diff --git a/composer.json b/composer.json
index 749017e2..f19e5461 100644
--- a/composer.json
+++ b/composer.json
@@ -53,7 +53,7 @@
     },
     "scripts": {
         "cs-fix": "php-cs-fixer fix --path-mode=intersection --config=./.php_cs.dist --ansi .",
-		"cs-check": "php-cs-fixer fix --path-mode=intersection --config=.php_cs.dist --ansi --dry-run --diff --diff-format=udiff .",
+        "cs-check": "php-cs-fixer fix --path-mode=intersection --config=.php_cs.dist --ansi --dry-run --diff --diff-format=udiff .",
         "test": "atoum --force-terminal && ./vendor/bin/behat --suite pickle --colors"
     },
     "extra": {
@@ -66,6 +66,9 @@
             },
             "hoa/stream:1.17.02.21": {
                 "PHP 8 fixes": "patches/hoa/stream/0001-Fix-PHP-8-compatibility.patch"
+            },
+            "justinrainbow/json-schema:5.2.10": {
+                "PHP 8.1 fixes": "patches/justinrainbow/json-schema/0001-PHP-8.1-fixes.patch"
             }
         }
     }
diff --git a/composer.lock b/composer.lock
index 7faf197d..5d10cadd 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "e526bea65d4398661f2b5a1d775019f4",
+    "content-hash": "a2317f60486f9c09a0ee7258d7a2cf81",
     "packages": [
         {
             "name": "composer/ca-bundle",
@@ -432,6 +432,16 @@
             "extra": {
                 "branch-alias": {
                     "dev-master": "5.0.x-dev"
+                },
+                "patches_applied": {
+                    "hash": "32bf22d3205519a448f340cc8028bcedd09437b8",
+                    "list": [
+                        {
+                            "from-package": "friendsofphp/pickle dev-master",
+                            "path": "patches/justinrainbow/json-schema/0001-PHP-8.1-fixes.patch",
+                            "description": "PHP 8.1 fixes"
+                        }
+                    ]
                 }
             },
             "autoload": {
@@ -567,7 +577,6 @@
             "require-dev": {
                 "phpunit/phpunit": "^5.5|^6.0"
             },
-            "default-branch": true,
             "type": "library",
             "extra": {
                 "branch-alias": {
@@ -1789,6 +1798,16 @@
             "extra": {
                 "branch-alias": {
                     "dev-master": "3.x-dev"
+                },
+                "patches_applied": {
+                    "hash": "20651bf1016024344dfb3aeab39b19ee5389ddfa",
+                    "list": [
+                        {
+                            "from-package": "friendsofphp/pickle dev-master",
+                            "path": "patches/atoum/atoum/0001-PHP-8-fixes.patch",
+                            "description": "PHP 8 fixes"
+                        }
+                    ]
                 }
             },
             "autoload": {
@@ -3237,6 +3256,16 @@
             "extra": {
                 "branch-alias": {
                     "dev-master": "1.x-dev"
+                },
+                "patches_applied": {
+                    "hash": "f11d7d269a1fdc63edee82bffee61186c89e71af",
+                    "list": [
+                        {
+                            "from-package": "friendsofphp/pickle dev-master",
+                            "path": "patches/hoa/realdom/0001-Remove-use-of-deprecated-each-function.patch",
+                            "description": "PHP 8 fixes"
+                        }
+                    ]
                 }
             },
             "autoload": {
@@ -3434,6 +3463,16 @@
             "extra": {
                 "branch-alias": {
                     "dev-master": "1.x-dev"
+                },
+                "patches_applied": {
+                    "hash": "2486a6463faad73fe576c8964aa53d8fddd52e8a",
+                    "list": [
+                        {
+                            "from-package": "friendsofphp/pickle dev-master",
+                            "path": "patches/hoa/stream/0001-Fix-PHP-8-compatibility.patch",
+                            "description": "PHP 8 fixes"
+                        }
+                    ]
                 }
             },
             "autoload": {
diff --git a/patches/justinrainbow/json-schema/0001-PHP-8.1-fixes.patch b/patches/justinrainbow/json-schema/0001-PHP-8.1-fixes.patch
new file mode 100644
index 00000000..6ad97484
--- /dev/null
+++ b/patches/justinrainbow/json-schema/0001-PHP-8.1-fixes.patch
@@ -0,0 +1,20 @@
+From: Michele Locati <michele@locati.it>
+Date: Tue, 29 Jun 2021 18:08:46 +0200
+Subject: [PATCH] PHP 8.1 patched
+
+---
+ src/JsonSchema/Constraints/Constraint.php | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/JsonSchema/Constraints/Constraint.php b/src/JsonSchema/Constraints/Constraint.php
+--- a/src/JsonSchema/Constraints/Constraint.php
++++ b/src/JsonSchema/Constraints/Constraint.php
+@@ -45,7 +45,7 @@ abstract class Constraint extends BaseConstraint implements ConstraintInterface
+         $path = $path->withPropertyPaths(
+             array_merge(
+                 $path->getPropertyPaths(),
+-                array_filter(array($i), 'strlen')
++                array_filter(array((string) $i), 'strlen')
+             )
+         );
+