diff --git a/composer.json b/composer.json
index b64bc04..94f621a 100644
--- a/composer.json
+++ b/composer.json
@@ -27,7 +27,7 @@
         "vendor-dir": "vendor"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.5"
+        "phpunit/phpunit": "^10"
     },
     "scripts": {
         "test": "phpunit"
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index c216ef1..4ea85d6 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,14 +1,8 @@
 <?xml version="1.0"?>
-<phpunit
-        backupGlobals="false"
-        colors="true"
-        convertErrorsToExceptions="true"
-        convertNoticesToExceptions="true"
-        convertWarningsToExceptions="true"
->
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" backupGlobals="false" colors="true" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.5/phpunit.xsd" cacheDirectory=".phpunit.cache">
     <testsuites>
         <testsuite name="unit">
             <directory suffix="Test.php">./tests/</directory>
         </testsuite>
     </testsuites>
-</phpunit>
\ No newline at end of file
+</phpunit>
diff --git a/readme.md b/readme.md
index de3d862..5251215 100644
--- a/readme.md
+++ b/readme.md
@@ -43,6 +43,26 @@ $classes = \SH\AutoHook\ComposerJsonParser::getClasses($composerJsonPath);
 // Process classes to string
 [$output] = \SH\AutoHook\AttributeResolver::processClassesToString($classes);
 
+// Write to file
+(bool) $written = \SH\AutoHook\FileWriter::write($output, $outputPath);
+   ```
+
+### Advanced Usage
+
+Some projects may not have the composer.json available at runtime, so you can use the class loader object.
+
+#### Build/Wire Up
+
+  ```php
+// Get Classloader object
+$loader = require 'vendor/autoload.php';
+
+// Get the list of classes
+$classes = \SH\AutoHook\ComposerClassLoaderParser::getClasses($loader, ['App\\', 'MyNamespace\\']);
+
+// Process classes to string
+[$output] = \SH\AutoHook\AttributeResolver::processClassesToString($classes);
+
 // Write to file
 (bool) $written = \SH\AutoHook\FileWriter::write($output, $outputPath);
    ```
diff --git a/src/ComposerClassLoaderParser.php b/src/ComposerClassLoaderParser.php
new file mode 100644
index 0000000..664eb21
--- /dev/null
+++ b/src/ComposerClassLoaderParser.php
@@ -0,0 +1,68 @@
+<?php
+
+namespace SH\AutoHook;
+
+use \Composer\Autoload\ClassLoader;
+
+class ComposerClassLoaderParser
+{
+    /**
+     * Returns an array of classes in namespaces defined in the composer.json file.
+     *
+     * @param ClassLoader $classLoader
+     * @param array<string> $namespaces Since the classloader does not know which are project vs vendor namespaces, you can pass in an array of namespaces to filter by.
+     *
+     * @return array<string>
+     */
+    public static function getClasses(ClassLoader $classLoader, array $namespaces = []): array
+    {
+        ['namespaces' => $allNamespaces, 'classes' => $classes] = self::getNamespacesAndClasses($classLoader);
+
+        $namespaces = $namespaces ?: array_keys($allNamespaces);
+        $classes = array_keys($classes);
+
+        $matches = [];
+        foreach ($namespaces as $namespace) {
+            foreach ($classes as $key => $class) {
+                if (str_starts_with($class, $namespace)) {
+                    $matches[] = $class;
+
+                    unset($classes[$key]);
+                }
+            }
+        }
+
+        return $matches;
+    }
+
+    /**
+     * Returns an array with detailed information about namespaces and classes.
+     *
+     * Namespaces(k:namespace, v:paths array): map of namespaces and their absolute paths.
+     * Classes(k:class, v:path): map of classes and their absolute path.
+     *
+     * @return array{
+     * namespaces: array<string, array<string>>,
+     * classes: array<string, string>
+     * }
+     *
+     * Example:
+     * [
+     * 'namespaces' => [
+     * 'MyApp\\Controllers' => ['/Users/jphndpe/Project/src/Controllers/'],
+     * 'MyApp\\Models' => ['/Users/jphndpe/Project/src/Models/'],
+     * ],
+     * 'classes' => [
+     * 'MyApp\\Controllers\\HomeController' => '/Users/jphndpe/Project/src/Controllers/HomeController.php',
+     * 'MyApp\\Models\\UserModel' => '/Users/jphndpe/Project/src/Models/UserModel.php',
+     * ]
+     * ]
+     */
+    public static function getNamespacesAndClasses(ClassLoader $classLoader): array
+    {
+        return [
+            'namespaces' => $classLoader->getPrefixesPsr4(),
+            'classes'    => $classLoader->getClassMap()
+        ];
+    }
+}
\ No newline at end of file
diff --git a/tests/ComposerClassLoaderParserTest.php b/tests/ComposerClassLoaderParserTest.php
new file mode 100644
index 0000000..d511734
--- /dev/null
+++ b/tests/ComposerClassLoaderParserTest.php
@@ -0,0 +1,40 @@
+<?php
+
+namespace SH\AutoHook\Tests;
+
+use PHPUnit\Framework\TestCase;
+use \Composer\Autoload\ClassLoader;
+use SH\AutoHook\ComposerClassLoaderParser;
+
+class ComposerClassLoaderParserTest extends TestCase
+{
+    public function testGetClasses(): void
+    {
+        $classes = ComposerClassLoaderParser::getClasses(self::getClassLoader());
+
+        self::assertContains(ComposerClassLoaderParser::class, $classes);
+
+        $classes = ComposerClassLoaderParser::getClasses(self::getClassLoader(), ['SH\\AutoHook\\']);
+
+        self::assertContains(ComposerClassLoaderParser::class, $classes);
+    }
+
+    public function testGetNamespacesAndClasses(): void
+    {
+        ['namespaces' => $namespaces, 'classes' => $classes] = ComposerClassLoaderParser::getNamespacesAndClasses(self::getClassLoader());
+
+        self::assertArrayHasKey('SH\\AutoHook\\', $namespaces);
+        self::assertArrayHasKey(ComposerClassLoaderParser::class, $classes);
+    }
+
+    private static function getClassLoader(): ClassLoader
+    {
+        static $classLoader;
+
+        if (null === $classLoader) {
+            $classLoader = require __DIR__.'/../vendor/autoload.php';
+        }
+
+        return $classLoader;
+    }
+}
\ No newline at end of file