diff --git a/.github/FUNDING b/.github/FUNDING
index 0dcac02..7635e8b 100644
--- a/.github/FUNDING
+++ b/.github/FUNDING
@@ -1 +1 @@
-ko_fi: sammyjo20
+github: sammyjo20
diff --git a/.github/workflows/phpstan.yml b/.github/workflows/phpstan.yml
index 8ad0db3..c1e626f 100644
--- a/.github/workflows/phpstan.yml
+++ b/.github/workflows/phpstan.yml
@@ -18,7 +18,7 @@ jobs:
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: '8.1'
+          php-version: '8.4'
           coverage: none
 
       - name: Install composer dependencies
diff --git a/.github/workflows/redis-tests.yml b/.github/workflows/redis-tests.yml
index d42b7e6..9e54899 100644
--- a/.github/workflows/redis-tests.yml
+++ b/.github/workflows/redis-tests.yml
@@ -18,7 +18,7 @@ jobs:
       fail-fast: true
       matrix:
         os: [ ubuntu-latest ]
-        php: [ 8.1, 8.2 ]
+        php: [ 8.1, 8.2, 8.3, 8.4 ]
         stability: [ prefer-lowest, prefer-stable ]
     services:
       # Label used to access the service container
@@ -39,7 +39,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 821e41d..c908e0e 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -18,14 +18,14 @@ jobs:
       fail-fast: true
       matrix:
         os: [ ubuntu-latest, windows-latest ]
-        php: [ 8.1, 8.2 ]
+        php: [ 8.1, 8.2, 8.3, 8.4 ]
         stability: [ prefer-lowest, prefer-stable ]
 
     name: P${{ matrix.php }} - ${{ matrix.stability }} - ${{ matrix.os }}
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
diff --git a/.gitignore b/.gitignore
index 7d655ba..a11142a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,6 +14,7 @@
 # Caches, externally stored stuff, etc
 .php-cs-fixer.cache
 .phpunit.result.cache
+.phpunit.cache
 tests/Fixtures/Saloon
 
 # environments/configs
diff --git a/composer.json b/composer.json
index 05181d6..b47efdb 100644
--- a/composer.json
+++ b/composer.json
@@ -26,6 +26,7 @@
         "orchestra/testbench": "^8.5"
     },
     "minimum-stability": "stable",
+    "prefer-stable": true,
     "autoload": {
         "psr-4": {
             "Saloon\\RateLimitPlugin\\": "src/",
diff --git a/src/Limit.php b/src/Limit.php
index dc5fbe0..41ccc54 100644
--- a/src/Limit.php
+++ b/src/Limit.php
@@ -4,7 +4,6 @@
 
 namespace Saloon\RateLimitPlugin;
 
-use Closure;
 use DateInterval;
 use DateTimeImmutable;
 use Saloon\Http\Response;
@@ -40,7 +39,7 @@ class Limit
     /**
      * The threshold that should be used when determining if a limit has been reached
      *
-     * Must be between 0 and 1. For example if you want the limiter to kick in at 85%
+     * Must be between 0 and 1. For example, if you want the limiter to kick in at 85%
      * you must set the threshold to 0.85
      */
     protected float $threshold = 1;
@@ -58,8 +57,10 @@ class Limit
 
     /**
      * Custom response handler
+     *
+     * @var null|callable(): mixed
      */
-    protected ?Closure $responseHandler = null;
+    protected $responseHandler = null;
 
     /**
      * Determines if we should sleep or not
@@ -69,15 +70,15 @@ class Limit
     /**
      * @param (callable(): mixed)|null $responseHandler
      */
-    final public function __construct(int $allow, float $threshold = 1, callable $responseHandler = null)
+    final public function __construct(int $allow, float $threshold = 1, ?callable $responseHandler = null)
     {
         $this->allow = $allow;
         $this->threshold = $threshold;
-        $this->responseHandler = isset($responseHandler) ? $responseHandler(...) : null;
+        $this->responseHandler = $responseHandler;
     }
 
     /**
-     * Construct a limiter's allow and threshold
+     * Construct a limiter's allowing and threshold
      */
     public static function allow(int $requests, float $threshold = 1): static
     {
@@ -89,7 +90,7 @@ public static function allow(int $requests, float $threshold = 1): static
      */
     public static function custom(callable $responseHandler): static
     {
-        return (new static(1, 1, $responseHandler(...)))->everySeconds(60, 'custom');
+        return (new static(1, 1, $responseHandler))->everySeconds(60, 'custom');
     }
 
     /**
@@ -123,7 +124,7 @@ public function hit(int $amount = 1): static
     /**
      * Set the limit as exceeded
      */
-    public function exceeded(int $releaseInSeconds = null): void
+    public function exceeded(?int $releaseInSeconds = null): void
     {
         $this->exceeded = true;
 
@@ -281,7 +282,7 @@ public function handleResponse(Response $response): void
      *
      * @return $this
      * @throws \JsonException
-     * @throws \Saloon\RateLimitPlugin\Exceptions\LimitException
+     * @throws LimitException
      */
     public function update(RateLimitStore $store): static
     {
@@ -316,14 +317,14 @@ public function update(RateLimitStore $store): static
             return $this;
         }
 
-        // If our expiry hasn't passed, yet then we'll set the expiry timestamp
-        // and, we'll also update the hits so the current instance has the
+        // If our expiry hasn't passed yet, then we'll set the expiry timestamp,
+        // and we'll also update the hits so the current instance has the
         // number of previous hits.
 
         $this->setExpiryTimestamp($expiry);
         $this->hit($hits);
 
-        // If this is a fromResponse limiter then we should apply the "allow" which will
+        // If this is a fromResponse limiter, then we should apply the "allow" which will
         // be useful to check if we have reached our rate limit
 
         if ($this->usesResponse()) {
@@ -338,7 +339,7 @@ public function update(RateLimitStore $store): static
      *
      * @return $this
      * @throws \JsonException
-     * @throws \Saloon\RateLimitPlugin\Exceptions\LimitException
+     * @throws LimitException
      */
     public function save(RateLimitStore $store, int $resetHits = 1): static
     {