diff --git a/composer.json b/composer.json
index 9ae7d43d..5ca727a0 100644
--- a/composer.json
+++ b/composer.json
@@ -34,6 +34,7 @@
         "guzzlehttp/psr7": "^1.0 || ^2.0",
         "php-http/curl-client": "^2.0",
         "php-http/mock-client": "^1.0",
+        "phpcompatibility/php-compatibility": "dev-develop",
         "phpstan/phpstan": "~2.1",
         "phpunit/phpunit": "^9.5 || ^10.0",
         "slevomat/coding-standard": "^8.20",
diff --git a/composer.lock b/composer.lock
index 61d7f347..d6a5af90 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": "c71f76f0ed18fb72bfdab0b94774e240",
+    "content-hash": "893f04e6854aa23afd7dcd0cabfe1def",
     "packages": [
         {
             "name": "php-http/discovery",
@@ -1260,6 +1260,193 @@
             },
             "time": "2024-10-31T10:30:18+00:00"
         },
+        {
+            "name": "phpcompatibility/php-compatibility",
+            "version": "dev-develop",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/PHPCompatibility/PHPCompatibility.git",
+                "reference": "6e10469b0f3827862b37df2ac2b7ec4580ce888f"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/PHPCompatibility/PHPCompatibility/zipball/6e10469b0f3827862b37df2ac2b7ec4580ce888f",
+                "reference": "6e10469b0f3827862b37df2ac2b7ec4580ce888f",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.4",
+                "phpcsstandards/phpcsutils": "^1.1.0",
+                "squizlabs/php_codesniffer": "^3.13.0"
+            },
+            "replace": {
+                "wimg/php-compatibility": "*"
+            },
+            "require-dev": {
+                "php-parallel-lint/php-console-highlighter": "^1.0.0",
+                "php-parallel-lint/php-parallel-lint": "^1.4.0",
+                "phpcsstandards/phpcsdevcs": "^1.1.3",
+                "phpcsstandards/phpcsdevtools": "^1.2.0",
+                "phpunit/phpunit": "^4.8.36 || ^5.7.21 || ^6.0 || ^7.0 || ^8.0 || ^9.3.4 || ^10.5.32 || ^11.3.3",
+                "yoast/phpunit-polyfills": "^1.0.5 || ^2.0 || ^3.0"
+            },
+            "suggest": {
+                "roave/security-advisories": "dev-master || Helps prevent installing dependencies with known security issues."
+            },
+            "default-branch": true,
+            "type": "phpcodesniffer-standard",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "9.x-dev",
+                    "dev-develop": "10.x-dev"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "LGPL-3.0-or-later"
+            ],
+            "authors": [
+                {
+                    "name": "Wim Godden",
+                    "homepage": "https://github.com/wimg",
+                    "role": "lead"
+                },
+                {
+                    "name": "Juliette Reinders Folmer",
+                    "homepage": "https://github.com/jrfnl",
+                    "role": "lead"
+                },
+                {
+                    "name": "Contributors",
+                    "homepage": "https://github.com/PHPCompatibility/PHPCompatibility/graphs/contributors"
+                }
+            ],
+            "description": "A set of sniffs for PHP_CodeSniffer that checks for PHP cross-version compatibility.",
+            "homepage": "https://techblog.wimgodden.be/tag/codesniffer/",
+            "keywords": [
+                "compatibility",
+                "phpcs",
+                "standards",
+                "static analysis"
+            ],
+            "support": {
+                "issues": "https://github.com/PHPCompatibility/PHPCompatibility/issues",
+                "security": "https://github.com/PHPCompatibility/PHPCompatibility/security/policy",
+                "source": "https://github.com/PHPCompatibility/PHPCompatibility"
+            },
+            "funding": [
+                {
+                    "url": "https://github.com/PHPCompatibility",
+                    "type": "github"
+                },
+                {
+                    "url": "https://github.com/jrfnl",
+                    "type": "github"
+                },
+                {
+                    "url": "https://opencollective.com/php_codesniffer",
+                    "type": "open_collective"
+                },
+                {
+                    "url": "https://thanks.dev/u/gh/phpcompatibility",
+                    "type": "thanks_dev"
+                }
+            ],
+            "time": "2025-08-20T03:33:09+00:00"
+        },
+        {
+            "name": "phpcsstandards/phpcsutils",
+            "version": "1.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/PHPCSStandards/PHPCSUtils.git",
+                "reference": "f7eb16f2fa4237d5db9e8fed8050239bee17a9bd"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/PHPCSStandards/PHPCSUtils/zipball/f7eb16f2fa4237d5db9e8fed8050239bee17a9bd",
+                "reference": "f7eb16f2fa4237d5db9e8fed8050239bee17a9bd",
+                "shasum": ""
+            },
+            "require": {
+                "dealerdirect/phpcodesniffer-composer-installer": "^0.4.1 || ^0.5 || ^0.6.2 || ^0.7 || ^1.0",
+                "php": ">=5.4",
+                "squizlabs/php_codesniffer": "^3.13.0 || ^4.0"
+            },
+            "require-dev": {
+                "ext-filter": "*",
+                "php-parallel-lint/php-console-highlighter": "^1.0",
+                "php-parallel-lint/php-parallel-lint": "^1.4.0",
+                "phpcsstandards/phpcsdevcs": "^1.1.6",
+                "yoast/phpunit-polyfills": "^1.1.0 || ^2.0.0 || ^3.0.0"
+            },
+            "type": "phpcodesniffer-standard",
+            "extra": {
+                "branch-alias": {
+                    "dev-stable": "1.x-dev",
+                    "dev-develop": "1.x-dev"
+                }
+            },
+            "autoload": {
+                "classmap": [
+                    "PHPCSUtils/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "LGPL-3.0-or-later"
+            ],
+            "authors": [
+                {
+                    "name": "Juliette Reinders Folmer",
+                    "homepage": "https://github.com/jrfnl",
+                    "role": "lead"
+                },
+                {
+                    "name": "Contributors",
+                    "homepage": "https://github.com/PHPCSStandards/PHPCSUtils/graphs/contributors"
+                }
+            ],
+            "description": "A suite of utility functions for use with PHP_CodeSniffer",
+            "homepage": "https://phpcsutils.com/",
+            "keywords": [
+                "PHP_CodeSniffer",
+                "phpcbf",
+                "phpcodesniffer-standard",
+                "phpcs",
+                "phpcs3",
+                "phpcs4",
+                "standards",
+                "static analysis",
+                "tokens",
+                "utility"
+            ],
+            "support": {
+                "docs": "https://phpcsutils.com/",
+                "issues": "https://github.com/PHPCSStandards/PHPCSUtils/issues",
+                "security": "https://github.com/PHPCSStandards/PHPCSUtils/security/policy",
+                "source": "https://github.com/PHPCSStandards/PHPCSUtils"
+            },
+            "funding": [
+                {
+                    "url": "https://github.com/PHPCSStandards",
+                    "type": "github"
+                },
+                {
+                    "url": "https://github.com/jrfnl",
+                    "type": "github"
+                },
+                {
+                    "url": "https://opencollective.com/php_codesniffer",
+                    "type": "open_collective"
+                },
+                {
+                    "url": "https://thanks.dev/u/gh/phpcsstandards",
+                    "type": "thanks_dev"
+                }
+            ],
+            "time": "2025-08-10T01:04:45+00:00"
+        },
         {
             "name": "phpstan/phpdoc-parser",
             "version": "2.2.0",
@@ -3332,7 +3519,9 @@
     ],
     "aliases": [],
     "minimum-stability": "dev",
-    "stability-flags": {},
+    "stability-flags": {
+        "phpcompatibility/php-compatibility": 20
+    },
     "prefer-stable": true,
     "prefer-lowest": false,
     "platform": {
diff --git a/phpcs.xml.dist b/phpcs.xml.dist
index 45a481c3..2e49db44 100644
--- a/phpcs.xml.dist
+++ b/phpcs.xml.dist
@@ -21,6 +21,15 @@
     <!-- Use PSR-12 standard -->
     <rule ref="PSR12"/>
 
+    <!-- Check PHP 7.4 compatibility -->
+    <rule ref="PHPCompatibility">
+        <!-- Exclude functions that are polyfilled in src/polyfills.php -->
+        <exclude name="PHPCompatibility.FunctionUse.NewFunctions.array_is_listFound"/>
+        <exclude name="PHPCompatibility.FunctionUse.NewFunctions.str_containsFound"/>
+        <exclude name="PHPCompatibility.FunctionUse.NewFunctions.str_starts_withFound"/>
+        <exclude name="PHPCompatibility.FunctionUse.NewFunctions.str_ends_withFound"/>
+    </rule>
+
     <!-- Enforce namespace best practices -->
 	<rule ref="SlevomatCodingStandard.Namespaces.DisallowGroupUse" />
 	<rule ref="SlevomatCodingStandard.Namespaces.UseDoesNotStartWithBackslash" />
diff --git a/src/Providers/Http/DTO/Request.php b/src/Providers/Http/DTO/Request.php
index c896d024..bb015fb9 100644
--- a/src/Providers/Http/DTO/Request.php
+++ b/src/Providers/Http/DTO/Request.php
@@ -114,7 +114,7 @@ public function getUri(): string
     {
         // If GET request with data, append as query parameters
         if ($this->method === HttpMethodEnum::GET() && $this->data !== null && !empty($this->data)) {
-            $separator = strpos($this->uri, '?') === false ? '?' : '&';
+            $separator = str_contains($this->uri, '?') ? '&' : '?';
             return $this->uri . $separator . http_build_query($this->data);
         }
 
diff --git a/src/polyfills.php b/src/polyfills.php
index 51db0bed..dc5d5557 100644
--- a/src/polyfills.php
+++ b/src/polyfills.php
@@ -57,6 +57,26 @@ function str_starts_with(string $haystack, string $needle): bool
     }
 }
 
+if (!function_exists('str_contains')) {
+    /**
+     * Checks if a string contains a given substring.
+     *
+     * @since n.e.x.t
+     *
+     * @param string $haystack The string to search in.
+     * @param string $needle The substring to search for.
+     * @return bool True if $haystack contains $needle, false otherwise.
+     */
+    function str_contains(string $haystack, string $needle): bool
+    {
+        if ('' === $needle) {
+            return true;
+        }
+
+        return false !== strpos($haystack, $needle);
+    }
+}
+
 if (!function_exists('str_ends_with')) {
     /**
      * Checks if a string ends with a given substring.