diff --git a/.gitattributes b/.gitattributes
index 4be1c91852..18ba9e0758 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,2 +1,2 @@
-# Disable LF normalization for all files
-* -text
\ No newline at end of file
+# Disable LF normalization for all files
+* -text
diff --git a/.gitignore b/.gitignore
index 9e6504184c..12dd3b49ea 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,61 +1,67 @@
-favicon.*
-.htconfig.php
-.htpreconfig.php
-\#*
-include/jquery-1.4.2.min.js
-*.log
-*.out
-*.version*
-favicon.*
-home.html
-addon
-*.orig
-*~
-robots.txt
-
-#ignore documentation, it should be newly built
-doc/html
-
-#ignore reports, should be generted with every build
-report/
-
-#ignore config files from eclipse, we don't want IDE files in our repository
-.project
-.buildpath
-.externalToolBuilders
-.settings
-#ignore OSX .DS_Store files
-.DS_Store
-
-/nbproject/private/
-
-#ignore smarty cache
-/view/smarty3/compiled/
-
-#ignore cache folders
-/privacy_image_cache/
-/photo/
-/proxy/
-nbproject
-
-#ignore vagrant dir
-.vagrant/
-
-#ignore local folder
-/local/
-
-#ignore config files from Visual Studio
-/.vs/
-/php_friendica.phpproj
-/php_friendica.sln
-/php_friendica.phpproj.user
-
-#ignore things from transifex-client
-venv/
-
-#ignore Composer dependencies
-/vendor
-/view/asset
-
-#ignore config files from JetBrains
-/.idea
+favicon.*
+.htconfig.php
+.htpreconfig.php
+\#*
+include/jquery-1.4.2.min.js
+*.log
+*.out
+*.version*
+favicon.*
+home.html
+addon
+*~
+robots.txt
+
+#ignore documentation, it should be newly built
+doc/html
+
+#ignore reports, should be generted with every build
+report/
+
+#ignore config files from eclipse, we don't want IDE files in our repository
+.project
+.buildpath
+.externalToolBuilders
+.settings
+
+#ignore OSX .DS_Store files
+.DS_Store
+
+#ignore NetBeans IDE's private files (at least)
+/nbproject/private/
+
+#ignore smarty cache
+/view/smarty3/compiled/
+
+#ignore cache folders
+/privacy_image_cache/
+/photo/
+/proxy/
+nbproject
+
+#ignore vagrant dir
+.vagrant/
+
+#ignore local folder
+/local/
+
+#ignore config files from Visual Studio
+/.vs/
+/php_friendica.phpproj
+/php_friendica.sln
+/php_friendica.phpproj.user
+
+#ignore things from transifex-client
+venv/
+
+#ignore all in 'vendor' as `utils/composer.phar install` will bring it back
+vendor/*
+
+#ignore config files from JetBrains
+/.idea
+
+#ignore addons/ directory
+addons/
+
+#Ignore .htaccess as it may contain local changes
+.htaccess
diff --git a/.htaccess b/.htaccess-dist
similarity index 96%
rename from .htaccess
rename to .htaccess-dist
index 2348cdc38b..a671cc680a 100644
--- a/.htaccess
+++ b/.htaccess-dist
@@ -4,7 +4,7 @@ AddType audio/ogg .oga
 #AddHandler php53-cgi .php
 
 <FilesMatch "\.(out|log)$">
-  <IfModule authz_host_module> 
+  <IfModule authz_host_module>
     #Apache 2.4
     Require all denied
   </IfModule>
@@ -38,4 +38,3 @@ AddType audio/ogg .oga
   RewriteRule ^(.*)$ index.php?pagename=$1 [E=REMOTE_USER:%{HTTP:Authorization},L,QSA]
 
 </IfModule>
-
diff --git a/bin/daemon.php b/bin/daemon.php
index 6b0e377a3a..b51dd392ef 100755
--- a/bin/daemon.php
+++ b/bin/daemon.php
@@ -38,7 +38,7 @@ if (substr($directory, 0, 1) != "/") {
 }
 $directory = realpath($directory."/..");
 
-@include($directory."/.htconfig.php");
+include $directory."/.htconfig.php";
 
 if (!isset($pidfile)) {
 	die('Please specify a pid file in the variable $pidfile in the .htconfig.php. For example:'."\n".
diff --git a/boot.php b/boot.php
index ae2f4b1a06..6945026012 100644
--- a/boot.php
+++ b/boot.php
@@ -1076,6 +1076,7 @@ function is_site_admin()
 	$adminlist = explode(",", str_replace(" ", "", $a->config['admin_email']));
 
 	//if(local_user() && x($a->user,'email') && x($a->config,'admin_email') && ($a->user['email'] === $a->config['admin_email']))
+	/// @TODO This if() + 2 returns can be shrinked into one return
 	if (local_user() && x($a->user, 'email') && x($a->config, 'admin_email') && in_array($a->user['email'], $adminlist)) {
 		return true;
 	}
@@ -1173,7 +1174,7 @@ function random_digits($digits)
 {
 	$rn = '';
 	for ($i = 0; $i < $digits; $i++) {
-		/// @TODO rand() is different to mt_rand() and maybe lesser "random"
+		/// @TODO Avoid rand/mt_rand, when it comes to cryptography, they are generating predictable (seedable) numbers.
 		$rn .= rand(0, 9);
 	}
 	return $rn;
@@ -1187,7 +1188,7 @@ function get_server()
 		$server = "https://dir.friendica.social";
 	}
 
-	return($server);
+	return $server;
 }
 
 function get_temppath()
@@ -1236,7 +1237,7 @@ function get_cachefile($file, $writemode = true)
 	$cache = get_itemcachepath();
 
 	if ((!$cache) || (!is_dir($cache))) {
-		return("");
+		return "";
 	}
 
 	$subfolder = $cache . "/" . substr($file, 0, 2);
@@ -1250,7 +1251,6 @@ function get_cachefile($file, $writemode = true)
 		}
 	}
 
-	/// @TODO no need to put braces here
 	return $cachepath;
 }
 
@@ -1357,7 +1357,6 @@ function get_spoolpath()
 	return "";
 }
 
-
 if (!function_exists('exif_imagetype')) {
 	function exif_imagetype($file)
 	{
@@ -1395,7 +1394,7 @@ function validate_include(&$file)
 	}
 
 	// Simply return flag
-	return ($valid);
+	return $valid;
 }
 
 function current_load()
diff --git a/mods/readme.txt b/doc/server-config/readme.txt
similarity index 100%
rename from mods/readme.txt
rename to doc/server-config/readme.txt
diff --git a/mods/sample-Lighttpd.config b/doc/server-config/sample-Lighttpd.config
similarity index 100%
rename from mods/sample-Lighttpd.config
rename to doc/server-config/sample-Lighttpd.config
diff --git a/mods/sample-nginx-reverse-proxy.config b/doc/server-config/sample-nginx-reverse-proxy.config
similarity index 100%
rename from mods/sample-nginx-reverse-proxy.config
rename to doc/server-config/sample-nginx-reverse-proxy.config
diff --git a/mods/sample-nginx.config b/doc/server-config/sample-nginx.config
similarity index 100%
rename from mods/sample-nginx.config
rename to doc/server-config/sample-nginx.config
diff --git a/include/api.php b/include/api.php
index 72997dd3a0..ae2f06406e 100644
--- a/include/api.php
+++ b/include/api.php
@@ -935,7 +935,7 @@ function api_reformat_xml(&$item, &$key)
  *
  * @return string The XML data
  */
-function api_create_xml($data, $root_element)
+function api_create_xml(array $data, $root_element)
 {
 	$childname = key($data);
 	$data2 = array_pop($data);
@@ -960,7 +960,7 @@ function api_create_xml($data, $root_element)
 		$i = 1;
 
 		foreach ($data2 as $item) {
-			$data4[$i++.":".$childname] = $item;
+			$data4[$i++ . ":" . $childname] = $item;
 		}
 
 		$data2 = $data4;
@@ -4379,7 +4379,6 @@ function api_fr_photo_create_update($type)
 	throw new InternalServerErrorException("unknown error - this error on uploading or updating a photo should never happen");
 }
 
-
 /**
  * @brief delete a single photo from the database through api
  *
@@ -4518,6 +4517,7 @@ function api_account_update_profile_image($type)
 	} else {
 		throw new InternalServerErrorException('Unsupported filetype');
 	}
+
 	// change specified profile or all profiles to the new resource-id
 	if ($is_default_profile) {
 		$condition = ["`profile` AND `resource-id` != ? AND `uid` = ?", $data['photo']['id'], api_user()];
@@ -4531,7 +4531,6 @@ function api_account_update_profile_image($type)
 	Contact::updateSelfFromUserID(api_user(), true);
 
 	// Update global directory in background
-	//$user = api_get_user(get_app());
 	$url = System::baseUrl() . '/profile/' . get_app()->user['nickname'];
 	if ($url && strlen(Config::get('system', 'directory'))) {
 		Worker::add(PRIORITY_LOW, "Directory", $url);
@@ -5273,27 +5272,27 @@ function api_in_reply_to($item)
 
 /**
  *
- * @param string $Text
+ * @param string $text
  *
  * @return string
  */
-function api_clean_plain_items($Text)
+function api_clean_plain_items($text)
 {
 	$include_entities = strtolower(x($_REQUEST, 'include_entities') ? $_REQUEST['include_entities'] : "false");
 
-	$Text = BBCode::cleanPictureLinks($Text);
+	$text = BBCode::cleanPictureLinks($text);
 	$URLSearchString = "^\[\]";
 
-	$Text = preg_replace("/([!#@])\[url\=([$URLSearchString]*)\](.*?)\[\/url\]/ism", '$1$3', $Text);
+	$text = preg_replace("/([!#@])\[url\=([$URLSearchString]*)\](.*?)\[\/url\]/ism", '$1$3', $text);
 
 	if ($include_entities == "true") {
-		$Text = preg_replace("/\[url\=([$URLSearchString]*)\](.*?)\[\/url\]/ism", '[url=$1]$1[/url]', $Text);
+		$text = preg_replace("/\[url\=([$URLSearchString]*)\](.*?)\[\/url\]/ism", '[url=$1]$1[/url]', $text);
 	}
 
 	// Simplify "attachment" element
-	$Text = api_clean_attachments($Text);
+	$text = api_clean_attachments($text);
 
-	return($Text);
+	return $text;
 }
 
 /**
diff --git a/include/conversation.php b/include/conversation.php
index ae12cf4827..43f0a445da 100644
--- a/include/conversation.php
+++ b/include/conversation.php
@@ -116,7 +116,7 @@ function localize_item(&$item) {
 		$item['body'] = item_redir_and_replace_images($extracted['body'], $extracted['images'], $item['contact-id']);
 	}
 
-	/// @Separted ???
+	/// @TODO Separted ???
 	$xmlhead = "<" . "?xml version='1.0' encoding='UTF-8' ?" . ">";
 	if (activity_match($item['verb'], ACTIVITY_LIKE)
 		|| activity_match($item['verb'], ACTIVITY_DISLIKE)
@@ -162,22 +162,19 @@ function localize_item(&$item) {
 
 		if (activity_match($item['verb'], ACTIVITY_LIKE)) {
 			$bodyverb = L10n::t('%1$s likes %2$s\'s %3$s');
-		}
-		elseif (activity_match($item['verb'], ACTIVITY_DISLIKE)) {
+		} elseif (activity_match($item['verb'], ACTIVITY_DISLIKE)) {
 			$bodyverb = L10n::t('%1$s doesn\'t like %2$s\'s %3$s');
-		}
-		elseif (activity_match($item['verb'], ACTIVITY_ATTEND)) {
+		} elseif (activity_match($item['verb'], ACTIVITY_ATTEND)) {
 			$bodyverb = L10n::t('%1$s attends %2$s\'s %3$s');
-		}
-		elseif (activity_match($item['verb'], ACTIVITY_ATTENDNO)) {
+		} elseif (activity_match($item['verb'], ACTIVITY_ATTENDNO)) {
 			$bodyverb = L10n::t('%1$s doesn\'t attend %2$s\'s %3$s');
-		}
-		elseif (activity_match($item['verb'], ACTIVITY_ATTENDMAYBE)) {
+		} elseif (activity_match($item['verb'], ACTIVITY_ATTENDMAYBE)) {
 			$bodyverb = L10n::t('%1$s attends maybe %2$s\'s %3$s');
 		}
-		$item['body'] = sprintf($bodyverb, $author, $objauthor, $plink);
 
+		$item['body'] = sprintf($bodyverb, $author, $objauthor, $plink);
 	}
+
 	if (activity_match($item['verb'], ACTIVITY_FRIEND)) {
 
 		if ($item['object-type']=="" || $item['object-type']!== ACTIVITY_OBJ_PERSON) return;
@@ -304,8 +301,8 @@ function localize_item(&$item) {
 		$item['body'] = L10n::t('%1$s tagged %2$s\'s %3$s with %4$s', $author, $objauthor, $plink, $tag );
 
 	}
-	if (activity_match($item['verb'], ACTIVITY_FAVORITE)) {
 
+	if (activity_match($item['verb'], ACTIVITY_FAVORITE)) {
 		if ($item['object-type'] == "") {
 			return;
 		}
@@ -394,10 +391,9 @@ function visible_activity($item) {
 		}
 	}
 
-	if (activity_match($item['verb'], ACTIVITY_FOLLOW) && $item['object-type'] === ACTIVITY_OBJ_NOTE) {
-		if (!($item['self'] && ($item['uid'] == local_user()))) {
-			return false;
-		}
+	// @TODO below if() block can be rewritten to a single line: $isVisible = allConditionsHere;
+	if (activity_match($item['verb'], ACTIVITY_FOLLOW) && $item['object-type'] === ACTIVITY_OBJ_NOTE && empty($item['self']) && $item['uid'] == local_user()) {
+		return false;
 	}
 
 	return true;
@@ -1123,7 +1119,7 @@ function builtin_activity_puller($item, &$conv_responses) {
 
 			$url = '<a href="'. $url . '"'. $sparkle .'>' . htmlentities($item['author-name']) . '</a>';
 
-			if (!$item['thr-parent']) {
+			if (!x($item, 'thr-parent')) {
 				$item['thr-parent'] = $item['parent-uri'];
 			}
 
@@ -1611,19 +1607,17 @@ function sort_thr_commented(array $a, array $b)
 	return strcmp($b['commented'], $a['commented']);
 }
 
-/// @TODO Add type-hint
-function render_location_dummy($item) {
-	if ($item['location'] != "") {
+function render_location_dummy(array $item) {
+	if (x($item, 'location') && !empty($item['location'])) {
 		return $item['location'];
 	}
 
-	if ($item['coord'] != "") {
+	if (x($item, 'coord') && !empty($item['coord'])) {
 		return $item['coord'];
 	}
 }
 
-/// @TODO Add type-hint
-function get_responses($conv_responses, $response_verbs, $ob, $item) {
+function get_responses(array $conv_responses, array $response_verbs, $ob, array $item) {
 	$ret = [];
 	foreach ($response_verbs as $v) {
 		$ret[$v] = [];
diff --git a/include/items.php b/include/items.php
index af13898b24..1cfad356c2 100644
--- a/include/items.php
+++ b/include/items.php
@@ -274,6 +274,7 @@ function consume_feed($xml, $importer, $contact, &$hub, $datedir = 0, $pass = 0)
 function subscribe_to_hub($url, $importer, $contact, $hubmode = 'subscribe') {
 
 	$a = get_app();
+	$r = null;
 
 	if (is_array($importer)) {
 		$r = q("SELECT `nickname` FROM `user` WHERE `uid` = %d LIMIT 1",
diff --git a/include/security.php b/include/security.php
index b13a507cf4..bcfddf8872 100644
--- a/include/security.php
+++ b/include/security.php
@@ -254,6 +254,7 @@ function can_write_wall($owner)
 	return false;
 }
 
+/// @TODO $groups should be array
 function permissions_sql($owner_id, $remote_verified = false, $groups = null)
 {
 	$local_user = local_user();
@@ -275,6 +276,13 @@ function permissions_sql($owner_id, $remote_verified = false, $groups = null)
 	 */
 	if ($local_user && $local_user == $owner_id) {
 		$sql = '';
+	/**
+	 * Authenticated visitor. Unless pre-verified,
+	 * check that the contact belongs to this $owner_id
+	 * and load the groups the visitor belongs to.
+	 * If pre-verified, the caller is expected to have already
+	 * done this and passed the groups into this function.
+	 */
 	} elseif ($remote_user) {
 		/*
 		 * Authenticated visitor. Unless pre-verified,
@@ -298,9 +306,10 @@ function permissions_sql($owner_id, $remote_verified = false, $groups = null)
 		if ($remote_verified) {
 			$gs = '<<>>'; // should be impossible to match
 
-			if (is_array($groups) && count($groups)) {
-				foreach ($groups as $g)
+			if (is_array($groups)) {
+				foreach ($groups as $g) {
 					$gs .= '|<' . intval($g) . '>';
+				}
 			}
 
 			$sql = sprintf(
diff --git a/include/text.php b/include/text.php
index 4c9a8864d5..3f66d379c9 100644
--- a/include/text.php
+++ b/include/text.php
@@ -182,6 +182,7 @@ function autoname($len) {
 			break;
 		}
 	}
+
 	if (substr($word, -1) == 'q') {
 		$word = substr($word, 0, -1);
 	}
@@ -452,7 +453,7 @@ function perms2str($p) {
 	if (is_array($p)) {
 		$tmp = $p;
 	} else {
-		$tmp = explode(',',$p);
+		$tmp = explode(',', $p);
 	}
 
 	if (is_array($tmp)) {
@@ -1660,10 +1661,11 @@ function bb_translate_video($s) {
 	$r = preg_match_all("/\[video\](.*?)\[\/video\]/ism",$s,$matches,PREG_SET_ORDER);
 	if ($r) {
 		foreach ($matches as $mtch) {
-			if ((stristr($mtch[1],'youtube')) || (stristr($mtch[1],'youtu.be')))
-				$s = str_replace($mtch[0],'[youtube]' . $mtch[1] . '[/youtube]',$s);
-			elseif (stristr($mtch[1],'vimeo'))
-				$s = str_replace($mtch[0],'[vimeo]' . $mtch[1] . '[/vimeo]',$s);
+			if ((stristr($mtch[1], 'youtube')) || (stristr($mtch[1], 'youtu.be'))) {
+				$s = str_replace($mtch[0], '[youtube]' . $mtch[1] . '[/youtube]', $s);
+			} elseif (stristr($mtch[1], 'vimeo')) {
+				$s = str_replace($mtch[0], '[vimeo]' . $mtch[1] . '[/vimeo]', $s);
+			}
 		}
 	}
 	return $s;
@@ -1781,7 +1783,7 @@ function file_tag_file_query($table,$s,$type = 'file') {
 }
 
 // ex. given music,video return <music><video> or [music][video]
-function file_tag_list_to_file($list,$type = 'file') {
+function file_tag_list_to_file($list, $type = 'file') {
 	$tag_list = '';
 	if (strlen($list)) {
 		$list_array = explode(",",$list);
@@ -1803,7 +1805,7 @@ function file_tag_list_to_file($list,$type = 'file') {
 }
 
 // ex. given <music><video>[friends], return music,video or friends
-function file_tag_file_to_list($file,$type = 'file') {
+function file_tag_file_to_list($file, $type = 'file') {
 	$matches = false;
 	$list = '';
 	if ($type == 'file') {
@@ -1829,8 +1831,7 @@ function file_tag_update_pconfig($uid, $file_old, $file_new, $type = 'file') {
 
 	if (!intval($uid)) {
 		return false;
-	}
-	if ($file_old == $file_new) {
+	} elseif ($file_old == $file_new) {
 		return true;
 	}
 
@@ -1853,8 +1854,9 @@ function file_tag_update_pconfig($uid, $file_old, $file_new, $type = 'file') {
 		$check_new_tags = explode(",",file_tag_file_to_list($file_new,$type));
 
 		foreach ($check_new_tags as $tag) {
-			if (! stristr($saved,$lbracket . file_tag_encode($tag) . $rbracket))
+			if (! stristr($saved,$lbracket . file_tag_encode($tag) . $rbracket)) {
 				$new_tags[] = $tag;
+			}
 		}
 
 		$filetags_updated .= file_tag_list_to_file(implode(",",$new_tags),$type);
@@ -1864,8 +1866,9 @@ function file_tag_update_pconfig($uid, $file_old, $file_new, $type = 'file') {
 		$check_deleted_tags = explode(",",file_tag_file_to_list($file_old,$type));
 
 		foreach ($check_deleted_tags as $tag) {
-			if (! stristr($file_new,$lbracket . file_tag_encode($tag) . $rbracket))
+			if (! stristr($file_new,$lbracket . file_tag_encode($tag) . $rbracket)) {
 				$deleted_tags[] = $tag;
+			}
 		}
 
 		foreach ($deleted_tags as $key => $tag) {
@@ -1975,17 +1978,22 @@ function protect_sprintf($s) {
 	return str_replace('%', '%%', $s);
 }
 
-
+/// @TODO Rewrite this
 function is_a_date_arg($s) {
 	$i = intval($s);
+
 	if ($i > 1900) {
 		$y = date('Y');
+
 		if ($i <= $y + 1 && strpos($s, '-') == 4) {
-			$m = intval(substr($s,5));
-			if ($m > 0 && $m <= 12)
+			$m = intval(substr($s, 5));
+
+			if ($m > 0 && $m <= 12) {
 				return true;
+			}
 		}
 	}
+
 	return false;
 }
 
@@ -2003,6 +2011,7 @@ function deindent($text, $chr = "[\t ]", $count = NULL) {
 		preg_match("|^" . $chr . "*|", $lines[$k], $m);
 		$count = strlen($m[0]);
 	}
+
 	for ($k = 0; $k < count($lines); $k++) {
 		$lines[$k] = preg_replace("|^" . $chr . "{" . $count . "}|", "", $lines[$k]);
 	}
diff --git a/mod/admin.php b/mod/admin.php
index 39416dae54..1d6f1395a0 100644
--- a/mod/admin.php
+++ b/mod/admin.php
@@ -64,7 +64,7 @@ function admin_post(App $a)
 			case 'addons':
 				if ($a->argc > 2 &&
 					is_file("addon/" . $a->argv[2] . "/" . $a->argv[2] . ".php")) {
-					@include_once("addon/" . $a->argv[2] . "/" . $a->argv[2] . ".php");
+					include_once "addon/" . $a->argv[2] . "/" . $a->argv[2] . ".php";
 					if (function_exists($a->argv[2] . '_addon_admin_post')) {
 						$func = $a->argv[2] . '_addon_admin_post';
 						$func($a);
@@ -917,6 +917,7 @@ function admin_page_site_post(App $a)
 			$upds = implode(", ", $upd);
 
 			$r = q("UPDATE %s SET %s;", $table_name, $upds);
+
 			if (!DBM::is_result($r)) {
 				notice("Failed updating '$table_name': " . dba::errorMessage());
 				goaway('admin/site');
@@ -1298,15 +1299,18 @@ function admin_page_site(App $a)
 	$user_names = [];
 	$user_names['---'] = L10n::t('Multi user instance');
 	$users = q("SELECT `username`, `nickname` FROM `user`");
+
 	foreach ($users as $user) {
 		$user_names[$user['nickname']] = $user['username'];
 	}
 
 	/* Banner */
 	$banner = Config::get('system', 'banner');
+
 	if ($banner == false) {
 		$banner = '<a href="https://friendi.ca"><img id="logo-img" src="images/friendica-32.png" alt="logo" /></a><span id="logo-text"><a href="https://friendi.ca">Friendica</a></span>';
 	}
+
 	$banner = htmlspecialchars($banner);
 	$info = Config::get('config', 'info');
 	$info = htmlspecialchars($info);
@@ -1506,9 +1510,12 @@ function admin_page_dbsync(App $a)
 
 	if ($a->argc > 2 && intval($a->argv[2])) {
 		require_once 'update.php';
+
 		$func = 'update_' . intval($a->argv[2]);
+
 		if (function_exists($func)) {
 			$retval = $func();
+
 			if ($retval === UPDATE_FAILED) {
 				$o .= L10n::t("Executing %s failed with error: %s", $func, $retval);
 			} elseif ($retval === UPDATE_SUCCESS) {
@@ -1521,11 +1528,13 @@ function admin_page_dbsync(App $a)
 			$o .= L10n::t('There was no additional update function %s that needed to be called.', $func) . "<br />";
 			Config::set('database', $func, 'success');
 		}
+
 		return $o;
 	}
 
 	$failed = [];
 	$r = q("SELECT `k`, `v` FROM `config` WHERE `cat` = 'database' ");
+
 	if (DBM::is_result($r)) {
 		foreach ($r as $rr) {
 			$upd = intval(substr($rr['k'], 7));
@@ -1535,6 +1544,7 @@ function admin_page_dbsync(App $a)
 			$failed[] = $upd;
 		}
 	}
+
 	if (!count($failed)) {
 		$o = replace_macros(get_markup_template('structure_check.tpl'), [
 			'$base' => System::baseUrl(true),
@@ -1769,8 +1779,8 @@ function admin_page_users(App $a)
 		$e['page-flags-raw'] = $e['page-flags'];
 		$e['page-flags'] = $page_types[$e['page-flags']];
 
-		$e['account-type-raw'] = ($e['page_flags_raw']==0) ? $e['account-type'] : -1;
-		$e['account-type'] = ($e['page_flags_raw']==0) ? $account_types[$e['account-type']] : "";
+		$e['account-type-raw'] = ($e['page_flags_raw'] == 0) ? $e['account-type'] : -1;
+		$e['account-type'] = ($e['page_flags_raw'] == 0) ? $account_types[$e['account-type']] : "";
 
 		$e['register_date'] = Temporal::getRelativeDate($e['register_date']);
 		$e['login_date'] = Temporal::getRelativeDate($e['login_date']);
@@ -1921,7 +1931,7 @@ function admin_page_addons(App $a)
 
 		$admin_form = "";
 		if (in_array($addon, $a->addons_admin)) {
-			@require_once("addon/$addon/$addon.php");
+			require_once "addon/$addon/$addon.php";
 			$func = $addon . '_addon_admin';
 			$func($a, $admin_form);
 		}
diff --git a/mod/events.php b/mod/events.php
index cad440f164..bbd6337c37 100644
--- a/mod/events.php
+++ b/mod/events.php
@@ -433,6 +433,7 @@ function events_content(App $a) {
 		if (x($_REQUEST, 'location'))    {$orig_event['location']    = $_REQUEST['location'];}
 		if (x($_REQUEST, 'start'))       {$orig_event['start']       = $_REQUEST['start'];}
 		if (x($_REQUEST, 'finish'))      {$orig_event['finish']      = $_REQUEST['finish'];}
+		if (x($_REQUEST,'finish')) $orig_event['finish'] = $_REQUEST['finish'];
 
 		$n_checked = ((x($orig_event) && $orig_event['nofinish']) ? ' checked="checked" ' : '');
 		$a_checked = ((x($orig_event) && $orig_event['adjust'])   ? ' checked="checked" ' : '');
diff --git a/mod/photos.php b/mod/photos.php
index c8dad750d1..235acdfc47 100644
--- a/mod/photos.php
+++ b/mod/photos.php
@@ -1243,9 +1243,11 @@ function photos_content(App $a)
 		$prevlink = '';
 		$nextlink = '';
 
-		/// @todo This query is totally bad, the whole functionality has to be changed
-		// The query leads to a really intense used index.
-		// By now we hide it if someone wants to.
+		/*
+		 * @todo This query is totally bad, the whole functionality has to be changed
+		 * The query leads to a really intense used index.
+		 * By now we hide it if someone wants to.
+		 */
 		if (!Config::get('system', 'no_count', false)) {
 			$order_field = defaults($_GET, 'order', '');
 			if ($order_field === 'posted') {
@@ -1280,8 +1282,10 @@ function photos_content(App $a)
  			}
 		}
 
-		if (count($ph) == 1)
+		if (count($ph) == 1) {
 			$hires = $lores = $ph[0];
+		}
+
 		if (count($ph) > 1) {
 			if ($ph[1]['scale'] == 2) {
 				// original is 640 or less, we can display it directly
@@ -1293,6 +1297,7 @@ function photos_content(App $a)
 		}
 
 		$album_link = 'photos/' . $a->data['user']['nickname'] . '/album/' . bin2hex($ph[0]['album']);
+
 		$tools = null;
 		$lock = null;
 
@@ -1319,8 +1324,9 @@ function photos_content(App $a)
 			]);
 		}
 
-		if ($prevlink)
+		if ($prevlink) {
 			$prevlink = [$prevlink, '<div class="icon prev"></div>'] ;
+		}
 
 		$photo = [
 			'href' => 'photo/' . $hires['resource-id'] . '-' . $hires['scale'] . '.' . $phototypes[$hires['type']],
@@ -1681,8 +1687,9 @@ function photos_content(App $a)
 		$twist = false;
 		foreach ($r as $rr) {
 			//hide profile photos to others
-			if (!$is_owner && !remote_user() && ($rr['album'] == L10n::t('Profile Photos')))
+			if (!$is_owner && !remote_user() && ($rr['album'] == L10n::t('Profile Photos'))) {
 				continue;
+			}
 
 			$twist = !$twist;
 
diff --git a/mod/subthread.php b/mod/subthread.php
index c858f2d1fa..df44df6efa 100644
--- a/mod/subthread.php
+++ b/mod/subthread.php
@@ -63,17 +63,19 @@ function subthread_content(App $a) {
 		WHERE `contact`.`self` = 1 AND `contact`.`uid` = %d LIMIT 1",
 		intval($owner_uid)
 	);
-	if (DBM::is_result($r))
+
+	if (DBM::is_result($r)) {
 		$owner = $r[0];
+	}
 
 	if (! $owner) {
 		logger('like: no owner');
 		return;
 	}
 
-	if (! $remote_owner)
+	if (! $remote_owner) {
 		$remote_owner = $owner;
-
+	}
 
 	$contact = null;
 	// This represents the person posting
@@ -85,8 +87,10 @@ function subthread_content(App $a) {
 			intval($_SESSION['visitor_id']),
 			intval($owner_uid)
 		);
-		if (DBM::is_result($r))
+
+		if (DBM::is_result($r)) {
 			$contact = $r[0];
+		}
 	}
 	if (! $contact) {
 		return;
diff --git a/mod/tagger.php b/mod/tagger.php
index 16195cc339..211e2ffa1f 100644
--- a/mod/tagger.php
+++ b/mod/tagger.php
@@ -159,11 +159,13 @@ EOT;
 	}
 
 	$term_objtype = ($item['resource-id'] ? TERM_OBJ_PHOTO : TERM_OBJ_POST);
-        $t = q("SELECT count(tid) as tcount FROM term WHERE oid=%d AND term='%s'",
-                intval($item['id']),
-                dbesc($term)
-        );
-	if((! $blocktags) && $t[0]['tcount']==0 ) {
+
+	$t = q("SELECT count(tid) as tcount FROM term WHERE oid=%d AND term='%s'",
+		intval($item['id']),
+		dbesc($term)
+	);
+
+	if ((!$blocktags) && $t[0]['tcount'] == 0 ) {
 		q("INSERT INTO term (oid, otype, type, term, url, uid) VALUE (%d, %d, %d, '%s', '%s', %d)",
 		   intval($item['id']),
 		   $term_objtype,
@@ -176,26 +178,28 @@ EOT;
 
 	// if the original post is on this site, update it.
 
-	$r = q("select `tag`,`id`,`uid` from item where `origin` = 1 AND `uri` = '%s' LIMIT 1",
+	$r = q("SELECT `tag`,`id`,`uid` FROM `item` WHERE `origin`=1 AND `uri`='%s' LIMIT 1",
 		dbesc($item['uri'])
 	);
+
 	if (DBM::is_result($r)) {
-		$x = q("SELECT `blocktags` FROM `user` WHERE `uid` = %d limit 1",
+		$x = q("SELECT `blocktags` FROM `user` WHERE `uid`=%d LIMIT 1",
 			intval($r[0]['uid'])
 		);
-		$t = q("SELECT count(tid) as tcount FROM term WHERE oid=%d AND term='%s'",
+		$t = q("SELECT COUNT(`tid`) AS `tcount` FROM `term` WHERE `oid`=%d AND `term`='%s'",
 			intval($r[0]['id']),
 			dbesc($term)
 		);
-		if(count($x) && !$x[0]['blocktags'] && $t[0]['tcount']==0){
-			q("INSERT INTO term (oid, otype, type, term, url, uid) VALUE (%d, %d, %d, '%s', '%s', %d)",
-	                   intval($r[0]['id']),
-	                   $term_objtype,
-	                   TERM_HASHTAG,
-	                   dbesc($term),
-	                   dbesc(System::baseUrl() . '/search?tag=' . $term),
-	                   intval($owner_uid)
-	                );
+
+		if (DBM::is_result($x) && !$x[0]['blocktags'] && $t[0]['tcount'] == 0){
+			q("INSERT INTO term (`oid`, `otype`, `type`, `term`, `url`, `uid`) VALUE (%d, %d, %d, '%s', '%s', %d)",
+				intval($r[0]['id']),
+				$term_objtype,
+				TERM_HASHTAG,
+				dbesc($term),
+				dbesc(System::baseUrl() . '/search?tag=' . $term),
+				intval($owner_uid)
+			);
 		}
 	}
 
diff --git a/src/Core/Cache.php b/src/Core/Cache.php
index f1d1e11a54..4202db325c 100644
--- a/src/Core/Cache.php
+++ b/src/Core/Cache.php
@@ -40,6 +40,12 @@ class Cache extends \Friendica\BaseObject
 
 				self::$driver = new Cache\MemcachedCacheDriver($memcached_hosts);
 				break;
+			case 'redis':
+				$redis_host = Config::get('system', 'redis_host', '127.0.0.1');
+				$redis_port = Config::get('system', 'redis_port', 6379);
+
+				self::$driver = new Cache\RedisCacheDriver($redis_host, $redis_port);
+				break;
 			default:
 				self::$driver = new Cache\DatabaseCacheDriver();
 		}
diff --git a/src/Core/Cache/RedisCacheDriver.php b/src/Core/Cache/RedisCacheDriver.php
new file mode 100644
index 0000000000..fa98842da0
--- /dev/null
+++ b/src/Core/Cache/RedisCacheDriver.php
@@ -0,0 +1,77 @@
+<?php
+
+namespace Friendica\Core\Cache;
+
+use Friendica\BaseObject;
+use Friendica\Core\Cache;
+
+/**
+ * Redis Cache Driver. This driver is based on Memcache driver
+ *
+ * @author Hypolite Petovan <mrpetovan@gmail.com>
+ * @author Roland Haeder <roland@mxchange.org>
+ */
+class RedisCacheDriver extends BaseObject implements ICacheDriver
+{
+	/**
+	 * @var Redis
+	 */
+	private $redis;
+
+	public function __construct($redis_host, $redis_port)
+	{
+		if (!class_exists('Redis', false)) {
+			throw new \Exception('Redis class isn\'t available');
+		}
+
+		$this->redis = new \Redis();
+
+		if (!$this->redis->connect($redis_host, $redis_port)) {
+			throw new \Exception('Expected Redis server at ' . $redis_host . ':' . $redis_port . ' isn\'t available');
+		}
+	}
+
+	public function get($key)
+	{
+		$return = null;
+
+		// We fetch with the hostname as key to avoid problems with other applications
+		$cached = $this->redis->get(self::getApp()->get_hostname() . ':' . $key);
+
+		// @see http://php.net/manual/en/redis.get.php#84275
+		if (is_bool($cached) || is_double($cached) || is_long($cached)) {
+			return $return;
+		}
+
+		$value = @unserialize($cached);
+
+		// Only return a value if the serialized value is valid.
+		// We also check if the db entry is a serialized
+		// boolean 'false' value (which we want to return).
+		if ($cached === serialize(false) || $value !== false) {
+			$return = $value;
+		}
+
+		return $return;
+	}
+
+	public function set($key, $value, $duration = Cache::MONTH)
+	{
+		// We store with the hostname as key to avoid problems with other applications
+		return $this->redis->set(
+			self::getApp()->get_hostname() . ":" . $key,
+			serialize($value),
+			time() + $duration
+		);
+	}
+
+	public function delete($key)
+	{
+		return $this->redis->delete($key);
+	}
+
+	public function clear()
+	{
+		return true;
+	}
+}
diff --git a/src/Core/PConfig.php b/src/Core/PConfig.php
index bfa52f5a36..274122deda 100644
--- a/src/Core/PConfig.php
+++ b/src/Core/PConfig.php
@@ -29,9 +29,7 @@ class PConfig extends BaseObject
 
 	public static function init($uid)
 	{
-		$a = self::getApp();
-
-		if (isset($a->config['system']['config_adapter']) && $a->config['system']['config_adapter'] == 'preload') {
+		if (Config::get('system', 'config_adapter') == 'preload') {
 			self::$adapter = new Config\PreloadPConfigAdapter($uid);
 		} else {
 			self::$adapter = new Config\JITPConfigAdapter($uid);
diff --git a/src/Core/Worker.php b/src/Core/Worker.php
index e3d8df45e4..8c8e273318 100644
--- a/src/Core/Worker.php
+++ b/src/Core/Worker.php
@@ -688,7 +688,7 @@ class Worker
 			logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries.$processlist." - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 
 			// Are there fewer workers running as possible? Then fork a new one.
-			if (!Config::get("system", "worker_dont_fork") && ($queues > ($active + 1)) && ($entries > 1)) {
+			if (!Config::get("system", "worker_dont_fork", false) && ($queues > ($active + 1)) && ($entries > 1)) {
 				logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 				self::spawnWorker();
 			}
@@ -1039,7 +1039,7 @@ class Worker
 		}
 
 		$priority = PRIORITY_MEDIUM;
-		$dont_fork = Config::get("system", "worker_dont_fork");
+		$dont_fork = Config::get("system", "worker_dont_fork", false);
 		$created = DateTimeFormat::utcNow();
 
 		$run_parameter = array_shift($args);
diff --git a/src/Model/Event.php b/src/Model/Event.php
index e65e61ee58..db9e2b9303 100644
--- a/src/Model/Event.php
+++ b/src/Model/Event.php
@@ -803,10 +803,10 @@ class Event extends BaseObject
 	/**
 	 * @brief Format an item array with event data to HTML.
 	 *
-	 * @param arr $item Array with item and event data.
+	 * @param array $item Array with item and event data.
 	 * @return string HTML output.
 	 */
-	public static function getItemHTML($item) {
+	public static function getItemHTML(array $item) {
 		$same_date = false;
 		$finish    = false;
 
diff --git a/src/Model/Item.php b/src/Model/Item.php
index 425f71822a..bf1193d709 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -1032,8 +1032,9 @@ class Item extends BaseObject
 		}
 
 		// Is this a shadow entry?
-		if ($item['uid'] == 0)
+		if ($item['uid'] == 0) {
 			return;
+		}
 
 		// Is there a shadow parent?
 		if (!dba::exists('item', ['uri' => $item['parent-uri'], 'uid' => 0])) {
@@ -1073,10 +1074,8 @@ class Item extends BaseObject
 
 		// If this was a comment to a Diaspora post we don't get our comment back.
 		// This means that we have to distribute the comment by ourselves.
-		if ($origin) {
-			if (dba::exists('item', ['id' => $parent, 'network' => NETWORK_DIASPORA])) {
-				self::distribute($public_shadow);
-			}
+		if ($origin && dba::exists('item', ['id' => $parent, 'network' => NETWORK_DIASPORA])) {
+			self::distribute($public_shadow);
 		}
 	}
 
@@ -1087,14 +1086,14 @@ class Item extends BaseObject
 	 */
 	private static function addLanguageInPostopts(&$item)
 	{
+		$postopts = "";
+
 		if (!empty($item['postopts'])) {
 			if (strstr($item['postopts'], 'lang=')) {
 				// do not override
 				return;
 			}
 			$postopts = $item['postopts'];
-		} else {
-			$postopts = "";
 		}
 
 		$naked_body = Text\BBCode::toPlaintext($item['body'], false);
diff --git a/src/Protocol/DFRN.php b/src/Protocol/DFRN.php
index 00bb91f8de..d738adecb8 100644
--- a/src/Protocol/DFRN.php
+++ b/src/Protocol/DFRN.php
@@ -81,7 +81,7 @@ class DFRN
 			$root->appendChild($entry);
 		}
 
-		return(trim($doc->saveXML()));
+		return trim($doc->saveXML());
 	}
 
 	/**
@@ -96,7 +96,6 @@ class DFRN
 	 * @param boolean $onlyheader  Output only the header without content? (Default is "no")
 	 *
 	 * @return string DFRN feed entries
-	 * @todo Find proper type-hints
 	 */
 	public static function feed($dfrn_id, $owner_nick, $last_update, $direction = 0, $onlyheader = false)
 	{
@@ -222,10 +221,8 @@ class DFRN
 			//$sql_extra .= file_tag_file_query('item',$category,'category');
 		}
 
-		if ($public_feed) {
-			if (! $converse) {
-				$sql_extra .= " AND `contact`.`self` = 1 ";
-			}
+		if ($public_feed && ! $converse) {
+			$sql_extra .= " AND `contact`.`self` = 1 ";
 		}
 
 		$check_date = DateTimeFormat::utc($last_update);
@@ -426,7 +423,7 @@ class DFRN
 
 		$root->appendChild($mail);
 
-		return(trim($doc->saveXML()));
+		return trim($doc->saveXML());
 	}
 
 	/**
@@ -455,7 +452,7 @@ class DFRN
 
 		$root->appendChild($suggest);
 
-		return(trim($doc->saveXML()));
+		return trim($doc->saveXML());
 	}
 
 	/**
@@ -490,7 +487,6 @@ class DFRN
 			$photos[$p['scale']] = System::baseUrl().'/photo/'.$p['resource-id'].'-'.$p['scale'].'.'.$ext[$p['type']];
 		}
 
-		unset($rp, $ext);
 
 		$doc = new DOMDocument('1.0', 'utf-8');
 		$doc->formatOutput = true;
@@ -514,7 +510,7 @@ class DFRN
 
 		$root->appendChild($relocate);
 
-		return(trim($doc->saveXML()));
+		return trim($doc->saveXML());
 	}
 
 	/**
@@ -896,7 +892,7 @@ class DFRN
 	 * @return object XML entry object
 	 * @todo Find proper type-hints
 	 */
-	private static function entry($doc, $type, $item, $owner, $comment = false, $cid = 0, $single = false)
+	private static function entry($doc, $type, array $item, array $owner, $comment = false, $cid = 0, $single = false)
 	{
 		$mentioned = [];
 
@@ -940,7 +936,7 @@ class DFRN
 			$htmlbody = $body;
 
 			if ($item['title'] != "") {
-				$htmlbody = "[b]".$item['title']."[/b]\n\n".$htmlbody;
+				$htmlbody = "[b]" . $item['title'] . "[/b]\n\n" . $htmlbody;
 			}
 
 			$htmlbody = BBCode::convert($htmlbody, false, 7);
@@ -1067,6 +1063,7 @@ class DFRN
 
 		$tags = Item::getFeedTags($item);
 
+		/// @TODO Combine this with similar below if() block?
 		if (count($tags)) {
 			foreach ($tags as $t) {
 				if (($type != 'html') || ($t[0] != "@")) {
@@ -1576,7 +1573,7 @@ class DFRN
 		// Until now we aren't serving different sizes - but maybe later
 		$avatarlist = [];
 		/// @todo check if "avatar" or "photo" would be the best field in the specification
-		$avatars = $xpath->query($element."/atom:link[@rel='avatar']", $context);
+		$avatars = $xpath->query($element . "/atom:link[@rel='avatar']", $context);
 		foreach ($avatars as $avatar) {
 			$href = "";
 			$width = 0;
@@ -1596,6 +1593,7 @@ class DFRN
 				$avatarlist[$width] = $href;
 			}
 		}
+
 		if (count($avatarlist) > 0) {
 			krsort($avatarlist);
 			$author["avatar"] = current($avatarlist);
@@ -2098,6 +2096,9 @@ class DFRN
 		$condition = ["(`id` = ?) OR (`nurl` = ?)", $importer["id"], normalise_link($old["url"])];
 		dba::update('contact', $fields, $condition);
 
+		// @TODO No dba:update here?
+		dba::update('contact', $fields, $condition);
+
 		Contact::updateAvatar($relocate["avatar"], $importer["importer_uid"], $importer["id"], true);
 
 		logger('Contacts are updated.');
@@ -2708,7 +2709,7 @@ class DFRN
 			if (self::updateContent($current, $item, $importer, $entrytype)) {
 				logger("Item ".$item["uri"]." was updated.", LOGGER_DEBUG);
 			} else {
-				logger("Item ".$item["uri"]." already existed.", LOGGER_DEBUG);
+				logger("Item " . $item["uri"] . " already existed.", LOGGER_DEBUG);
 			}
 			return;
 		}
diff --git a/src/Protocol/OStatus.php b/src/Protocol/OStatus.php
index 8b69392144..8dac2b456c 100644
--- a/src/Protocol/OStatus.php
+++ b/src/Protocol/OStatus.php
@@ -1948,7 +1948,7 @@ class OStatus
 	 * @param bool   $complete default true
 	 * @return void
 	 */
-	private static function entryFooter($doc, $entry, $item, $owner, $complete = true)
+	private static function entryFooter($doc, $entry, array $item, array $owner, $complete = true)
 	{
 		$mentioned = [];
 
@@ -1988,6 +1988,7 @@ class OStatus
 
 			if (isset($parent_item)) {
 				$r = dba::fetch_first("SELECT `conversation-uri`, `conversation-href` FROM `conversation` WHERE `item-uri` = ?", $parent_item);
+
 				if (DBM::is_result($r)) {
 					if ($r['conversation-uri'] != '') {
 						$conversation_uri = $r['conversation-uri'];
@@ -2048,9 +2049,11 @@ class OStatus
 		}
 
 		if ($owner['account-type'] == ACCOUNT_TYPE_COMMUNITY) {
-			XML::addElement($doc, $entry, "link", "", ["rel" => "mentioned",
-									"ostatus:object-type" => "http://activitystrea.ms/schema/1.0/group",
-									"href" => $owner['url']]);
+			XML::addElement($doc, $entry, "link", "", [
+				"rel" => "mentioned",
+				"ostatus:object-type" => "http://activitystrea.ms/schema/1.0/group",
+				"href" => $owner['url']
+			]);
 		}
 
 		if (!$item["private"]) {
diff --git a/src/Protocol/PortableContact.php b/src/Protocol/PortableContact.php
index 672956ffb9..50b903fb02 100644
--- a/src/Protocol/PortableContact.php
+++ b/src/Protocol/PortableContact.php
@@ -1316,20 +1316,8 @@ class PortableContact
 					$version = $data->version;
 					$site_name = $data->site_name;
 					$info = $data->info;
-					$register_policy_str = $data->register_policy;
+					$register_policy = constant($data->register_policy);
 					$platform = $data->platform;
-
-					switch ($register_policy_str) {
-						case "REGISTER_CLOSED":
-							$register_policy = REGISTER_CLOSED;
-							break;
-						case "REGISTER_APPROVE":
-							$register_policy = REGISTER_APPROVE;
-							break;
-						case "REGISTER_OPEN":
-							$register_policy = REGISTER_OPEN;
-							break;
-					}
 				}
 			}
 		}