diff --git a/composer.json b/composer.json
index 900cad93dc9..17e9fc9b9b6 100644
--- a/composer.json
+++ b/composer.json
@@ -59,7 +59,8 @@
             "Rector\\ContributorTools\\": "packages/ContributorTools/src",
             "Rector\\Laravel\\": "packages/Laravel/src",
             "Rector\\PhpSpecToPHPUnit\\": "packages/PhpSpecToPHPUnit/src",
-            "Rector\\Shopware\\": "packages/Shopware/src"
+            "Rector\\Shopware\\": "packages/Shopware/src",
+            "Rector\\NetteTesterToPHPUnit\\": "packages/NetteTesterToPHPUnit/src"
         }
     },
     "autoload-dev": {
@@ -90,7 +91,8 @@
             "Rector\\Laravel\\Tests\\": "packages/Laravel/tests",
             "Rector\\PhpSpecToPHPUnit\\Tests\\": "packages/PhpSpecToPHPUnit/tests",
             "Rector\\PHPStanExtensions\\": "utils/PHPStanExtensions/src",
-            "Rector\\Shopware\\Tests\\": "packages/Shopware/tests"
+            "Rector\\Shopware\\Tests\\": "packages/Shopware/tests",
+            "Rector\\NetteTesterToPHPUnit\\Tests\\": "packages/NetteTesterToPHPUnit/tests"
         },
         "classmap": [
             "packages/Symfony/tests/Rector/FrameworkBundle/AbstractToConstructorInjectionRectorSource",
@@ -106,7 +108,12 @@
         "symplify/easy-coding-standard": "Required to enable '--with-style' option. Use in case you don't have PHP_CodeSniffer or PHP-CS-Fixer yet."
     },
     "scripts": {
-        "complete-check": ["@check-cs", "phpunit", "@phpstan", "@update-docs"],
+        "complete-check": [
+            "@check-cs",
+            "phpunit",
+            "@phpstan",
+            "@update-docs"
+        ],
         "check-cs": "vendor/bin/ecs check bin packages src tests utils",
         "fix-cs": [
             "vendor/bin/ecs check bin packages src tests utils --fix",
@@ -124,4 +131,4 @@
     "config": {
         "sort-packages": true
     }
-}
+}
\ No newline at end of file
diff --git a/packages/ContributorTools/src/Command/CreateRectorCommand.php b/packages/ContributorTools/src/Command/CreateRectorCommand.php
index 7b77db41cf9..4e35157f8bb 100644
--- a/packages/ContributorTools/src/Command/CreateRectorCommand.php
+++ b/packages/ContributorTools/src/Command/CreateRectorCommand.php
@@ -3,6 +3,7 @@
 namespace Rector\ContributorTools\Command;
 
 use Nette\Utils\FileSystem;
+use Nette\Utils\Json;
 use Nette\Utils\Strings;
 use Rector\ContributorTools\Configuration\Configuration;
 use Rector\ContributorTools\Configuration\ConfigurationFactory;
@@ -84,6 +85,9 @@ final class CreateRectorCommand extends Command implements ContributorCommandInt
         $configuration = $this->configurationFactory->createFromConfigFile(getcwd() . '/create-rector.yaml');
         $templateVariables = $this->templateVariablesFactory->createFromConfiguration($configuration);
 
+        // setup psr-4 autoload, if not already in
+        $this->processComposerAutoload($templateVariables);
+
         foreach ($this->findTemplateFileInfos() as $smartFileInfo) {
             $destination = $this->resolveDestination($smartFileInfo, $templateVariables, $configuration);
 
@@ -209,4 +213,58 @@ final class CreateRectorCommand extends Command implements ContributorCommandInt
     {
         return str_replace(array_keys($variables), array_values($variables), $content);
     }
+
+    /**
+     * @param mixed[] $templateVariables
+     */
+    private function processComposerAutoload(array $templateVariables): void
+    {
+        $composerJsonContent = FileSystem::read(getcwd() . '/composer.json');
+        $composerJson = Json::decode($composerJsonContent, Json::FORCE_ARRAY);
+
+        $package = $templateVariables['_Package_'];
+
+        // already autoloaded?
+        if ($package === 'Rector') {
+            return;
+        }
+
+        $package = $templateVariables['_Package_'];
+        $namespace = 'Rector\\' . $package . '\\';
+        $namespaceTest = 'Rector\\' . $package . '\\Tests\\';
+
+        // already autoloaded?
+        if (isset($composerJson['autoload']['psr-4'][$namespace])) {
+            return;
+        }
+
+        $composerJson['autoload']['psr-4'][$namespace] = 'packages/' . $package . '/src';
+        $composerJson['autoload-dev']['psr-4'][$namespaceTest] = 'packages/' . $package . '/tests';
+
+        $composerJsonContent = Json::encode($composerJson, Json::PRETTY);
+
+        $composerJsonContent = $this->inlineSections($composerJsonContent, ['keywords', 'bin']);
+
+        // inline short arrays
+
+        FileSystem::write(getcwd() . '/composer.json', $composerJsonContent);
+    }
+
+    /**
+     * @param string[] $sections
+     */
+    private function inlineSections(string $jsonContent, array $sections): string
+    {
+        foreach ($sections as $section) {
+            $pattern = '#("' . preg_quote($section, '#') . '": )\[(.*?)\](,)#ms';
+            $jsonContent = Strings::replace($jsonContent, $pattern, function (array $match) {
+                $inlined = Strings::replace($match[2], '#\s+#', ' ');
+                $inlined = trim($inlined);
+                $inlined = '[' . $inlined . ']';
+                return $match[1] . $inlined . $match[3];
+            });
+        }
+
+        return $jsonContent;
+    }
 }