diff --git a/dependabot.yml b/.github/dependabot.yml
similarity index 100%
rename from dependabot.yml
rename to .github/dependabot.yml
diff --git a/.github/workflows/quality-assurance-php.yml b/.github/workflows/quality-assurance-php.yml
index cee505f..d5dfc5e 100644
--- a/.github/workflows/quality-assurance-php.yml
+++ b/.github/workflows/quality-assurance-php.yml
@@ -8,6 +8,7 @@ on:
             - '**phpcs.xml.dist'
             - '**phpunit.xml.dist'
             - '**psalm.xml'
+            - '**ruleset.xml'
     workflow_dispatch:
         inputs:
             jobs:
diff --git a/.psalm/autoloader.php b/.psalm/autoloader.php
deleted file mode 100644
index 86ace84..0000000
--- a/.psalm/autoloader.php
+++ /dev/null
@@ -1,14 +0,0 @@
-<?php
-
-$vendor = dirname(__DIR__) . '/vendor';
-$phpcsSrc = "{$vendor}/squizlabs/php_codesniffer/src";
-
-require_once dirname(__DIR__) . '/Inpsyde/PhpcsHelpers.php';
-require_once "{$phpcsSrc}/Sniffs/Sniff.php";
-require_once "{$phpcsSrc}/Files/File.php";
-require_once "{$phpcsSrc}/Fixer.php";
-require_once "{$phpcsSrc}/Util/Tokens.php";
-require_once "{$phpcsSrc}/Standards/Generic/Sniffs/PHP/DisallowShortOpenTagSniff.php";
-require_once "{$phpcsSrc}/Standards/PSR12/Sniffs/Properties/ConstantVisibilitySniff.php";
-require_once "{$phpcsSrc}/Config.php";
-require_once "{$phpcsSrc}/Exceptions/RuntimeException.php";
diff --git a/Inpsyde/PhpcsHelpers.php b/Inpsyde/PhpcsHelpers.php
index 64dde5a..39b887c 100644
--- a/Inpsyde/PhpcsHelpers.php
+++ b/Inpsyde/PhpcsHelpers.php
@@ -590,8 +590,7 @@ public static function isVoidReturn(
      */
     public static function isNullReturn(File $file, int $returnPosition): bool
     {
-        return
-            !self::isVoidReturn($file, $returnPosition, false)
+        return !self::isVoidReturn($file, $returnPosition, false)
             && self::isVoidReturn($file, $returnPosition, true);
     }
 
diff --git a/Inpsyde/Sniffs/CodeQuality/DisableCallUserFuncSniff.php b/Inpsyde/Sniffs/CodeQuality/DisableCallUserFuncSniff.php
new file mode 100644
index 0000000..9f6428c
--- /dev/null
+++ b/Inpsyde/Sniffs/CodeQuality/DisableCallUserFuncSniff.php
@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * This file is part of the "php-coding-standards" package.
+ *
+ * Copyright (C) 2023 Inpsyde GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+declare(strict_types=1);
+
+namespace Inpsyde\Sniffs\CodeQuality;
+
+use WordPressCS\WordPress\AbstractFunctionRestrictionsSniff;
+
+class DisableCallUserFuncSniff extends AbstractFunctionRestrictionsSniff
+{
+    /**
+     * @return array<string, array<string, string|array>>
+     *
+     * phpcs:disable Inpsyde.CodeQuality.NoAccessors
+     */
+    public function getGroups(): array
+    {
+        // phpcs:enable Inpsyde.CodeQuality.NoAccessors
+        return [
+            'call_user_func' => [
+                'type' => 'error',
+                'message' => 'Usage of %s() is forbidden.',
+                'functions' => [
+                    'call_user_func',
+                    'call_user_func_array',
+                ],
+            ],
+        ];
+    }
+}
diff --git a/Inpsyde/Sniffs/CodeQuality/DisableMagicSerializeSniff.php b/Inpsyde/Sniffs/CodeQuality/DisableMagicSerializeSniff.php
new file mode 100644
index 0000000..2d8180a
--- /dev/null
+++ b/Inpsyde/Sniffs/CodeQuality/DisableMagicSerializeSniff.php
@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * This file is part of the "php-coding-standards" package.
+ *
+ * Copyright (C) 2023 Inpsyde GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+declare(strict_types=1);
+
+namespace Inpsyde\Sniffs\CodeQuality;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Sniffs\Sniff;
+use PHPCSUtils\Utils\FunctionDeclarations;
+use PHPCSUtils\Utils\Scopes;
+
+class DisableMagicSerializeSniff implements Sniff
+{
+    /** @var list<string>  */
+    public array $disabledFunctions = [
+        '__serialize',
+        '__sleep',
+        '__unserialize',
+        '__wakeup',
+    ];
+
+    /**
+     * @return list<int>
+     */
+    public function register(): array
+    {
+        return [T_FUNCTION];
+    }
+
+    /**
+     * @param File $phpcsFile
+     * @param int $stackPtr
+     * @return void
+     *
+     * phpcs:disable Inpsyde.CodeQuality.ArgumentTypeDeclaration
+     */
+    public function process(File $phpcsFile, $stackPtr)
+    {
+        // phpcs:enable Inpsyde.CodeQuality.ArgumentTypeDeclaration
+        if (!Scopes::isOOMethod($phpcsFile, $stackPtr)) {
+            return;
+        }
+
+        $name = FunctionDeclarations::getName($phpcsFile, $stackPtr);
+        if (in_array($name, $this->disabledFunctions, true)) {
+            $phpcsFile->addError(
+                sprintf(
+                    'The method "%s" is forbidden, please use Serializable interface.',
+                    $name
+                ),
+                $stackPtr,
+                'Found'
+            );
+        }
+    }
+}
diff --git a/Inpsyde/Sniffs/CodeQuality/NoRootNamespaceFunctionsSniff.php b/Inpsyde/Sniffs/CodeQuality/NoRootNamespaceFunctionsSniff.php
new file mode 100644
index 0000000..3c8ad58
--- /dev/null
+++ b/Inpsyde/Sniffs/CodeQuality/NoRootNamespaceFunctionsSniff.php
@@ -0,0 +1,71 @@
+<?php
+
+/**
+ * This file is part of the "php-coding-standards" package.
+ *
+ * Copyright (C) 2023 Inpsyde GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+declare(strict_types=1);
+
+namespace Inpsyde\Sniffs\CodeQuality;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Sniffs\Sniff;
+use PHPCSUtils\Utils\FunctionDeclarations;
+use PHPCSUtils\Utils\Namespaces;
+use PHPCSUtils\Utils\ObjectDeclarations;
+use PHPCSUtils\Utils\Scopes;
+
+class NoRootNamespaceFunctionsSniff implements Sniff
+{
+    /**
+     * @return list<int>
+     */
+    public function register(): array
+    {
+        return [T_FUNCTION];
+    }
+
+    /**
+     * @param File $phpcsFile
+     * @param int $stackPtr
+     * @return void
+     *
+     * phpcs:disable Inpsyde.CodeQuality.ArgumentTypeDeclaration
+     */
+    public function process(File $phpcsFile, $stackPtr): void
+    {
+        // phpcs:enable Inpsyde.CodeQuality.ArgumentTypeDeclaration
+        if (Scopes::isOOMethod($phpcsFile, $stackPtr)) {
+            return;
+        }
+
+        $namespace = Namespaces::determineNamespace($phpcsFile, $stackPtr);
+        if ($namespace !== '') {
+            return;
+        }
+        $name = FunctionDeclarations::getName($phpcsFile, $stackPtr);
+        if (!$name) {
+            return;
+        }
+
+        $message = sprintf('The function "%s" is in root namespace.', $name);
+
+        $phpcsFile->addError($message, $stackPtr, 'Found');
+    }
+}
diff --git a/Inpsyde/ruleset.xml b/Inpsyde/ruleset.xml
index c70db7a..d51b281 100644
--- a/Inpsyde/ruleset.xml
+++ b/Inpsyde/ruleset.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
-<ruleset name="Inpsyde Coding Standard">
+<ruleset name="Inpsyde PHP Coding Standard">
 
     <description>PHP 7+ coding standards for Inpsyde WordPress projects.</description>
 
@@ -13,45 +13,22 @@
         <exclude name="Generic.Files.LineLength.TooLong"/>
     </rule>
 
-    <!--
-    Neutron standard are quality tools for PHP7 development from Automattic.
-    See https://github.com/Automattic/phpcs-neutron-standard
-    -->
-    <rule ref="NeutronStandard.AssignAlign.DisallowAssignAlign">
-        <type>warning</type>
-    </rule>
-    <rule ref="NeutronStandard.Functions.DisallowCallUserFunc">
-        <type>warning</type>
-    </rule>
-    <rule ref="NeutronStandard.Globals.DisallowGlobalFunctions">
-        <type>warning</type>
-    </rule>
-    <rule ref="NeutronStandard.MagicMethods.DisallowMagicSerialize">
-        <type>warning</type>
-    </rule>
-    <rule ref="NeutronStandard.StrictTypes.RequireStrictTypes">
-        <type>warning</type>
-    </rule>
-    <rule ref="NeutronStandard.Whitespace.DisallowMultipleNewlines">
-        <type>warning</type>
-    </rule>
-    <rule ref="NeutronStandard.Whitespace.RequireNewlineBetweenFunctions">
-        <type>warning</type>
-    </rule>
-
     <!--
     Curated list of WordPress specific rules.
     See https://github.com/WordPress-Coding-Standards/WordPress-Coding-Standards
     -->
-    <rule ref="WordPress.Arrays.CommaAfterArrayItem"/>
-    <rule ref="WordPress.CodeAnalysis.AssignmentInCondition"/>
-    <rule ref="WordPress.CodeAnalysis.EmptyStatement"/>
+    <rule ref="WordPress.CodeAnalysis.AssignmentInTernaryCondition"/>
     <rule ref="WordPress.CodeAnalysis.EscapedNotTranslated"/>
     <rule ref="WordPress.DB.PreparedSQLPlaceholders"/>
     <rule ref="WordPress.DB.PreparedSQL"/>
     <rule ref="WordPress.DB.RestrictedClasses"/>
     <rule ref="WordPress.DB.RestrictedFunctions"/>
     <rule ref="WordPress.DateTime.CurrentTimeTimestamp"/>
+    <rule ref="WordPress.DateTime.RestrictedFunctions">
+        <properties>
+            <property name="exclude" type="array" value="date"/>
+        </properties>
+    </rule>
     <rule ref="WordPress.NamingConventions.PrefixAllGlobals"/>
     <rule ref="WordPress.NamingConventions.ValidHookName">
         <properties>
@@ -81,7 +58,6 @@
     <rule ref="WordPress.PHP.POSIXFunctions"/>
     <rule ref="WordPress.PHP.PregQuoteDelimiter"/>
     <rule ref="WordPress.PHP.RestrictedPHPFunctions"/>
-    <rule ref="WordPress.PHP.StrictComparisons"/>
     <rule ref="WordPress.PHP.StrictInArray"/>
     <rule ref="WordPress.PHP.TypeCasts"/>
     <rule ref="WordPress.Security.EscapeOutput"/>
@@ -131,10 +107,38 @@
         <exclude name="VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable" />
     </rule>
 
+    <!--
+    PHPCS Extra
+    -->
+    <rule ref="NormalizedArrays.Arrays.CommaAfterLast" />
+    <rule ref="Universal.Operators.StrictComparisons" />
+    <rule ref="Universal.WhiteSpace.PrecisionAlignment" />
+
+    <!--
+    Slevomat
+    -->
+    <rule ref="SlevomatCodingStandard.Functions.ArrowFunctionDeclaration">
+        <properties>
+            <property name="allowMultiLine" type="boolean" value="yes"/>
+        </properties>
+    </rule>
+    <rule ref="SlevomatCodingStandard.TypeHints.DeclareStrictTypes">
+        <properties>
+            <property name="spacesCountAroundEqualsSign" type="integer" value="0"/>
+        </properties>
+    </rule>
+    <rule ref="SlevomatCodingStandard.Whitespaces.DuplicateSpaces">
+        <properties>
+            <property type="boolean" name="ignoreSpacesInComment" value="yes" />
+        </properties>
+    </rule>
+
     <!--
     Generic
     -->
     <rule ref="Generic.Arrays.DisallowLongArraySyntax"/>
+    <rule ref="Generic.CodeAnalysis.AssignmentInCondition"/>
+    <rule ref="Generic.CodeAnalysis.EmptyPHPStatement"/>
     <rule ref="Generic.Metrics.CyclomaticComplexity">
         <properties>
             <property name="absoluteComplexity" value="50"/>
@@ -144,6 +148,13 @@
     <rule ref="Generic.PHP.CharacterBeforePHPOpeningTag"/>
     <rule ref="Generic.PHP.LowerCaseConstant"/>
     <rule ref="Generic.VersionControl.GitMergeConflict"/>
+    <rule ref="Generic.WhiteSpace.ArbitraryParenthesesSpacing">
+        <properties>
+            <property type="boolean" name="ignoreNewlines" value="yes" />
+        </properties>
+    </rule>
+    <rule ref="Generic.WhiteSpace.LanguageConstructSpacing"/>
+    <rule ref="Generic.WhiteSpace.SpreadOperatorSpacingAfter"/>
     <rule ref="Squiz.Classes.LowercaseClassKeywords"/>
     <rule ref="Squiz.PHP.CommentedOutCode">
         <properties>
@@ -156,6 +167,13 @@
     <rule ref="Squiz.PHP.NonExecutableCode"/>
     <rule ref="Squiz.Scope.MemberVarScope"/>
     <rule ref="Squiz.Scope.StaticThisUsage"/>
+    <rule ref="Squiz.WhiteSpace.FunctionSpacing">
+        <properties>
+            <property name="spacing" value="1"/>
+            <property name="spacingBeforeFirst" value="0"/>
+            <property name="spacingAfterLast" value="0"/>
+        </properties>
+    </rule>
 
     <!--
     PHPCompatibility
diff --git a/composer.json b/composer.json
index ea4c1a9..0b63cc2 100644
--- a/composer.json
+++ b/composer.json
@@ -30,10 +30,12 @@
     "minimum-stability": "stable",
     "require": {
         "php": ">=7.4",
-        "dealerdirect/phpcodesniffer-composer-installer": "~1.0.0",
         "automattic/vipwpcs": "dev-develop",
+        "dealerdirect/phpcodesniffer-composer-installer": "~1.0.0",
         "phpcompatibility/php-compatibility": "^9.3.5",
-        "automattic/phpcs-neutron-standard": "^v1.7.0"
+        "phpcsstandards/phpcsextra": "^1.1",
+        "phpcsstandards/phpcsutils": "^1.0",
+        "slevomat/coding-standard": "^8.13"
     },
     "require-dev": {
         "phpunit/phpunit": "^9.6.11",
@@ -65,6 +67,7 @@
         ]
     },
     "config": {
+        "sort-packages": true,
         "allow-plugins": {
             "inpsyde/*": true,
             "composer/*": true,
diff --git a/phpcs.xml b/phpcs.xml
index f8ebb51..0cfa7e3 100644
--- a/phpcs.xml
+++ b/phpcs.xml
@@ -3,8 +3,6 @@
 
     <description>PHP 7+ coding standards for Inpsyde WordPress projects.</description>
 
-    <autoload>./Inpsyde/PhpcsHelpers.php</autoload>
-
     <file>./Inpsyde/Sniffs</file>
     <file>./Inpsyde/PhpcsHelpers.php</file>
     <file>./tests/src</file>
@@ -21,118 +19,8 @@
     <arg name="colors"/>
     <arg value="sp"/>
 
-    <!--
-    PSR 12 Code style.
-    See http://www.php-fig.org/psr/psr-12/
-    -->
-    <rule ref="PSR12">
-        <exclude name="Generic.Files.LineLength.TooLong"/>
+    <rule ref="Inpsyde">
+        <exclude name="WordPress.Security"/>
     </rule>
 
-    <!--
-    Curated list of WordPress specific rules.
-    See https://github.com/WordPress-Coding-Standards/WordPress-Coding-Standards
-    -->
-    <rule ref="WordPress.CodeAnalysis.AssignmentInTernaryCondition"/>
-    <rule ref="WordPress.CodeAnalysis.EscapedNotTranslated"/>
-    <rule ref="WordPress.DB.PreparedSQLPlaceholders"/>
-    <rule ref="WordPress.DB.PreparedSQL"/>
-    <rule ref="WordPress.DB.RestrictedClasses"/>
-    <rule ref="WordPress.DB.RestrictedFunctions"/>
-    <rule ref="WordPress.PHP.DontExtract"/>
-    <rule ref="WordPress.PHP.IniSet"/>
-    <rule ref="WordPress.PHP.NoSilencedErrors"/>
-    <rule ref="WordPress.PHP.POSIXFunctions"/>
-    <rule ref="WordPress.PHP.PregQuoteDelimiter"/>
-    <rule ref="WordPress.PHP.RestrictedPHPFunctions"/>
-    <rule ref="WordPress.PHP.StrictInArray"/>
-    <rule ref="WordPress.PHP.TypeCasts"/>
-    <rule ref="WordPress.Security.SafeRedirect"/>
-    <rule ref="WordPress.WP.CapitalPDangit"/>
-    <rule ref="WordPress.WP.DeprecatedClasses"/>
-    <rule ref="WordPress.WP.DeprecatedFunctions"/>
-    <rule ref="WordPress.WP.DeprecatedParameters"/>
-    <rule ref="WordPress.WP.DeprecatedParameterValues"/>
-    <rule ref="WordPress.WP.DiscouragedConstants"/>
-    <rule ref="WordPress.WP.DiscouragedFunctions"/>
-
-    <!--
-    Curated list of WordPress VIP rules.
-    See https://github.com/Automattic/VIP-Coding-Standards/
-    -->
-    <rule ref="WordPressVIPMinimum.Classes.DeclarationCompatibility"/>
-    <rule ref="WordPressVIPMinimum.Constants.ConstantString"/>
-    <rule ref="WordPressVIPMinimum.Constants.RestrictedConstants"/>
-    <rule ref="WordPressVIPMinimum.Files.IncludingNonPHPFile"/>
-    <rule ref="WordPressVIPMinimum.Functions.CheckReturnValue"/>
-    <rule ref="WordPressVIPMinimum.Functions.DynamicCalls"/>
-    <rule ref="WordPressVIPMinimum.Functions.StripTags"/>
-    <rule ref="WordPressVIPMinimum.Hooks.AlwaysReturnInFilter"/>
-    <rule ref="WordPressVIPMinimum.Hooks.PreGetPosts"/>
-    <rule ref="WordPressVIPMinimum.Performance.RegexpCompare"/>
-    <rule ref="WordPressVIPMinimum.Security.EscapingVoidReturnFunctions"/>
-    <rule ref="WordPressVIPMinimum.Security.ExitAfterRedirect"/>
-    <rule ref="WordPressVIPMinimum.Security.PHPFilterFunctions"/>
-    <rule ref="WordPressVIPMinimum.Security.ProperEscapingFunction"/>
-    <rule ref="WordPressVIPMinimum.Security.StaticStrreplace"/>
-    <rule ref="VariableAnalysis.CodeAnalysis.VariableAnalysis">
-        <exclude name="VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable" />
-    </rule>
-
-    <!--
-    Generic
-    -->
-    <rule ref="Generic.Arrays.DisallowLongArraySyntax"/>
-    <rule ref="Generic.CodeAnalysis.AssignmentInCondition"/>
-    <rule ref="Generic.CodeAnalysis.EmptyPHPStatement"/>
-    <rule ref="Generic.Metrics.CyclomaticComplexity">
-        <properties>
-            <property name="absoluteComplexity" value="50"/>
-        </properties>
-    </rule>
-    <rule ref="Generic.NamingConventions.ConstructorName"/>
-    <rule ref="Generic.PHP.CharacterBeforePHPOpeningTag"/>
-    <rule ref="Generic.PHP.LowerCaseConstant"/>
-    <rule ref="Generic.VersionControl.GitMergeConflict"/>
-    <rule ref="NormalizedArrays.Arrays.CommaAfterLast"/>
-    <rule ref="Squiz.Classes.LowercaseClassKeywords"/>
-    <rule ref="Squiz.PHP.CommentedOutCode">
-        <properties>
-            <property name="maxPercentage" value="45"/>
-        </properties>
-    </rule>
-    <rule ref="Squiz.PHP.Eval"/>
-    <rule ref="Squiz.PHP.InnerFunctions"/>
-    <rule ref="Squiz.PHP.LowercasePHPFunctions"/>
-    <rule ref="Squiz.PHP.NonExecutableCode"/>
-    <rule ref="Squiz.Scope.MemberVarScope"/>
-    <rule ref="Squiz.Scope.StaticThisUsage"/>
-    <rule ref="Universal.Operators.StrictComparisons" />
-    <rule ref="Universal.WhiteSpace.CommaSpacing"/>
-
-    <!--
-    PHPCompatibility
-    -->
-    <rule ref="PHPCompatibility"/>
-
-    <!--
-    Use own rules :)
-    -->
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/ArgumentTypeDeclarationSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/DisallowShortOpenTagSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/ElementNameMinimalLengthSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/ForbiddenPublicPropertySniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/FunctionBodyStartSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/FunctionLengthSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/LineLengthSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/NestingLevelSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/NoAccessorsSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/NoElseSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/NoTopLevelDefineSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/PropertyPerClassLimitSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/Psr4Sniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/ReturnTypeDeclarationSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/StaticClosureSniff.php"/>
-    <rule ref="./Inpsyde/Sniffs/CodeQuality/VariablesNameSniff.php"/>
-
 </ruleset>
diff --git a/psalm.xml b/psalm.xml
index 53e46c1..7399676 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <psalm
     errorLevel="1"
-    autoloader="./.psalm/autoloader.php"
+    autoloader="./tests/autoload.php"
     useDocblockPropertyTypes="true"
     usePhpDocMethodsWithoutMagicCall="true"
     strictBinaryOperands="true"
diff --git a/tests/autoload.php b/tests/autoload.php
new file mode 100644
index 0000000..3b6fc50
--- /dev/null
+++ b/tests/autoload.php
@@ -0,0 +1,17 @@
+<?php
+
+$vendorDir = dirname(__DIR__) . '/vendor';
+
+require_once "{$vendorDir}/squizlabs/php_codesniffer/autoload.php";
+
+require_once "{$vendorDir}/squizlabs/php_codesniffer/tests/bootstrap.php";
+require_once "{$vendorDir}/wp-coding-standards/wpcs/WordPress/Sniff.php";
+require_once "{$vendorDir}/wp-coding-standards/wpcs/WordPress/AbstractArrayAssignmentRestrictionsSniff.php";
+require_once "{$vendorDir}/wp-coding-standards/wpcs/WordPress/AbstractFunctionRestrictionsSniff.php";
+require_once "{$vendorDir}/wp-coding-standards/wpcs/WordPress/AbstractFunctionParameterSniff.php";
+require_once "{$vendorDir}/wp-coding-standards/wpcs/WordPress/AbstractClassRestrictionsSniff.php";
+foreach (glob("{$vendorDir}/wp-coding-standards/wpcs/WordPress/Helpers/*.php") as $file) {
+    require_once $file;
+}
+
+require_once dirname(__DIR__) . '/Inpsyde/PhpcsHelpers.php';
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 6fd220d..4af51ce 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -29,9 +29,7 @@
     require_once $autoload;
 }
 
-require_once "{$vendorDir}/squizlabs/php_codesniffer/autoload.php";
-require_once "{$vendorDir}/squizlabs/php_codesniffer/tests/bootstrap.php";
-require_once "{$libDir}/Inpsyde/PhpcsHelpers.php";
+require_once "{$testsDir}/autoload.php";
 
 unset($libDir, $testsDir, $vendorDir, $autoload);
 
diff --git a/tests/fixtures/disable-call-user-func.php b/tests/fixtures/disable-call-user-func.php
new file mode 100644
index 0000000..7f2374a
--- /dev/null
+++ b/tests/fixtures/disable-call-user-func.php
@@ -0,0 +1,22 @@
+<?php
+// @phpcsSniff CodeQuality.DisableCallUserFunc
+
+function test() {
+    // @phpcsErrorOnNextLine
+    return call_user_func('strtolower', 'foo');
+}
+
+echo 'call_user_func_array';
+
+$foo = [
+    'call_user_func',
+    'call_user_func_array',
+];
+
+class Foo {
+
+    private function test() {
+        // @phpcsErrorOnNextLine
+        return call_user_func_array('strtolower', ['foo']);
+    }
+}
diff --git a/tests/fixtures/disallow-magic-serialize.php b/tests/fixtures/disallow-magic-serialize.php
new file mode 100644
index 0000000..cf7f2ea
--- /dev/null
+++ b/tests/fixtures/disallow-magic-serialize.php
@@ -0,0 +1,50 @@
+<?php
+
+// @phpcsSniff CodeQuality.DisableMagicSerialize
+
+class Foo {
+
+    // @phpcsErrorOnNextLine
+    public function __serialize(): array
+    {
+        return [];
+    }
+
+    public function serialize(): array
+    {
+        return [];
+    }
+
+    // @phpcsErrorOnNextLine
+    public function __sleep(): array
+    {
+        return [];
+    }
+
+    public function sleep(): array
+    {
+        return [];
+    }
+
+    // @phpcsErrorOnNextLine
+    public function __wakeup(): array
+    {
+        return [];
+    }
+
+    public function wakeup(): array
+    {
+        return [];
+    }
+
+    // @phpcsErrorOnNextLine
+    public function __unserialize(): array
+    {
+        return [];
+    }
+
+    public function unserialize(): array
+    {
+        return [];
+    }
+}
diff --git a/tests/fixtures/no-root-namespace-functions-multi.php b/tests/fixtures/no-root-namespace-functions-multi.php
new file mode 100644
index 0000000..caa3f38
--- /dev/null
+++ b/tests/fixtures/no-root-namespace-functions-multi.php
@@ -0,0 +1,31 @@
+<?php
+// @phpcsSniff CodeQuality.NoRootNamespaceFunctions
+
+namespace Foo {
+
+    function test() {
+
+    }
+}
+
+namespace Foo\Bar {
+
+    function test() {
+
+    }
+}
+
+namespace {
+
+    class Foo
+    {
+        function test() {
+
+        }
+    }
+
+    // @phpcsErrorOnNextLine
+    function test() {
+
+    }
+}
diff --git a/tests/fixtures/no-root-namespace-functions-single.php b/tests/fixtures/no-root-namespace-functions-single.php
new file mode 100644
index 0000000..e66f502
--- /dev/null
+++ b/tests/fixtures/no-root-namespace-functions-single.php
@@ -0,0 +1,14 @@
+<?php
+// @phpcsSniff CodeQuality.NoRootNamespaceFunctions
+
+class Foo
+{
+    function test() {
+
+    }
+}
+
+// @phpcsErrorOnNextLine
+function test() {
+
+}