diff --git a/apps/dav/lib/Connector/Sabre/AnonymousOptionsPlugin.php b/apps/dav/lib/Connector/Sabre/AnonymousOptionsPlugin.php
index e0aa19c50b..de414e3aa2 100644
--- a/apps/dav/lib/Connector/Sabre/AnonymousOptionsPlugin.php
+++ b/apps/dav/lib/Connector/Sabre/AnonymousOptionsPlugin.php
@@ -53,7 +53,7 @@ class AnonymousOptionsPlugin extends ServerPlugin {
 	 * @return bool
 	 */
 	public function isRequestInRoot($path) {
-		return $path === '' || (is_string($path) && strpos($path, '/') === FALSE);
+		return $path === '' || (is_string($path) && strpos($path, '/') === false);
 	}
 
 	/**
diff --git a/apps/dav/lib/Connector/Sabre/FilesPlugin.php b/apps/dav/lib/Connector/Sabre/FilesPlugin.php
index 459d2ffa32..498058f7c0 100644
--- a/apps/dav/lib/Connector/Sabre/FilesPlugin.php
+++ b/apps/dav/lib/Connector/Sabre/FilesPlugin.php
@@ -397,7 +397,7 @@ class FilesPlugin extends ServerPlugin {
 
 			$propFind->handle(self::CHECKSUMS_PROPERTYNAME, function() use ($node) {
 				$checksum = $node->getChecksum();
-				if ($checksum === NULL || $checksum === '') {
+				if ($checksum === null || $checksum === '') {
 					return null;
 				}
 
diff --git a/build/integration/features/bootstrap/Sharing.php b/build/integration/features/bootstrap/Sharing.php
index 66b1543643..3d6ca27f2a 100644
--- a/build/integration/features/bootstrap/Sharing.php
+++ b/build/integration/features/bootstrap/Sharing.php
@@ -327,14 +327,14 @@ trait Sharing {
 					return $this->isExpectedUrl((string)$element->$field, "index.php/s/");
 				}
 				elseif ((string)$element->$field == $contentExpected){
-					return True;
+					return true;
 				}
 				else{
 					print($element->$field);
 				}
 			}
 
-			return False;
+			return false;
 		} else {
 			if ($contentExpected == "A_TOKEN"){
 					return (strlen((string)$data->$field) == 15);
@@ -346,9 +346,9 @@ trait Sharing {
 					return $this->isExpectedUrl((string)$data->$field, "index.php/s/");
 			}
 			elseif ($data->$field == $contentExpected){
-					return True;
+					return true;
 			}
-			return False;
+			return false;
 		}
 	}
 
@@ -358,7 +358,7 @@ trait Sharing {
 	 * @param string $filename
 	 */
 	public function checkSharedFileInResponse($filename){
-		Assert::assertEquals(True, $this->isFieldInResponse('file_target', "/$filename"));
+		Assert::assertEquals(true, $this->isFieldInResponse('file_target', "/$filename"));
 	}
 
 	/**
@@ -367,7 +367,7 @@ trait Sharing {
 	 * @param string $filename
 	 */
 	public function checkSharedFileNotInResponse($filename){
-		Assert::assertEquals(False, $this->isFieldInResponse('file_target', "/$filename"));
+		Assert::assertEquals(false, $this->isFieldInResponse('file_target', "/$filename"));
 	}
 
 	/**
@@ -376,7 +376,7 @@ trait Sharing {
 	 * @param string $user
 	 */
 	public function checkSharedUserInResponse($user){
-		Assert::assertEquals(True, $this->isFieldInResponse('share_with', "$user"));
+		Assert::assertEquals(true, $this->isFieldInResponse('share_with', "$user"));
 	}
 
 	/**
@@ -385,17 +385,17 @@ trait Sharing {
 	 * @param string $user
 	 */
 	public function checkSharedUserNotInResponse($user){
-		Assert::assertEquals(False, $this->isFieldInResponse('share_with', "$user"));
+		Assert::assertEquals(false, $this->isFieldInResponse('share_with', "$user"));
 	}
 
 	public function isUserOrGroupInSharedData($userOrGroup, $permissions = null){
 		$data = simplexml_load_string($this->response->getBody())->data[0];
 		foreach($data as $element) {
 			if ($element->share_with == $userOrGroup && ($permissions === null || $permissions == $element->permissions)){
-				return True;
+				return true;
 			}
 		}
-		return False;
+		return false;
 	}
 
 	/**
@@ -424,7 +424,7 @@ trait Sharing {
 			$this->createShare($user1, $filepath, 0, $user2, null, null, $permissions);
 		}
 		$this->response = $client->get($fullUrl, $options);
-		Assert::assertEquals(True, $this->isUserOrGroupInSharedData($user2, $permissions));
+		Assert::assertEquals(true, $this->isUserOrGroupInSharedData($user2, $permissions));
 	}
 
 	/**
@@ -453,7 +453,7 @@ trait Sharing {
 			$this->createShare($user, $filepath, 1, $group, null, null, $permissions);
 		}
 		$this->response = $client->get($fullUrl, $options);
-		Assert::assertEquals(True, $this->isUserOrGroupInSharedData($group, $permissions));
+		Assert::assertEquals(true, $this->isUserOrGroupInSharedData($group, $permissions));
 	}
 
 	/**
diff --git a/lib/private/Contacts/ContactsMenu/ContactsStore.php b/lib/private/Contacts/ContactsMenu/ContactsStore.php
index 9efa42b9a4..9dfc803c49 100644
--- a/lib/private/Contacts/ContactsMenu/ContactsStore.php
+++ b/lib/private/Contacts/ContactsMenu/ContactsStore.php
@@ -159,7 +159,7 @@ class ContactsStore implements IContactsStore {
 			if ($ownGroupsOnly && $entry->getProperty('isLocalSystemBook') === true) {
 				$uid = $this->userManager->get($entry->getProperty('UID'));
 
-				if ($uid === NULL) {
+				if ($uid === null) {
 					return false;
 				}
 
diff --git a/lib/private/Files/Cache/Wrapper/CacheJail.php b/lib/private/Files/Cache/Wrapper/CacheJail.php
index 6f951f978a..92601e38d1 100644
--- a/lib/private/Files/Cache/Wrapper/CacheJail.php
+++ b/lib/private/Files/Cache/Wrapper/CacheJail.php
@@ -241,7 +241,7 @@ class CacheJail extends CacheWrapper {
 		$results = $this->getCache()->searchQuery($simpleQuery);
 		$results = $this->formatSearchResults($results);
 
-		$limit = $query->getLimit() === 0 ? NULL : $query->getLimit();
+		$limit = $query->getLimit() === 0 ? null : $query->getLimit();
 		$results = array_slice($results, $query->getOffset(), $limit);
 
 		return $results;
diff --git a/lib/private/Template/JSCombiner.php b/lib/private/Template/JSCombiner.php
index a6908ce807..83fc717c9c 100644
--- a/lib/private/Template/JSCombiner.php
+++ b/lib/private/Template/JSCombiner.php
@@ -133,7 +133,7 @@ class JSCombiner {
 
 			$deps = json_decode($deps, true);
 
-			if ($deps === NULL) {
+			if ($deps === null) {
 				return false;
 			}
 
diff --git a/lib/private/legacy/util.php b/lib/private/legacy/util.php
index bf0a1b9bb2..63edf34e02 100644
--- a/lib/private/legacy/util.php
+++ b/lib/private/legacy/util.php
@@ -795,7 +795,7 @@ class OC_Util {
 				// is_writable doesn't work for NFS mounts, so try to write a file and check if it exists.
 				$testFile = sprintf('%s/%s.tmp', $CONFIG_DATADIRECTORY, uniqid('data_dir_writability_test_'));
 				$handle = fopen($testFile, 'w');
-				if (!$handle || fwrite($handle, 'Test write operation') === FALSE) {
+				if (!$handle || fwrite($handle, 'Test write operation') === false) {
 					$permissionsHint = $l->t('Permissions can usually be fixed by giving the webserver write access to the root directory. See %s.',
 						[$urlGenerator->linkToDocs('admin-dir_permissions')]);
 					$errors[] = [
diff --git a/lib/public/Util.php b/lib/public/Util.php
index 544808f5ec..74a4b18f5d 100644
--- a/lib/public/Util.php
+++ b/lib/public/Util.php
@@ -260,7 +260,7 @@ class Util {
 		$host_name = \OC::$server->getRequest()->getServerHost();
 		// strip away port number (if existing)
 		$colon_pos = strpos($host_name, ':');
-		if ($colon_pos != FALSE) {
+		if ($colon_pos != false) {
 			$host_name = substr($host_name, 0, $colon_pos);
 		}
 		return $host_name;
diff --git a/tests/lib/Avatar/UserAvatarTest.php b/tests/lib/Avatar/UserAvatarTest.php
index 43e325b094..ed0a32dab6 100644
--- a/tests/lib/Avatar/UserAvatarTest.php
+++ b/tests/lib/Avatar/UserAvatarTest.php
@@ -70,7 +70,7 @@ class UserAvatarTest extends \Test\TestCase {
 				return false;
 			}));
 
-		$data = NULL;
+		$data = null;
 		$file->method('putContent')
 			->with($this->callback(function ($d) use (&$data) {
 				$data = $d;
diff --git a/tests/lib/DB/LegacyDBTest.php b/tests/lib/DB/LegacyDBTest.php
index 200afac3f9..ce7ef0a3a6 100644
--- a/tests/lib/DB/LegacyDBTest.php
+++ b/tests/lib/DB/LegacyDBTest.php
@@ -16,7 +16,7 @@ use OC_DB;
  * @group DB
  */
 class LegacyDBTest extends \Test\TestCase {
-	protected $backupGlobals = FALSE;
+	protected $backupGlobals = false;
 
 	protected static $schema_file;
 	protected $test_prefix;
diff --git a/tests/lib/Files/Stream/EncryptionTest.php b/tests/lib/Files/Stream/EncryptionTest.php
index fd5e8c6ca9..e2213365d5 100644
--- a/tests/lib/Files/Stream/EncryptionTest.php
+++ b/tests/lib/Files/Stream/EncryptionTest.php
@@ -205,9 +205,9 @@ class EncryptionTest extends \Test\TestCase {
 		$fileName = tempnam("/tmp", "FOO");
 		$stream = $this->getStream($fileName, 'w+', 0);
 		$this->assertEquals(6, fwrite($stream, 'foobar'));
-		$this->assertEquals(TRUE, rewind($stream));
+		$this->assertEquals(true, rewind($stream));
 		$this->assertEquals('foobar', fread($stream, 100));
-		$this->assertEquals(TRUE, rewind($stream));
+		$this->assertEquals(true, rewind($stream));
 		$this->assertEquals(3, fwrite($stream, 'bar'));
 		fclose($stream);
 
diff --git a/tests/lib/Mail/MessageTest.php b/tests/lib/Mail/MessageTest.php
index ab62cfcfdc..4d61504cd9 100644
--- a/tests/lib/Mail/MessageTest.php
+++ b/tests/lib/Mail/MessageTest.php
@@ -36,7 +36,7 @@ class MessageTest extends TestCase {
 	 */
 	public function getMailAddressProvider() {
 		return array(
-			array(NULL, array()),
+			array(null, array()),
 			array(array('lukas@owncloud.com' => 'Lukas Reschke'), array('lukas@owncloud.com' => 'Lukas Reschke')),
 		);
 	}
diff --git a/tests/lib/TagsTest.php b/tests/lib/TagsTest.php
index db0a77f68f..ab717b4cc2 100644
--- a/tests/lib/TagsTest.php
+++ b/tests/lib/TagsTest.php
@@ -36,7 +36,7 @@ class TagsTest extends \Test\TestCase {
 	protected $user;
 	/** @var \OCP\IUserSession */
 	protected $userSession;
-	protected $backupGlobals = FALSE;
+	protected $backupGlobals = false;
 	/** @var \OC\Tagging\TagMapper */
 	protected $tagMapper;
 	/** @var \OCP\ITagManager */