $types = array())
     {
         $this->requireTable($table);
         $bind['created_at'] = date('Y-m-d H:i:s');
@@ -138,7 +138,7 @@ public function insert($table, array $bind)
      * @param   array   $bind
      * @param   Filter  $filter
      */
-    public function update($table, array $bind, Filter $filter = null)
+    public function update($table, array $bind, Filter $filter = null, array $types = array())
     {
         $this->requireTable($table);
         $bind['last_modified'] = date('Y-m-d H:i:s');
diff --git a/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php b/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php
index 844b6da3c9..17562d2f43 100644
--- a/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php
+++ b/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php
@@ -130,7 +130,7 @@ protected function initializeFilterColumns()
      * @param   string  $table
      * @param   array   $bind
      */
-    public function insert($table, array $bind)
+    public function insert($table, array $bind, array $types = array())
     {
         $bind['created_at'] = date('Y-m-d H:i:s');
         parent::insert($table, $bind);
@@ -143,7 +143,7 @@ public function insert($table, array $bind)
      * @param   array   $bind
      * @param   Filter  $filter
      */
-    public function update($table, array $bind, Filter $filter = null)
+    public function update($table, array $bind, Filter $filter = null, array $types = array())
     {
         $bind['last_modified'] = date('Y-m-d H:i:s');
         parent::update($table, $bind, $filter);
diff --git a/library/Icinga/Chart/Donut.php b/library/Icinga/Chart/Donut.php
index 1efc9546be..74f93d7d80 100644
--- a/library/Icinga/Chart/Donut.php
+++ b/library/Icinga/Chart/Donut.php
@@ -344,7 +344,7 @@ protected function encode($content)
 
     protected function renderAttributes(array $attributes)
     {
-        $html = [];
+        $html = array();
 
         foreach ($attributes as $name => $value) {
             if ($value === null) {
diff --git a/library/Icinga/Data/Filter/FilterQueryString.php b/library/Icinga/Data/Filter/FilterQueryString.php
index 692f7da935..2a36f78373 100644
--- a/library/Icinga/Data/Filter/FilterQueryString.php
+++ b/library/Icinga/Data/Filter/FilterQueryString.php
@@ -155,7 +155,7 @@ protected function readFilters($nestingLevel = 0, $op = null)
                     }
                 }
 
-                if ($op === null && count($filters > 0) && ($next === '&' || $next === '|')) {
+                if ($op === null && count($filters) > 0 && ($next === '&' || $next === '|')) {
                     $op = $next;
                     continue;
                 }
diff --git a/library/Icinga/File/Storage/TemporaryLocalFileStorage.php b/library/Icinga/File/Storage/TemporaryLocalFileStorage.php
index 05d633588e..6fd751c783 100644
--- a/library/Icinga/File/Storage/TemporaryLocalFileStorage.php
+++ b/library/Icinga/File/Storage/TemporaryLocalFileStorage.php
@@ -41,7 +41,7 @@ public function __destruct()
         foreach ($directoryIterator as $path => $entry) {
             /** @var \SplFileInfo $entry */
 
-            if ($entry->isDir()) {
+            if ($entry->isDir() && ! $entry->isLink()) {
                 rmdir($path);
             } else {
                 unlink($path);
diff --git a/library/Icinga/Web/Form/Element/Note.php b/library/Icinga/Web/Form/Element/Note.php
index 5344fb31cb..9569dee55c 100644
--- a/library/Icinga/Web/Form/Element/Note.php
+++ b/library/Icinga/Web/Form/Element/Note.php
@@ -48,7 +48,7 @@ public function init()
      *
      * @return  bool            Always true
      */
-    public function isValid($value)
+    public function isValid($value, $context = null)
     {
         return true;
     }
diff --git a/library/Icinga/Web/Session.php b/library/Icinga/Web/Session.php
index e6f7218ad2..40df89f9e4 100644
--- a/library/Icinga/Web/Session.php
+++ b/library/Icinga/Web/Session.php
@@ -29,7 +29,7 @@ class Session
     public static function create(BaseSession $session = null)
     {
         if ($session === null) {
-            self::$session = new PhpSession();
+            self::$session = PhpSession::create();
         } else {
             self::$session = $session;
         }
diff --git a/library/Icinga/Web/Session/Php72Session.php b/library/Icinga/Web/Session/Php72Session.php
new file mode 100644
index 0000000000..9003d7e1fc
--- /dev/null
+++ b/library/Icinga/Web/Session/Php72Session.php
@@ -0,0 +1,121 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Session;
+
+use Icinga\Application\Logger;
+use Icinga\Exception\ConfigurationError;
+use Icinga\Web\Cookie;
+
+/**
+ * Session implementation in PHP
+ */
+class Php72Session extends PhpSession
+{
+    /**
+     * Open a PHP session
+     */
+    protected function open()
+    {
+        session_name($this->sessionName);
+
+        $cookie = new Cookie('bogus');
+        session_set_cookie_params(
+            0,
+            $cookie->getPath(),
+            $cookie->getDomain(),
+            $cookie->isSecure(),
+            true
+        );
+
+        session_start(array(
+            'use_cookies'       => true,
+            'use_only_cookies'  => true,
+            'use_trans_sid'     => false
+        ));
+    }
+
+    /**
+     * Read all values written to the underling session and make them accessible.
+     */
+    public function read()
+    {
+        $this->clear();
+        $this->open();
+
+        foreach ($_SESSION as $key => $value) {
+            if (strpos($key, self::NAMESPACE_PREFIX) === 0) {
+                $namespace = new SessionNamespace();
+                $namespace->setAll($value);
+                $this->namespaces[substr($key, strlen(self::NAMESPACE_PREFIX))] = $namespace;
+            } else {
+                $this->set($key, $value);
+            }
+        }
+
+        session_write_close();
+    }
+
+    /**
+     * Write all values of this session object to the underlying session implementation
+     */
+    public function write()
+    {
+        $this->open();
+
+        foreach ($this->removed as $key) {
+            unset($_SESSION[$key]);
+        }
+        foreach ($this->values as $key => $value) {
+            $_SESSION[$key] = $value;
+        }
+        foreach ($this->removedNamespaces as $identifier) {
+            unset($_SESSION[self::NAMESPACE_PREFIX . $identifier]);
+        }
+        foreach ($this->namespaces as $identifier => $namespace) {
+            $_SESSION[self::NAMESPACE_PREFIX . $identifier] = $namespace->getAll();
+        }
+
+        session_write_close();
+    }
+
+    /**
+     * Delete the current session, causing all session information to be lost
+     */
+    public function purge()
+    {
+        $this->open();
+        $_SESSION = array();
+        $this->clear();
+        session_destroy();
+        $this->clearCookies();
+        session_write_close();
+    }
+
+    /**
+     * @see Session::getId()
+     */
+    public function getId()
+    {
+        if (($id = session_id()) === '') {
+            // Make sure we actually get a id
+            $this->open();
+            session_write_close();
+            $id = session_id();
+        }
+
+        return $id;
+    }
+
+    /**
+     * Assign a new sessionId to the currently active session
+     */
+    public function refreshId()
+    {
+        $this->open();
+        if ($this->exists()) {
+            session_regenerate_id();
+        }
+        session_write_close();
+    }
+}
diff --git a/library/Icinga/Web/Session/PhpSession.php b/library/Icinga/Web/Session/PhpSession.php
index e00544cf9b..36dd84e9dd 100644
--- a/library/Icinga/Web/Session/PhpSession.php
+++ b/library/Icinga/Web/Session/PhpSession.php
@@ -33,6 +33,21 @@ class PhpSession extends Session
      */
     protected $sessionName = 'Icingaweb2';
 
+    /**
+     * Create a new PHPSession object using the provided options (if any)
+     *
+     * @param   array   $options    An optional array of ini options to set
+     *
+     * @return  static
+     *
+     * @throws  ConfigurationError
+     * @see     http://php.net/manual/en/session.configuration.php
+     */
+    public static function create(array $options = null)
+    {
+        return version_compare(PHP_VERSION, '7.2.0') < 0 ? new self($options) : new Php72Session($options);
+    }
+
     /**
      * Create a new PHPSession object using the provided options (if any)
      *
diff --git a/modules/monitoring/application/views/helpers/PluginOutput.php b/modules/monitoring/application/views/helpers/PluginOutput.php
index 5224185bcb..2a8e300f40 100644
--- a/modules/monitoring/application/views/helpers/PluginOutput.php
+++ b/modules/monitoring/application/views/helpers/PluginOutput.php
@@ -163,8 +163,14 @@ protected function getPurifier()
         if (self::$purifier === null) {
             require_once 'HTMLPurifier/Bootstrap.php';
             require_once 'HTMLPurifier.php';
+
+            $oldErrorReportingLevel = error_reporting();
+            error_reporting($oldErrorReportingLevel & ~ E_DEPRECATED);
+
             require_once 'HTMLPurifier.autoload.php';
 
+            error_reporting($oldErrorReportingLevel);
+
             $config = HTMLPurifier_Config::createDefault();
             $config->set('Core.EscapeNonASCIICharacters', true);
             $config->set('HTML.Allowed', 'p,br,b,a[href|target],i,table,tr,th[colspan],td[colspan],div,*[class]');
diff --git a/modules/monitoring/library/Monitoring/Plugin.php b/modules/monitoring/library/Monitoring/Plugin.php
index 2edc459700..e8e1f5dbb8 100644
--- a/modules/monitoring/library/Monitoring/Plugin.php
+++ b/modules/monitoring/library/Monitoring/Plugin.php
@@ -3,6 +3,8 @@
 
 namespace Icinga\Module\Monitoring;
 
+use Icinga\Application\Cli;
+
 require_once ICINGA_LIBDIR . '/Icinga/Application/Cli.php';
 
 class Plugin extends Cli
diff --git a/modules/test/application/clicommands/PhpCommand.php b/modules/test/application/clicommands/PhpCommand.php
index 8a62deffd9..8e50d78c12 100644
--- a/modules/test/application/clicommands/PhpCommand.php
+++ b/modules/test/application/clicommands/PhpCommand.php
@@ -3,8 +3,11 @@
 
 namespace Icinga\Module\Test\Clicommands;
 
+use ErrorException;
 use Icinga\Application\Icinga;
 use Icinga\Cli\Command;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
 
 /**
  * PHP unit- & style-tests
@@ -68,7 +71,7 @@ public function unitAction()
             . $phpUnit
             . ' -c modules/test/phpunit.xml'
             . ' ' . join(' ', array_merge($options, $this->params->getAllStandalone()));
-        
+
         if ($this->isVerbose) {
             $res = `$command`;
             foreach (preg_split('/\n/', $res) as $line) {
@@ -155,6 +158,96 @@ public function styleAction()
         );
     }
 
+    /**
+     * Run code-validity checks
+     *
+     * This command checks whether icingaweb and installed modules match PHP syntax.
+     *
+     * USAGE
+     *
+     * icingacli test php validity
+     */
+    public function validityAction()
+    {
+        $types = array(
+            T_CLASS     => 'class',
+            T_INTERFACE => 'interface'
+        );
+
+        if (version_compare(PHP_VERSION, '5.4.0') > -1) {
+            $types[T_TRAIT] = 'trait';
+        }
+
+        $files = array();
+        $baseDir = realpath(__DIR__ . '/../../../..');
+        $iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($baseDir));
+
+        foreach ($iterator as $path => $info) {
+            /** @var \SplFileInfo $info */
+            if (preg_match(
+                '~\A(?:test|vendor|modules/[^/]+/test|library/Icinga/Test)(?:/|\z)~',
+                $iterator->getInnerIterator()->getSubPath()
+            ) || ! ($info->isFile() && preg_match('/\.php\z/', $path))) {
+                continue;
+            }
+
+            $content = file_get_contents("file://$path");
+            $lines = explode("\n", $content);
+            $tokens = token_get_all($content);
+            $lastDocComment = '';
+
+            foreach ($tokens as $token) {
+                if (! is_array($token)) {
+                    continue;
+                }
+
+                list($tokenNr, $raw, $lineNr) = $token;
+
+                if ($tokenNr === T_DOC_COMMENT) {
+                    $lastDocComment = $raw;
+                    continue;
+                }
+
+                if (array_key_exists($tokenNr, $types)) {
+                    $matches = array();
+                    if (preg_match('/\A\s*(\w+)\s+\w+/', $lines[$lineNr - 1], $matches)) {
+                        list($_, $type) = $matches;
+
+                        if ($type === $types[$tokenNr]) {
+                            // Valid definition header
+
+                            if (! preg_match('/@deprecated\b/', $lastDocComment)) {
+                                $files[] = $path;
+                            }
+                        }
+                    }
+
+                    // Bad definition header
+                    break;
+                }
+            }
+
+            // No definition header
+        }
+
+        define('ICINGA_LIBDIR', "$baseDir/library");
+
+        require_once 'HTMLPurifier/Bootstrap.php';
+        require_once 'HTMLPurifier.php';
+
+        $oldErrorReportingLevel = error_reporting();
+        error_reporting($oldErrorReportingLevel & ~ E_DEPRECATED);
+
+        require_once 'HTMLPurifier.autoload.php';
+
+        error_reporting($oldErrorReportingLevel);
+
+        foreach ($files as $file) {
+            printf('+ require_once %s;%s', var_export($file, true), PHP_EOL);
+            require_once $file;
+        }
+    }
+
     /**
      * Setup the directory where to put report files and return its path
      *
diff --git a/test/php/library/Icinga/Application/PhpCodeValidityTest.php b/test/php/library/Icinga/Application/PhpCodeValidityTest.php
new file mode 100644
index 0000000000..6a3ff3beb0
--- /dev/null
+++ b/test/php/library/Icinga/Application/PhpCodeValidityTest.php
@@ -0,0 +1,50 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Tests\Icinga\Application;
+
+use DirectoryIterator;
+use Icinga\Application\Config;
+use Icinga\Data\ConfigObject;
+use Icinga\File\Storage\TemporaryLocalFileStorage;
+use Icinga\Test\BaseTestCase;
+
+class PhpCodeValidityTest extends BaseTestCase
+{
+    /**
+     * Collect all classes, interfaces and traits and let PHP validate them as if included
+     */
+    public function testAllClassesInterfacesAndTraits()
+    {
+        $baseDir = realpath(__DIR__ . '/../../../../..');
+        $storage = new TemporaryLocalFileStorage();
+
+        $storage->create('etc/icingaweb2/config.ini', (string) new Config(new ConfigObject(array(
+            'global' => array(
+                'module_path'       => "$baseDir/modules",
+                'config_backend'    => 'ini'
+            )
+        ))));
+
+        $icingacli = 'ICINGAWEB_CONFIGDIR=' . $storage->resolvePath('etc/icingaweb2')
+            . ' ' . realpath('/proc/self/exe') . " $baseDir/bin/icingacli";
+
+        foreach (new DirectoryIterator("$baseDir/modules") as $module) {
+            if (! $module->isDot() && $module->isDir()) {
+                $this->system("$icingacli module enable {$module->getFilename()}");
+            }
+        }
+
+        $this->system("$icingacli test php validity");
+    }
+
+    protected function system($command)
+    {
+        echo "+ $command" . PHP_EOL;
+
+        $return = 127;
+        system($command, $return);
+
+        $this->assertSame(0, $return);
+    }
+}
diff --git a/test/php/library/Icinga/File/Storage/LocalFileStorageTest.php b/test/php/library/Icinga/File/Storage/LocalFileStorageTest.php
index 86ccc6f03c..5f104a50c4 100644
--- a/test/php/library/Icinga/File/Storage/LocalFileStorageTest.php
+++ b/test/php/library/Icinga/File/Storage/LocalFileStorageTest.php
@@ -11,10 +11,16 @@
 
 class LocalFileStorageTest extends BaseTestCase
 {
+    /**
+     * @var int
+     */
+    protected $oldErrorReportingLevel;
+
     public function __construct($name = null, array $data = array(), $dataName = '')
     {
         parent::__construct($name, $data, $dataName);
 
+        $this->oldErrorReportingLevel = error_reporting();
         error_reporting(E_ALL | E_STRICT);
 
         set_error_handler(function ($errno, $errstr, $errfile, $errline) {
@@ -35,6 +41,12 @@ public function __construct($name = null, array $data = array(), $dataName = '')
         });
     }
 
+    public function __destruct()
+    {
+        error_reporting($this->oldErrorReportingLevel);
+        restore_error_handler();
+    }
+
     public function testGetIterator()
     {
         $lfs = new TemporaryLocalFileStorage();
diff --git a/test/php/library/Icinga/Web/Session/PhpSessionTest.php b/test/php/library/Icinga/Web/Session/PhpSessionTest.php
index d835fb034c..224e984621 100644
--- a/test/php/library/Icinga/Web/Session/PhpSessionTest.php
+++ b/test/php/library/Icinga/Web/Session/PhpSessionTest.php
@@ -13,7 +13,7 @@ private function getSession()
         if (!is_writable('/tmp')) {
             $this->markTestSkipped('Could not write to session directory');
         }
-        return new PhpSession(
+        return PhpSession::create(
             array(
                 'use_cookies'   => false,
                 'save_path'     => '/tmp',