diff --git a/README.md b/README.md
index 4196273..e4cec1f 100644
--- a/README.md
+++ b/README.md
@@ -5,6 +5,7 @@
 [e]: https://www.php.net/manual/en/function.print-r.php
 [f]: https://github.com/symfony/var-exporter
 [g]: https://github.com/php-fig/log
+[h]: https://code.mensbeam.com/MensBeam/SelfSealingCallable
 
 # Catcher #
 
@@ -16,6 +17,7 @@ _Catcher_ uses classes called _handlers_ to handle throwables sent its way. PHP
 ## Requirements ##
 
 * PHP >= 8.1
+* [mensbeam/self-sealing-callable][h] ^1.0
 * [psr/log][g] ^3.0
 
 
diff --git a/composer.json b/composer.json
index 2886f06..18f11d9 100644
--- a/composer.json
+++ b/composer.json
@@ -21,7 +21,8 @@
     ],
     "require": {
         "php": ">=8.1",
-        "psr/log": "^3.0"
+        "psr/log": "^3.0",
+        "mensbeam/self-sealing-callable": "^1.0"
     },
     "require-dev": {
         "phpunit/phpunit": "^10",
diff --git a/composer.lock b/composer.lock
index 85f7678..f6e6bca 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,8 +4,51 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "016d5eec0db2855c94ebfb0c8a698b7a",
+    "content-hash": "653095595ffbfaf78354b0eb63a23283",
     "packages": [
+        {
+            "name": "mensbeam/self-sealing-callable",
+            "version": "v1.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/mensbeam/SelfSealingCallable.git",
+                "reference": "f3645a5f7745a8673d3a8ab23c0529ccdc793bde"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/mensbeam/SelfSealingCallable/zipball/f3645a5f7745a8673d3a8ab23c0529ccdc793bde",
+                "reference": "f3645a5f7745a8673d3a8ab23c0529ccdc793bde",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.1"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^11.0"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "MensBeam\\": "lib/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Dustin Wilson",
+                    "email": "dustin@dustinwilson.com"
+                }
+            ],
+            "description": "You won't find a better Self-Sealing Callable in this sector!",
+            "support": {
+                "issues": "https://github.com/mensbeam/SelfSealingCallable/issues",
+                "source": "https://github.com/mensbeam/SelfSealingCallable/tree/v1.0"
+            },
+            "time": "2024-02-12T16:55:01+00:00"
+        },
         {
             "name": "psr/log",
             "version": "3.0.0",
@@ -1866,5 +1909,5 @@
         "php": ">=8.1"
     },
     "platform-dev": [],
-    "plugin-api-version": "2.3.0"
+    "plugin-api-version": "2.6.0"
 }
diff --git a/lib/Catcher.php b/lib/Catcher.php
index 6586345..5e37034 100644
--- a/lib/Catcher.php
+++ b/lib/Catcher.php
@@ -38,12 +38,17 @@ class Catcher {
      * @var Handler[]
      */
     protected array $handlers = [];
+    /**
+     * Created when run for the first time and stores the shutdown handler;
+     * automatically disables itself when unregistered
+     */
+    protected static ?SelfSealingCallable $shutdownHandler = null;
     /** Flag set when the shutdown handler is run */
     protected bool $isShuttingDown = false;
-    /** Flag set when the class has registered error, exception, and shutdown handlers */
-    protected bool $registered = false;
     /** The last throwable handled by Catcher */
     protected ?\Throwable $lastThrowable = null;
+    /** Flag set when the class has registered error, exception, and shutdown handlers */
+    protected bool $registered = false;
 
 
 
@@ -110,7 +115,15 @@ class Catcher {
 
         set_error_handler([ $this, 'handleError' ]);
         set_exception_handler([ $this, 'handleThrowable' ]);
-        register_shutdown_function([ $this, 'handleShutdown' ]);
+
+        // Shutdown functions are fucky in php and can't be unset, so it is run in a
+        // SelfSealingCallable.
+        if (self::$shutdownHandler === null) {
+            self::$shutdownHandler = new SelfSealingCallable(fn() => $this->handleShutdown());
+            register_shutdown_function(self::$shutdownHandler);
+        }
+
+        self::$shutdownHandler->enable();
 
         $this->registered = true;
         return true;
@@ -136,6 +149,7 @@ class Catcher {
 
         restore_error_handler();
         restore_exception_handler();
+        self::$shutdownHandler->disable();
 
         // If error reporting has been set when registering and the error reporting level
         // is the same as it was when it was set then add E_ERROR back to the error