diff --git a/composer.json b/composer.json
index db15e75a..dfcf7c17 100644
--- a/composer.json
+++ b/composer.json
@@ -23,7 +23,7 @@
     "require": {
         "php": "^7.2 || ^8.0",
         "dealerdirect/phpcodesniffer-composer-installer": "^0.6.2 || ^0.7",
-        "slevomat/coding-standard": "^8.5.1",
+        "slevomat/coding-standard": "^8.6",
         "squizlabs/php_codesniffer": "^3.7"
     },
     "config": {
diff --git a/lib/Doctrine/ruleset.xml b/lib/Doctrine/ruleset.xml
index 05a0d89c..2c5a109e 100644
--- a/lib/Doctrine/ruleset.xml
+++ b/lib/Doctrine/ruleset.xml
@@ -110,6 +110,14 @@
     <rule ref="PSR2.ControlStructures.ElseIfDeclaration.NotAllowed">
         <type>error</type>
     </rule>
+    <!-- Disallow multiple attributes inside one #[] -->
+    <rule ref="SlevomatCodingStandard.Attributes.DisallowAttributesJoining"/>
+    <!-- Require only one attribute per line -->
+    <rule ref="SlevomatCodingStandard.Attributes.DisallowMultipleAttributesPerLine"/>
+    <!-- Attributes should be adjoined to the PHP element they belong to -->
+    <rule ref="SlevomatCodingStandard.Attributes.AttributeAndTargetSpacing"/>
+    <!-- Require PHPDoc always before attributes -->
+    <rule ref="SlevomatCodingStandard.Attributes.RequireAttributeAfterDocComment"/>
     <!-- Require that single line arrays have the correct spacing: no space around brackets and one space after comma -->
     <rule ref="SlevomatCodingStandard.Arrays.SingleLineArrayWhitespace"/>
     <!-- Require comma after last element in multi-line array -->
diff --git a/tests/expected_report.txt b/tests/expected_report.txt
index de60dbe3..9e34caa5 100644
--- a/tests/expected_report.txt
+++ b/tests/expected_report.txt
@@ -6,6 +6,7 @@ FILE                                                  ERRORS  WARNINGS
 tests/input/array_indentation.php                     10      0
 tests/input/arrow-functions-format.php                10      0
 tests/input/assignment-operators.php                  4       0
+tests/input/attributes.php                            15      0
 tests/input/binary_operators.php                      9       0
 tests/input/class-references.php                      10      0
 tests/input/ClassPropertySpacing.php                  2       0
@@ -51,9 +52,9 @@ tests/input/use-ordering.php                          1       0
 tests/input/useless-semicolon.php                     2       0
 tests/input/UselessConditions.php                     21      0
 ----------------------------------------------------------------------
-A TOTAL OF 437 ERRORS AND 0 WARNINGS WERE FOUND IN 47 FILES
+A TOTAL OF 452 ERRORS AND 0 WARNINGS WERE FOUND IN 48 FILES
 ----------------------------------------------------------------------
-PHPCBF CAN FIX 370 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
+PHPCBF CAN FIX 374 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
 ----------------------------------------------------------------------
 
 
diff --git a/tests/fixed/attributes.php b/tests/fixed/attributes.php
new file mode 100644
index 00000000..2fcb6cc9
--- /dev/null
+++ b/tests/fixed/attributes.php
@@ -0,0 +1,32 @@
+<?php
+
+declare(strict_types=1);
+
+#[Attribute1]
+#[Attribute2]
+#[Attribute3]
+class TestClass
+{
+}
+
+#[Attribute1]
+#[Attribute2]
+#[Attribute3]
+class TestClass2
+{
+}
+
+#[Attribute1]
+#[Attribute2]
+#[Attribute3]
+class TestClass3
+{
+}
+
+/** @internal */
+#[Attribute1]
+#[Attribute2]
+#[Attribute3]
+class TestClass4
+{
+}
diff --git a/tests/input/attributes.php b/tests/input/attributes.php
new file mode 100644
index 00000000..83d4c399
--- /dev/null
+++ b/tests/input/attributes.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+#[Attribute1] #[Attribute2]
+#[Attribute3]
+class TestClass
+{
+}
+
+#[Attribute1,Attribute2]
+#[Attribute3]
+class TestClass2
+{
+}
+
+#[Attribute1]
+#[Attribute2]
+#[Attribute3]
+
+class TestClass3
+{
+}
+
+#[Attribute1]
+#[Attribute2]
+#[Attribute3]
+/** @internal */
+class TestClass4
+{
+}
diff --git a/tests/php72-compatibility.patch b/tests/php72-compatibility.patch
index d200bb3e..01281c45 100644
--- a/tests/php72-compatibility.patch
+++ b/tests/php72-compatibility.patch
@@ -1,8 +1,8 @@
 diff --git a/tests/expected_report.txt b/tests/expected_report.txt
-index 151bce4..0afca8c 100644
+index 9e34caa..ea3b611 100644
 --- a/tests/expected_report.txt
 +++ b/tests/expected_report.txt
-@@ -14,26 +14,23 @@ tests/input/constants-var.php                         7       0
+@@ -16,26 +16,23 @@ tests/input/constants-var.php                         7       0
  tests/input/ControlStructures.php                     28      0
  tests/input/doc-comment-spacing.php                   11      0
  tests/input/duplicate-assignment-variable.php         1       0
@@ -37,7 +37,7 @@ index 151bce4..0afca8c 100644
  tests/input/semicolon_spacing.php                     3       0
  tests/input/single-line-array-spacing.php             5       0
  tests/input/spread-operator.php                       6       0
-@@ -42,17 +39,16 @@ tests/input/strings.php                               1       0
+@@ -44,17 +41,16 @@ tests/input/strings.php                               1       0
  tests/input/superfluous-naming.php                    11      0
  tests/input/test-case.php                             8       0
  tests/input/trailing_comma_on_array.php               1       0
@@ -51,11 +51,11 @@ index 151bce4..0afca8c 100644
 -tests/input/UselessConditions.php                     21      0
 +tests/input/UselessConditions.php                     20      0
  ----------------------------------------------------------------------
--A TOTAL OF 437 ERRORS AND 0 WARNINGS WERE FOUND IN 47 FILES
-+A TOTAL OF 390 ERRORS AND 0 WARNINGS WERE FOUND IN 43 FILES
+-A TOTAL OF 452 ERRORS AND 0 WARNINGS WERE FOUND IN 48 FILES
++A TOTAL OF 405 ERRORS AND 0 WARNINGS WERE FOUND IN 44 FILES
  ----------------------------------------------------------------------
--PHPCBF CAN FIX 370 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
-+PHPCBF CAN FIX 323 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
+-PHPCBF CAN FIX 374 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
++PHPCBF CAN FIX 327 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
  ----------------------------------------------------------------------
  
  
diff --git a/tests/php73-compatibility.patch b/tests/php73-compatibility.patch
index 6b28d34e..a5244597 100644
--- a/tests/php73-compatibility.patch
+++ b/tests/php73-compatibility.patch
@@ -1,8 +1,8 @@
 diff --git a/tests/expected_report.txt b/tests/expected_report.txt
-index 151bce4..94718eb 100644
+index 9e34caa..c5062cb 100644
 --- a/tests/expected_report.txt
 +++ b/tests/expected_report.txt
-@@ -14,26 +14,23 @@ tests/input/constants-var.php                         7       0
+@@ -16,26 +16,23 @@ tests/input/constants-var.php                         7       0
  tests/input/ControlStructures.php                     28      0
  tests/input/doc-comment-spacing.php                   11      0
  tests/input/duplicate-assignment-variable.php         1       0
@@ -37,7 +37,7 @@ index 151bce4..94718eb 100644
  tests/input/semicolon_spacing.php                     3       0
  tests/input/single-line-array-spacing.php             5       0
  tests/input/spread-operator.php                       6       0
-@@ -42,17 +39,17 @@ tests/input/strings.php                               1       0
+@@ -44,17 +41,17 @@ tests/input/strings.php                               1       0
  tests/input/superfluous-naming.php                    11      0
  tests/input/test-case.php                             8       0
  tests/input/trailing_comma_on_array.php               1       0
@@ -52,11 +52,11 @@ index 151bce4..94718eb 100644
 -tests/input/UselessConditions.php                     21      0
 +tests/input/UselessConditions.php                     20      0
  ----------------------------------------------------------------------
--A TOTAL OF 437 ERRORS AND 0 WARNINGS WERE FOUND IN 47 FILES
-+A TOTAL OF 392 ERRORS AND 0 WARNINGS WERE FOUND IN 44 FILES
+-A TOTAL OF 452 ERRORS AND 0 WARNINGS WERE FOUND IN 48 FILES
++A TOTAL OF 407 ERRORS AND 0 WARNINGS WERE FOUND IN 45 FILES
  ----------------------------------------------------------------------
--PHPCBF CAN FIX 370 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
-+PHPCBF CAN FIX 325 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
+-PHPCBF CAN FIX 374 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
++PHPCBF CAN FIX 329 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
  ----------------------------------------------------------------------
  
  
diff --git a/tests/php74-compatibility.patch b/tests/php74-compatibility.patch
index be50dc5c..62927f8c 100644
--- a/tests/php74-compatibility.patch
+++ b/tests/php74-compatibility.patch
@@ -1,8 +1,8 @@
 diff --git a/tests/expected_report.txt b/tests/expected_report.txt
-index 151bce4..08a098f 100644
+index 9e34caa..ed67841 100644
 --- a/tests/expected_report.txt
 +++ b/tests/expected_report.txt
-@@ -14,26 +14,23 @@ tests/input/constants-var.php                         7       0
+@@ -16,26 +16,23 @@ tests/input/constants-var.php                         7       0
  tests/input/ControlStructures.php                     28      0
  tests/input/doc-comment-spacing.php                   11      0
  tests/input/duplicate-assignment-variable.php         1       0
@@ -35,7 +35,7 @@ index 151bce4..08a098f 100644
  tests/input/semicolon_spacing.php                     3       0
  tests/input/single-line-array-spacing.php             5       0
  tests/input/spread-operator.php                       6       0
-@@ -42,17 +39,17 @@ tests/input/strings.php                               1       0
+@@ -44,17 +41,17 @@ tests/input/strings.php                               1       0
  tests/input/superfluous-naming.php                    11      0
  tests/input/test-case.php                             8       0
  tests/input/trailing_comma_on_array.php               1       0
@@ -50,11 +50,11 @@ index 151bce4..08a098f 100644
 -tests/input/UselessConditions.php                     21      0
 +tests/input/UselessConditions.php                     20      0
  ----------------------------------------------------------------------
--A TOTAL OF 437 ERRORS AND 0 WARNINGS WERE FOUND IN 47 FILES
-+A TOTAL OF 401 ERRORS AND 0 WARNINGS WERE FOUND IN 44 FILES
+-A TOTAL OF 452 ERRORS AND 0 WARNINGS WERE FOUND IN 48 FILES
++A TOTAL OF 416 ERRORS AND 0 WARNINGS WERE FOUND IN 45 FILES
  ----------------------------------------------------------------------
--PHPCBF CAN FIX 370 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
-+PHPCBF CAN FIX 334 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
+-PHPCBF CAN FIX 374 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
++PHPCBF CAN FIX 338 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
  ----------------------------------------------------------------------
  
  
diff --git a/tests/php80-compatibility.patch b/tests/php80-compatibility.patch
index f47b0c7f..a5e229ee 100644
--- a/tests/php80-compatibility.patch
+++ b/tests/php80-compatibility.patch
@@ -1,8 +1,8 @@
 diff --git a/tests/expected_report.txt b/tests/expected_report.txt
-index 151bce4..873691d 100644
+index 9e34caa..71022c4 100644
 --- a/tests/expected_report.txt
 +++ b/tests/expected_report.txt
-@@ -16,7 +16,6 @@ tests/input/doc-comment-spacing.php                   11      0
+@@ -18,7 +18,6 @@ tests/input/doc-comment-spacing.php                   11      0
  tests/input/duplicate-assignment-variable.php         1       0
  tests/input/EarlyReturn.php                           7       0
  tests/input/example-class.php                         47      0
@@ -10,7 +10,7 @@ index 151bce4..873691d 100644
  tests/input/Exceptions.php                            1       0
  tests/input/forbidden-comments.php                    14      0
  tests/input/forbidden-functions.php                   6       0
-@@ -31,7 +30,7 @@ tests/input/null_coalesce_equal_operator.php          5       0
+@@ -33,7 +32,7 @@ tests/input/null_coalesce_equal_operator.php          5       0
  tests/input/null_coalesce_operator.php                3       0
  tests/input/null_safe_operator.php                    1       0
  tests/input/optimized-functions.php                   1       0
@@ -19,15 +19,15 @@ index 151bce4..873691d 100644
  tests/input/return_type_on_closures.php               26      0
  tests/input/return_type_on_methods.php                22      0
  tests/input/semicolon_spacing.php                     3       0
-@@ -50,9 +49,9 @@ tests/input/use-ordering.php                          1       0
+@@ -52,9 +51,9 @@ tests/input/use-ordering.php                          1       0
  tests/input/useless-semicolon.php                     2       0
  tests/input/UselessConditions.php                     21      0
  ----------------------------------------------------------------------
--A TOTAL OF 437 ERRORS AND 0 WARNINGS WERE FOUND IN 47 FILES
-+A TOTAL OF 431 ERRORS AND 0 WARNINGS WERE FOUND IN 46 FILES
+-A TOTAL OF 452 ERRORS AND 0 WARNINGS WERE FOUND IN 48 FILES
++A TOTAL OF 446 ERRORS AND 0 WARNINGS WERE FOUND IN 47 FILES
  ----------------------------------------------------------------------
--PHPCBF CAN FIX 370 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
-+PHPCBF CAN FIX 364 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
+-PHPCBF CAN FIX 374 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
++PHPCBF CAN FIX 368 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
  ----------------------------------------------------------------------