diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..6e451fa
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,4 @@
+parameters:
+    level: 6
+    paths:
+        - src
diff --git a/src/Console/Command/ScanCommand.php b/src/Console/Command/ScanCommand.php
index 5aff13e..30b6408 100644
--- a/src/Console/Command/ScanCommand.php
+++ b/src/Console/Command/ScanCommand.php
@@ -16,7 +16,7 @@ use YakNet\AccessibilityConsole\Source\SourceLocator;
 
 class ScanCommand extends Command
 {
-    protected static $defaultName = 'scan';
+    protected static ?string $defaultName = 'scan';
 
     protected function configure(): void
     {
diff --git a/src/Core/Config.php b/src/Core/Config.php
index 7d59000..a115afe 100644
--- a/src/Core/Config.php
+++ b/src/Core/Config.php
@@ -4,8 +4,12 @@ namespace YakNet\AccessibilityConsole\Core;
 
 class Config
 {
+    /** @var array<string, mixed> */
     private array $settings = [];
 
+    /**
+     * @param array<string, mixed> $settings
+     */
     public function __construct(array $settings = [])
     {
         $this->settings = $settings;
diff --git a/src/Core/RuleEngine.php b/src/Core/RuleEngine.php
index cf4c0aa..f2dc10a 100644
--- a/src/Core/RuleEngine.php
+++ b/src/Core/RuleEngine.php
@@ -4,7 +4,7 @@ namespace YakNet\AccessibilityConsole\Core;
 
 class RuleEngine
 {
-    /** @var array */
+    /** @var array<int, mixed> */
     private array $rules = [];
 
     public function addRule(mixed $rule): void
diff --git a/src/Core/Violation.php b/src/Core/Violation.php
index 2690ee1..e3739f7 100644
--- a/src/Core/Violation.php
+++ b/src/Core/Violation.php
@@ -4,6 +4,9 @@ namespace YakNet\AccessibilityConsole\Core;
 
 class Violation
 {
+    /**
+     * @param array{file: string, line: int}|null $location
+     */
     public function __construct(
         public string $ruleId,
         public string $message,
@@ -14,6 +17,9 @@ class Violation
         public ?string $fixSuggestion = null
     ) {}
 
+    /**
+     * @return array{ruleId: string, message: string, severity: string, standard: string, htmlSnippet: string, location: array{file: string, line: int}|null, fixSuggestion: string|null}
+     */
     public function toArray(): array
     {
         return [
diff --git a/src/Rules/AriaRole.php b/src/Rules/AriaRole.php
index 40b2110..5c7134b 100644
--- a/src/Rules/AriaRole.php
+++ b/src/Rules/AriaRole.php
@@ -8,6 +8,7 @@ use YakNet\AccessibilityConsole\Core\WCAGStandard;
 
 class AriaRole extends AbstractRule
 {
+    /** @var array<int, string> */
     private static array $validRoles = [
         'alert', 'alertdialog', 'application', 'article', 'banner', 'button', 'cell', 'checkbox',
         'columnheader', 'combobox', 'complementary', 'contentinfo', 'definition', 'dialog', 'directory',
diff --git a/src/Rules/ColorContrast.php b/src/Rules/ColorContrast.php
index 008b95b..e1f227b 100644
--- a/src/Rules/ColorContrast.php
+++ b/src/Rules/ColorContrast.php
@@ -92,6 +92,9 @@ class ColorContrast extends AbstractRule
         return null;
     }
 
+    /**
+     * @return array{0: int, 1: int, 2: int}|null
+     */
     private function hexToRgb(string $hex): ?array
     {
         $hex = ltrim($hex, '#');
diff --git a/src/Source/SourceLocator.php b/src/Source/SourceLocator.php
index cbbb59e..11c01a3 100644
--- a/src/Source/SourceLocator.php
+++ b/src/Source/SourceLocator.php
@@ -8,12 +8,16 @@ use SplFileInfo;
 
 class SourceLocator
 {
+    /** @var array<int, string> */
     private array $extensions = ['php', 'html', 'twig', 'blade.php'];
 
     public function __construct(
         private readonly string $searchPath
     ) {}
 
+    /**
+     * @return array{file: string, line: int}|null
+     */
     public function locate(string $snippet): ?array
     {
         if (!is_dir($this->searchPath) || !is_readable($this->searchPath)) {
@@ -76,6 +80,9 @@ class SourceLocator
         return false;
     }
 
+    /**
+     * @return array{type: string, score?: float, location?: array{file: string, line: int}}
+     */
     private function searchInFile(string $filepath, string $searchSnippet, string $fullSnippet): array
     {
         $content = file_get_contents($filepath);
@@ -118,6 +125,9 @@ class SourceLocator
         return ['type' => 'none'];
     }
 
+    /**
+     * @return array{tag: string|null, attributes: array<string, string>}
+     */
     private function parseSnippet(string $snippet): array
     {
         preg_match('/<([a-zA-Z0-9]+)/', $snippet, $matches);
@@ -133,6 +143,9 @@ class SourceLocator
         return ['tag' => $tagName, 'attributes' => $attributes];
     }
 
+    /**
+     * @param array{tag: string|null, attributes: array<string, string>} $parsed
+     */
     private function calculateFuzzyScore(string $line, array $parsed): float
     {
         if (!$parsed['tag'] || !str_contains(strtolower($line), '<' . strtolower($parsed['tag']))) {