diff --git a/src/Command/LatexTestCommand.php b/src/Command/LatexTestCommand.php
index 7055ec9..9527ded 100644
--- a/src/Command/LatexTestCommand.php
+++ b/src/Command/LatexTestCommand.php
@@ -22,7 +22,7 @@ public function __construct(private readonly LatexGeneratorInterface $latexGener
     parent::__construct();
   }
 
-  protected function configure() {
+  protected function configure(): void {
     $this
         ->setName('bobv:latex:test')
         ->setDescription('Generate a test LaTeX file (+ pdf)')
@@ -56,6 +56,6 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 
     $output->writeln($generatedLocation);
 
-    return 0; // Success
+    return Command::SUCCESS;
   }
 }
diff --git a/src/DependencyInjection/BobvLatexExtension.php b/src/DependencyInjection/BobvLatexExtension.php
index a660fea..dc1ba5c 100644
--- a/src/DependencyInjection/BobvLatexExtension.php
+++ b/src/DependencyInjection/BobvLatexExtension.php
@@ -9,17 +9,9 @@
 use Symfony\Component\HttpKernel\DependencyInjection\Extension;
 use Symfony\Component\String\UnicodeString;
 
-/**
- * This is the class that loads and manages your bundle configuration
- *
- * To learn more see {@link http://symfony.com/doc/current/cookbook/bundles/extension.html}
- */
 class BobvLatexExtension extends Extension
 {
-  /**
-   * {@inheritDoc}
-   */
-  public function load(array $configs, ContainerBuilder $container) {
+  public function load(array $configs, ContainerBuilder $container): void {
     $configuration = new Configuration();
     $config        = $this->processConfiguration($configuration, $configs);
 
diff --git a/src/DependencyInjection/Configuration.php b/src/DependencyInjection/Configuration.php
index b91b6ae..2457719 100644
--- a/src/DependencyInjection/Configuration.php
+++ b/src/DependencyInjection/Configuration.php
@@ -5,17 +5,8 @@
 use Symfony\Component\Config\Definition\Builder\TreeBuilder;
 use Symfony\Component\Config\Definition\ConfigurationInterface;
 
-/**
- * This is the class that validates and merges configuration from your app/config files
- *
- * To learn more see
- * {@link http://symfony.com/doc/current/cookbook/bundles/extension.html#cookbook-bundles-extension-config-class}
- */
 class Configuration implements ConfigurationInterface
 {
-  /**
-   * {@inheritDoc}
-   */
   public function getConfigTreeBuilder(): TreeBuilder {
     $treeBuilder = new TreeBuilder('bobv_latex');
 
diff --git a/src/Exception/BibliographyGenerationException.php b/src/Exception/BibliographyGenerationException.php
index cb1d30f..83b56d0 100644
--- a/src/Exception/BibliographyGenerationException.php
+++ b/src/Exception/BibliographyGenerationException.php
@@ -6,14 +6,8 @@
 
 class BibliographyGenerationException extends LatexException
 {
-
-  /**
-   * @param string      $texLocation
-   * @param int         $exitCode
-   * @param string|null $exitCodeText
-   */
-  public function __construct($texLocation, $exitCode, $exitCodeText = NULL) {
-    if ($exitCodeText !== NULL) {
+  public function __construct(string $texLocation, int $exitCode, ?string $exitCodeText = null) {
+    if ($exitCodeText !== null) {
       $exitCodeText = sprintf(' (%s)', $exitCodeText);
     } else {
       $exitCodeText = '';
diff --git a/src/Exception/ImageNotFoundException.php b/src/Exception/ImageNotFoundException.php
index bb072ab..4a58315 100644
--- a/src/Exception/ImageNotFoundException.php
+++ b/src/Exception/ImageNotFoundException.php
@@ -3,24 +3,16 @@
 namespace Bobv\LatexBundle\Exception;
 
 /**
- * Class ImageNotFoundException
  * Simple \Exception extend for better error origin check
  */
 class ImageNotFoundException extends \Exception
 {
-  private $imageLocation;
-
-  public function __construct($imageLocation)
+  public function __construct(private readonly string $imageLocation)
   {
-    $this->imageLocation = $imageLocation;
-
     parent::__construct("The image used is not found. Did you provide the complete path? (provided path = $imageLocation)");
   }
 
-  /**
-   * @return mixed
-   */
-  public function getImageLocation()
+  public function getImageLocation(): string
   {
     return $this->imageLocation;
   }
diff --git a/src/Exception/LatexException.php b/src/Exception/LatexException.php
index 312810c..b725cc1 100644
--- a/src/Exception/LatexException.php
+++ b/src/Exception/LatexException.php
@@ -3,9 +3,8 @@
 namespace Bobv\LatexBundle\Exception;
 
 /**
- * Class LatexException
  * Simple \Exception extend for better error origin check
  */
-class LatexException extends \Exception{
-
+class LatexException extends \Exception
+{
 }
diff --git a/src/Exception/LatexNotImplementedException.php b/src/Exception/LatexNotImplementedException.php
index 2018837..2de5679 100644
--- a/src/Exception/LatexNotImplementedException.php
+++ b/src/Exception/LatexNotImplementedException.php
@@ -3,9 +3,8 @@
 namespace Bobv\LatexBundle\Exception;
 
 /**
- * Class LatexNotImplementedException
  * Simple \Exception extend for better error origin check
  */
-class LatexNotImplementedException extends LatexException{
-
+class LatexNotImplementedException extends LatexException
+{
 }
diff --git a/src/Exception/LatexParseException.php b/src/Exception/LatexParseException.php
index 60dd33b..b5da14d 100644
--- a/src/Exception/LatexParseException.php
+++ b/src/Exception/LatexParseException.php
@@ -3,32 +3,24 @@
 namespace Bobv\LatexBundle\Exception;
 
 /**
- * Class LatexException
  * Simple \Exception extend for better error origin check
  */
 class LatexParseException extends LatexException
 {
-
-
   const LOG_GET_LINES = 4;
   const LOG_MAX_LINES = 10;
   const TEX_GET_LINES = 8;
   const TEX_MAX_LINES = 20;
 
-  protected $filteredTexSource = array();
+  protected array $filteredTexSource = [];
 
-  protected $filteredLogSource = array();
+  protected array $filteredLogSource = [];
 
-  /**
-   * @param string     $texLocation
-   * @param int        $exitCode
-   * @param array|NULL $pdfLatexOutput
-   */
-  public function __construct($texLocation, $exitCode, array $pdfLatexOutput = NULL, $exitCodeText = NULL)
+  public function __construct(string $texLocation, int $exitCode, ?array $pdfLatexOutput = null, ?string $exitCodeText = null)
   {
-    if($exitCodeText !== NULL){
+    if ($exitCodeText !== null) {
       $exitCodeText = sprintf(' (%s)', $exitCodeText);
-    }else{
+    } else {
       $exitCodeText = '';
     }
 
@@ -41,10 +33,8 @@ public function __construct($texLocation, $exitCode, array $pdfLatexOutput = NUL
 
   /**
    * Return an extended error message together with the extracted errors
-   *
-   * @return string
    */
-  public function getExtendedMessage()
+  public function getExtendedMessage(): string
   {
     $message = $this->getMessage();
 
@@ -57,28 +47,24 @@ public function getExtendedMessage()
   }
 
   /**
-   * Try to find usefull information on the error that has occurred
-   *
-   * @param array  $errorOutput
-   * @param string $texLocation
-   *
-   * @return array Contains the filtered output which should only contain information about the errors
+   * Try to find useful information on the error that has occurred
+   * This is stored in the object properties $filteredLogSource and $filteredTexSource
    */
-  protected function findErrors(array $errorOutput, $texLocation = NULL)
+  protected function findErrors(array $errorOutput, ?string $texLocation = NULL): void
   {
     $refWarning       = strtolower('LaTeX Warning: Reference');
-    $filteredErrors   = array();
-    $filteredErrors[] = "---";
+    $filteredErrors   = [];
+    $filteredErrors[] = '---';
 
     array_walk($errorOutput, function ($value, $key) use (&$errorOutput, &$texLocation, &$filteredErrors, $refWarning) {
 
       // Find lines with an error
       if (preg_match_all('/error|missing|not found|undefined|too many|runaway|\$|you can\'t use|invalid/ui', $value) > 0) {
-        if (substr(strtolower($errorOutput[$key]), 0, strlen($refWarning)) !== $refWarning) {
+        if (!str_starts_with(strtolower($errorOutput[$key]), $refWarning)) {
           // Get the lines surrounding the error, but do not include empty lines
 
           // Get lines before the error
-          $temp = array();
+          $temp = [];
           for ($count = 0, $i = 0; $count < self::LOG_GET_LINES && $i < self::LOG_MAX_LINES; $i++) {
             if (isset($errorOutput[$key - $i])) {
               $value = trim(preg_replace('/\s+/', ' ', $errorOutput[$key - $i]));
@@ -105,7 +91,7 @@ protected function findErrors(array $errorOutput, $texLocation = NULL)
             }
           }
 
-          $filteredErrors[] = "---";
+          $filteredErrors[] = '---';
         }
       }
 
@@ -116,16 +102,16 @@ protected function findErrors(array $errorOutput, $texLocation = NULL)
 
     // Try to find matching tex lines
     // Check if a line number can be found in the errors
-    $this->filteredTexSource[] = "---";
+    $this->filteredTexSource[] = '---';
     if ($texLocation !== NULL) {
-      $lineNumber = array();
+      $lineNumber = [];
       $texFile    = new \SplFileObject($texLocation);
       foreach ($this->filteredLogSource as $logLine) {
         preg_match('/l\.(\d+)/ui', $logLine, $lineNumber);
         if (count($lineNumber) == 2) {
 
           // Get lines before the linenumber
-          $temp = array();
+          $temp = [];
           for ($count = 0, $i = 0; $count < self::TEX_GET_LINES && $i < self::TEX_MAX_LINES; $i++) {
             $texFile->seek($lineNumber[1] - $i);
             if ($texFile->valid()) {
@@ -138,7 +124,7 @@ protected function findErrors(array $errorOutput, $texLocation = NULL)
               break;
             }
           }
-          $this->filteredTexSource = array_merge($this->filteredTexSource, array($lineNumber[0]), array_reverse($temp));
+          $this->filteredTexSource = array_merge($this->filteredTexSource, [$lineNumber[0]], array_reverse($temp));
 
           // Get lines after the line number
           for ($count = 0, $i = 1; $count < self::TEX_GET_LINES && $i < self::TEX_MAX_LINES; $i++) {
@@ -153,29 +139,19 @@ protected function findErrors(array $errorOutput, $texLocation = NULL)
               break;
             }
           }
-
-          $this->filteredTexSource[] = "---";
-
+          $this->filteredTexSource[] = '---';
         }
       }
     }
   }
 
-  /**
-   * @return string
-   */
-  public function getFilteredTexSource()
+  public function getFilteredTexSource(): string
   {
     return implode("\n", $this->filteredTexSource);
   }
 
-  /**
-   * @return string
-   */
-  public function getFilteredLogSource()
+  public function getFilteredLogSource(): string
   {
     return implode("\n", $this->filteredLogSource);
   }
-
-
 } 
diff --git a/src/Form/Type/LatexType.php b/src/Form/Type/LatexType.php
index 105b214..a77e45b 100644
--- a/src/Form/Type/LatexType.php
+++ b/src/Form/Type/LatexType.php
@@ -8,7 +8,6 @@
 use Symfony\Component\OptionsResolver\OptionsResolver;
 
 /**
- * Class LatexType
  * You will want to use this type when using the html->latex conversion
  *
  * @author BobV
@@ -18,42 +17,40 @@ class LatexType extends AbstractType
 
   /**
    * Returns the default config used so you can use it as base for your own config
-   *
-   * @return array
    */
-  public static function getDefaultConfig()
+  public static function getDefaultConfig(): array
   {
-    return array(
-        'config' => array(
+    return [
+        'config' => [
             'entities'         => false,
             'basicEntities'    => false,
             'entities_greek'   => false,
             'entities_latin'   => false,
-            'toolbar'          => array(
-                array(
+            'toolbar'          => [
+                [
                     'name'   => 'basicstyles',
-                    'groups' => array('basicstyles', 'cleanup'),
-                    'items'  => array('Bold', 'Italic', 'Underline', 'Subscript', 'Superscript', '-', 'RemoveFormat'),
-                ),
-                array(
+                    'groups' => ['basicstyles', 'cleanup'],
+                    'items'  => ['Bold', 'Italic', 'Underline', 'Subscript', 'Superscript', '-', 'RemoveFormat'],
+                ],
+                [
                     'name'   => 'paragraph',
-                    'groups' => array('list', 'indent', 'blocks', 'align'),
-                    'items'  => array('NumberedList', 'BulletedList'
+                    'groups' => ['list', 'indent', 'blocks', 'align'],
+                    'items'  => ['NumberedList', 'BulletedList'
                       /**
                        * @todo Add support for the floats
                        * , '-', 'JustifyLeft', 'JustifyCenter', 'JustifyRight', 'JustifyBlock'
                        */
-                    ),
-                ),
-                array(
+                    ],
+                ],
+                [
                     'name'  => 'links',
-                    'items' => array('Link', 'Unlink'),
-                ),
-                array(
+                    'items' => ['Link', 'Unlink'],
+                ],
+                [
                     'name'   => 'clipboard',
-                    'groups' => array('clipboard', 'undo'),
-                    'items'  => array('Cut', 'Copy', 'Paste', 'PasteText', 'PasteFromWord', '-', 'Undo', 'Redo'),
-                ),
+                    'groups' => ['clipboard', 'undo'],
+                    'items'  => ['Cut', 'Copy', 'Paste', 'PasteText', 'PasteFromWord', '-', 'Undo', 'Redo'],
+                ],
                 /**
                  * @todo: add support for tables/special chars
                  * array(
@@ -61,50 +58,40 @@ public static function getDefaultConfig()
                  * 'items' => array('Table', 'SpecialChar'),
                  * ),
                  */
-                array(
+                [
                     'name'   => 'document',
-                    'groups' => array('mode', 'document', 'doctools'),
-                    'items'  => array('Source'),
-                ),
-                array(
+                    'groups' => ['mode', 'document', 'doctools'],
+                    'items'  => ['Source'],
+                ],
+                [
                     'name'  => 'tools',
-                    'items' => array('Maximize'),
-                ),
-            ),
+                    'items' => ['Maximize'],
+                ],
+            ],
             'extraPlugins'     => '',
             'removeDialogTabs' => 'link:upload;image:Upload;image:advanced;link:advanced',
-        )
-    );
+        ]
+    ];
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function buildView(FormView $view, FormInterface $form, array $options)
+  public function buildView(FormView $view, FormInterface $form, array $options): void
   {
-    if (!is_array($view->vars['attr'])) $view->vars['attr'] = array();
-    $view->vars['attr']['data-bobv-latex'] = NULL;
+    if (!is_array($view->vars['attr'])) {
+      $view->vars['attr'] = [];
+    }
+    $view->vars['attr']['data-bobv-latex'] = null;
   }
 
-  /**
-   * {@inheritdoc}
-   */
   public function getName(): string
   {
     return $this->getBlockPrefix();
   }
 
-  /**
-   * {@inheritdoc}
-   */
   public function getBlockPrefix() : string
   {
     return 'bobv_latex';
   }
 
-  /**
-   * {@inheritdoc}
-   */
   public function getParent(): ?string
   {
     $ivory_form_class = 'Ivory\CKEditorBundle\Form\Type\CKEditorType';
@@ -114,10 +101,7 @@ public function getParent(): ?string
     return method_exists('Symfony\Component\Form\AbstractType', 'getBlockPrefix') ? $form_class : 'ckeditor';
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function configureOptions(OptionsResolver $resolver)
+  public function configureOptions(OptionsResolver $resolver): void
   {
     $resolver->setDefaults(self::getDefaultConfig());
   }
diff --git a/src/Generator/LatexGenerator.php b/src/Generator/LatexGenerator.php
index 8ce4bdc..7b3d0f9 100644
--- a/src/Generator/LatexGenerator.php
+++ b/src/Generator/LatexGenerator.php
@@ -8,6 +8,7 @@
 use Bobv\LatexBundle\Exception\LatexParseException;
 use Bobv\LatexBundle\Latex\LatexBaseInterface;
 use DateTime;
+use DateTimeInterface;
 use Exception;
 use Symfony\Component\Filesystem\Exception\IOException;
 use Symfony\Component\Filesystem\Filesystem;
@@ -21,75 +22,37 @@
 use Twig\Error\RuntimeError;
 use Twig\Error\SyntaxError;
 
-/**
- * Class LatexGenerator
- */
 class LatexGenerator implements LatexGeneratorInterface
 {
-
-  /** @var string */
-  protected $cacheDir;
-  /** @var string */
-  protected $env;
-  /** @var Filesystem */
-  protected $filesystem;
-  /** @var bool */
-  protected $forceRegenerate;
-  /** @var LatexBaseInterface */
-  protected $latex;
-  /** @var DateTime */
-  protected $maxAge;
-  /** @var string */
-  protected $pdfLatexBinaryLocation;
-  /** @var string */
-  protected $bibliographyBinaryLocation;
-  /** @var string */
-  protected $outputDir;
-  /** @var int|float|null */
-  protected $timeout;
-  /** @var Environment */
-  protected $twig;
-
-  /**
-   * @param string      $cacheDir
-   * @param string      $env
-   * @param Environment $twig
-   * @param DateTime    $maxAge
-   * @param string      $pdfLatexBinaryLocation
-   * @param string      $bibliographyBinaryLocation
-   */
-  public function __construct($cacheDir, $env, $twig, $maxAge, $pdfLatexBinaryLocation, $bibliographyBinaryLocation) {
-    $this->cacheDir   = $cacheDir;
-    $this->env        = $env;
-    $this->twig       = $twig;
+  protected Filesystem $filesystem;
+  protected bool $forceRegenerate = false;
+  protected ?LatexBaseInterface $latex = null;
+  protected ?string $outputDir = null;
+  protected int|float|null $timeout = 60; // Default timeout from the Symfony Process component
+  protected DateTimeInterface $maxAge;
+
+  public function __construct(
+      protected string $cacheDir,
+      protected readonly string $env,
+      protected readonly Environment $twig,
+      string $maxAge,
+      protected readonly string $pdfLatexBinaryLocation,
+      protected readonly string $bibliographyBinaryLocation) {
     $this->filesystem = new Filesystem();
     $this->maxAge     = new DateTime();
     $this->maxAge->modify($maxAge);
-
-    $this->pdfLatexBinaryLocation     = $pdfLatexBinaryLocation;
-    $this->bibliographyBinaryLocation = $bibliographyBinaryLocation;
-
-    $this->forceRegenerate = false;
-
-    // Default timeout from the Symfony Process component
-    $this->timeout = 60;
   }
 
   /**
    * Generate a response containing a PDF document
    *
-   * @param LatexBaseInterface $latex
-   * @param bool               $download
-   *
-   * @return BinaryFileResponse
-   *
    * @throws ImageNotFoundException
    * @throws LatexException
    * @throws LoaderError
    * @throws RuntimeError
    * @throws SyntaxError
    */
-  public function createPdfResponse(LatexBaseInterface $latex, bool $download = true) {
+  public function createPdfResponse(LatexBaseInterface $latex, bool $download = true): BinaryFileResponse {
     $pdfLocation = $this->generate($latex);
 
     $response = new BinaryFileResponse($pdfLocation);
@@ -103,17 +66,13 @@ public function createPdfResponse(LatexBaseInterface $latex, bool $download = tr
   /**
    * Generate a response containing a generated .tex file
    *
-   * @param LatexBaseInterface $latex
-   * @param bool               $download
-   *
-   * @return BinaryFileResponse
    * @throws ImageNotFoundException
    * @throws LatexException
    * @throws LoaderError
    * @throws RuntimeError
    * @throws SyntaxError
    */
-  public function createTexResponse(LatexBaseInterface $latex, bool $download = true) {
+  public function createTexResponse(LatexBaseInterface $latex, bool $download = true): BinaryFileResponse {
     $texLocation = $this->generateLatex($latex);
 
     $response = new BinaryFileResponse($texLocation);
@@ -127,8 +86,6 @@ public function createTexResponse(LatexBaseInterface $latex, bool $download = tr
   /**
    * Compile a LaTeX object into the wanted PDF file
    *
-   * @param LatexBaseInterface $latex
-   *
    * @return string Location of the PDF document
    *
    * @throws ImageNotFoundException
@@ -137,7 +94,7 @@ public function createTexResponse(LatexBaseInterface $latex, bool $download = tr
    * @throws RuntimeError
    * @throws SyntaxError
    */
-  public function generate(LatexBaseInterface $latex) {
+  public function generate(LatexBaseInterface $latex): string {
     $this->latex = $latex;
     $texLocation = $this->generateLatex();
 
@@ -147,8 +104,6 @@ public function generate(LatexBaseInterface $latex) {
   /**
    * Generates a latex file for the given LaTeX object
    *
-   * @param LatexBaseInterface $latex
-   *
    * @return string Location of the generated LaTeX file
    *
    * @throws ImageNotFoundException
@@ -157,7 +112,7 @@ public function generate(LatexBaseInterface $latex) {
    * @throws RuntimeError
    * @throws SyntaxError
    */
-  public function generateLatex(LatexBaseInterface $latex = NULL) {
+  public function generateLatex(LatexBaseInterface $latex = NULL): string {
 
     if ($this->latex === NULL && $latex === NULL) {
       throw new LatexException("No latex file given");
@@ -175,7 +130,7 @@ public function generateLatex(LatexBaseInterface $latex = NULL) {
 
     // Check if there are undefined images
     $matches = array();
-    preg_match_all('/\\\\includegraphics(\[.+\])?\{([^}]+)\}/u', $texData, $matches);
+    preg_match_all('/\\\\includegraphics(\[.+])?\{([^}]+)}/u', $texData, $matches);
     foreach ($matches[2] as $imageLocation) {
       if (!$this->filesystem->exists($imageLocation)) {
         throw new ImageNotFoundException($imageLocation);
@@ -217,7 +172,7 @@ public function generateLatex(LatexBaseInterface $latex = NULL) {
    * @throws IOException
    * @throws LatexException
    */
-  public function generatePdf($texLocation, array $compileOptions = array()) {
+  public function generatePdf(string $texLocation, array $compileOptions = []): string {
 
     // Check if the compiled tex file exists
     if (!$this->filesystem->exists($texLocation)) {
@@ -242,34 +197,19 @@ public function generatePdf($texLocation, array $compileOptions = array()) {
 
   }
 
-  /**
-   * @param $cacheDir
-   *
-   * @return $this
-   */
-  public function setCacheDir($cacheDir) {
+  public function setCacheDir(string $cacheDir): self {
     $this->cacheDir = $cacheDir;
 
     return $this;
   }
 
-  /**
-   * @param boolean $forceRegenerate
-   *
-   * @return LatexGenerator
-   */
-  public function setForceRegenerate($forceRegenerate) {
+  public function setForceRegenerate(bool $forceRegenerate): self {
     $this->forceRegenerate = $forceRegenerate;
 
     return $this;
   }
 
-  /**
-   * @param DateTime $maxAge
-   *
-   * @return LatexGenerator
-   */
-  public function setMaxAge($maxAge) {
+  public function setMaxAge(DateTimeInterface $maxAge): self {
     $this->maxAge = $maxAge;
 
     return $this;
@@ -280,10 +220,8 @@ public function setMaxAge($maxAge) {
    * To disable the timeout, set this value to null.
    *
    * @param int|float|null $timeout The timeout in seconds
-   *
-   * @return LatexGenerator
    */
-  public function setTimeout($timeout) {
+  public function setTimeout(int|float|null $timeout): self {
     $this->timeout = $timeout;
 
     return $this;
@@ -294,7 +232,7 @@ public function setTimeout($timeout) {
    *
    * @throws IOException
    */
-  protected function checkFilesystem() {
+  protected function checkFilesystem(): void {
     // Check if the cache dir exists
     if (!$this->filesystem->exists($this->getCacheBasePath())) {
       try {
@@ -312,10 +250,9 @@ protected function checkFilesystem() {
    * @param string $texLocation    Location of the .tex file
    * @param array  $compileOptions Optional compile options for pdflatex
    *
-   * @return string
    * @throws Exception
    */
-  protected function compilePdf($texLocation, array $compileOptions = array()) {
+  protected function compilePdf(string $texLocation, array $compileOptions = []): string {
     $pdfLocation = explode('.tex', $texLocation)[0] . '.pdf';
 
     // Do not regenerate unless cache is off (dev mode or force regenerate or passed maxAge)
@@ -399,23 +336,17 @@ protected function compilePdf($texLocation, array $compileOptions = array()) {
     return $pdfLocation;
   }
 
-  /**
-   * Returns the cache path
-   */
-  protected function getCacheBasePath() {
+  protected function getCacheBasePath(): string {
     return $this->cacheDir . '/BobvLatex/';
   }
 
   /**
    * Write the file to the cache directory
    *
-   * @param string $texData
-   * @param        $fileName
-   *
    * @return string The location of the saved .tex file
    * @throws IOException
    */
-  protected function writeTexFile($texData, $fileName) {
+  protected function writeTexFile(string $texData, string $fileName): string {
     $this->checkFilesystem();
     $this->outputDir = $this->getCacheBasePath() . hash('ripemd160', $texData) . '/';
     $texLocation     = $this->outputDir . $fileName . '.tex';
@@ -443,28 +374,13 @@ protected function writeTexFile($texData, $fileName) {
 
   /**
    * Check if the line contains a reference error
-   *
-   * @param $value
-   *
-   * @return bool
    */
-  private function findReferenceError($value) {
+  private function findReferenceError(string $value): bool {
     return preg_match_all('/reference|change/ui', $value) > 0;
   }
 
-  /**
-   * Run a latex process
-   *
-   * @param string $commandLine
-   *
-   * @return Process
-   */
-  private function runProcess(string $commandLine) {
-    if (method_exists(Process::class, 'fromShellCommandline')) {
-      $process = Process::fromShellCommandline($commandLine);
-    } else {
-      $process = new Process($commandLine);
-    }
+  private function runProcess(string $commandLine): Process {
+    $process = Process::fromShellCommandline($commandLine);
 
     $process->setTimeout($this->timeout);
     $process->run();
diff --git a/src/Generator/LatexGeneratorInterface.php b/src/Generator/LatexGeneratorInterface.php
index a0f28ab..eda1114 100644
--- a/src/Generator/LatexGeneratorInterface.php
+++ b/src/Generator/LatexGeneratorInterface.php
@@ -3,6 +3,7 @@
 namespace Bobv\LatexBundle\Generator;
 
 use Bobv\LatexBundle\Latex\LatexBaseInterface;
+use DateTimeInterface;
 use Symfony\Component\HttpFoundation\BinaryFileResponse;
 
 interface LatexGeneratorInterface
@@ -11,42 +12,32 @@ interface LatexGeneratorInterface
   /**
    * Generate a response containing a PDF document
    *
-   * @param LatexBaseInterface $latex
    * @param bool               $download If set to false, the attachment value will be omitted from the
    *                                     Content-Disposition field. Defaults to true.
-   *
-   * @return BinaryFileResponse
    */
-  public function createPdfResponse(LatexBaseInterface $latex, bool $download = true);
+  public function createPdfResponse(LatexBaseInterface $latex, bool $download = true): BinaryFileResponse;
 
   /**
    * Generate a response containing a generated .tex file
    *
-   * @param LatexBaseInterface $latex
    * @param bool               $download If set to false, the attachment value will be omitted from the
    *                                     Content-Disposition field. Defaults to true.
-   *
-   * @return BinaryFileResponse
    */
-  public function createTexResponse(LatexBaseInterface $latex, bool $download = true);
+  public function createTexResponse(LatexBaseInterface $latex, bool $download = true): BinaryFileResponse;
 
   /**
    * Compile a LaTeX object into the wanted PDF file
    *
-   * @param \Bobv\LatexBundle\Latex\LatexBaseInterface $latex
-   *
    * @return string Location of the PDF document
    */
-  public function generate(LatexBaseInterface $latex);
+  public function generate(LatexBaseInterface $latex): string;
 
   /**
    * Generates a latex file for the given LaTeX object
    *
-   * @param \Bobv\LatexBundle\Latex\LatexBaseInterface $latex
-   *
    * @return string Location of the generated LaTeX file
    */
-  public function generateLatex(LatexBaseInterface $latex = NULL);
+  public function generateLatex(LatexBaseInterface $latex = null): string;
 
   /**
    * Generates a PDF from a given LaTeX location
@@ -56,36 +47,19 @@ public function generateLatex(LatexBaseInterface $latex = NULL);
    *
    * @return string Location of the generated PDF file
    */
-  public function generatePdf($texLocation, array $compileOptions = array());
+  public function generatePdf(string $texLocation, array $compileOptions = []): string;
 
-  /**
-   * @param $cacheDir
-   *
-   * @return LatexGeneratorInterface
-   */
-  public function setCacheDir($cacheDir);
+  public function setCacheDir(string $cacheDir): self;
 
-  /**
-   * @param boolean $forceRegenerate
-   *
-   * @return LatexGeneratorInterface
-   */
-  public function setForceRegenerate($forceRegenerate);
+  public function setForceRegenerate(bool $forceRegenerate): self;
 
-  /**
-   * @param \DateTime $maxAge
-   *
-   * @return LatexGeneratorInterface
-   */
-  public function setMaxAge($maxAge);
+  public function setMaxAge(DateTimeInterface $maxAge): self;
 
   /**
    * Sets the process timeout (max. runtime).
    * To disable the timeout, set this value to null.
    *
    * @param int|float|null $timeout The timeout in seconds
-   *
-   * @return LatexGeneratorInterface
    */
-  public function setTimeout($timeout);
+  public function setTimeout(int|float|null $timeout): self;
 }
diff --git a/src/Generator/LockedLatexGenerator.php b/src/Generator/LockedLatexGenerator.php
index ec5384e..6098aa1 100644
--- a/src/Generator/LockedLatexGenerator.php
+++ b/src/Generator/LockedLatexGenerator.php
@@ -4,41 +4,27 @@
 
 use Bobv\LatexBundle\Exception\LatexNotLockedException;
 use Bobv\LatexBundle\Latex\LatexBaseInterface;
+use DateTimeInterface;
 use LogicException;
+use Symfony\Component\HttpFoundation\BinaryFileResponse;
 use Symfony\Component\Lock\Lock;
 use Symfony\Component\Lock\LockFactory;
 use Symfony\Component\Lock\Store\FlockStore;
 
 /**
- * Class LockedLatexGenerator
- *
  * Lock LaTeX pdf generation to prevent the same files being rendered at the same time.
  */
 class LockedLatexGenerator implements LatexGeneratorInterface, LockedLatexGeneratorInterface
 {
-  /**
-   * @var LatexGeneratorInterface
-   */
-  private $generator;
-  /**
-   * @var LockFactory
-   */
-  private $lockFactory;
-  /**
-   * @var Lock|null
-   */
-  private $lock;
-  /**
-   * @var int
-   */
-  private $timeout;
+  private LockFactory $lockFactory; // Set in constructor
+  private ?Lock $lock = null;
+  private float|int|null $timeout; // Set in constructor
 
-  public function __construct(LatexGeneratorInterface $generator) {
+  public function __construct(private readonly LatexGeneratorInterface $generator) {
     if (!class_exists(LockFactory::class)) {
       throw new LogicException('In order to use the LockedLatexGenerator, try running "composer require symfony/lock".');
     }
 
-    $this->generator = $generator;
     $this->setTimeout(60);
     $this->lockFactory = new LockFactory(new FlockStore());
   }
@@ -65,82 +51,55 @@ public function releaseLock(): LatexGeneratorInterface {
     return $this;
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function createPdfResponse(LatexBaseInterface $latex, bool $download = true) {
+  public function createPdfResponse(LatexBaseInterface $latex, bool $download = true): BinaryFileResponse {
     $this->ensureLock();
 
     return $this->generator->createPdfResponse($latex, $download);
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function createTexResponse(LatexBaseInterface $latex, bool $download = true) {
+  public function createTexResponse(LatexBaseInterface $latex, bool $download = true): BinaryFileResponse {
     $this->ensureLock();
 
     return $this->generator->createTexResponse($latex, $download);
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function generate(LatexBaseInterface $latex) {
+  public function generate(LatexBaseInterface $latex): string {
     $this->ensureLock();
 
     return $this->generator->generate($latex);
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function generateLatex(LatexBaseInterface $latex = NULL) {
+  public function generateLatex(LatexBaseInterface $latex = null): string {
     $this->ensureLock();
 
     return $this->generator->generateLatex($latex);
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function generatePdf($texLocation, array $compileOptions = array()) {
+  public function generatePdf($texLocation, array $compileOptions = []): string {
     $this->ensureLock();
 
     return $this->generator->generatePdf($texLocation, $compileOptions);
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function setCacheDir($cacheDir) {
+  public function setCacheDir(string $cacheDir): self {
     $this->generator->setCacheDir($cacheDir);
 
     return $this;
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function setForceRegenerate($forceRegenerate) {
+  public function setForceRegenerate(bool $forceRegenerate): self {
     $this->generator->setForceRegenerate($forceRegenerate);
 
     return $this;
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function setMaxAge($maxAge) {
+  public function setMaxAge(DateTimeInterface $maxAge): self {
     $this->generator->setMaxAge($maxAge);
 
     return $this;
   }
 
-  /**
-   * @inheritDoc
-   */
-  public function setTimeout($timeout) {
+  public function setTimeout(float|int|null $timeout): self {
     $this->generator->setTimeout($timeout);
 
     // Save timeout for lock, include some trivial overhead margin, and refresh when required
@@ -155,7 +114,7 @@ public function setTimeout($timeout) {
   /**
    * Verify the callee has already exclusive access
    */
-  private function ensureLock() {
+  private function ensureLock(): void {
     if (!$this->lock->isAcquired()) {
       throw new LatexNotLockedException();
     }
diff --git a/src/Generator/LockedLatexGeneratorInterface.php b/src/Generator/LockedLatexGeneratorInterface.php
index 5a21047..f6077d7 100644
--- a/src/Generator/LockedLatexGeneratorInterface.php
+++ b/src/Generator/LockedLatexGeneratorInterface.php
@@ -3,8 +3,6 @@
 namespace Bobv\LatexBundle\Generator;
 
 /**
- * Class LockedLatexGenerator
- *
  * Lock LaTeX pdf generation to prevent the same files being rendered at the same time.
  */
 interface LockedLatexGeneratorInterface extends LatexGeneratorInterface
diff --git a/src/Helper/Parser.php b/src/Helper/Parser.php
index 8f4334d..30b94d8 100644
--- a/src/Helper/Parser.php
+++ b/src/Helper/Parser.php
@@ -3,25 +3,17 @@
 namespace Bobv\LatexBundle\Helper;
 
 /**
- * Class Parser
  * @author BobV
  */
 class Parser
 {
-
-  /**
-   * @var array
-   */
-  private $htmlCodes;
+  private array $htmlCodes; // Set in constructor
 
   /**
    * @var string[]
    */
-  private $greekMap;
+  private array $greekMap;
 
-  /**
-   * Parser constructor.
-   */
   public function __construct() {
     $this->htmlCodes = array_flip(get_html_translation_table(HTML_ENTITIES, ENT_QUOTES | ENT_HTML5));
 
@@ -75,15 +67,13 @@ public function __construct() {
   /**
    * Parse the text and replace known special latex characters correctly
    *
-   * @param string  $text          The string that needs to be parsed
-   * @param boolean $checkTable    If set, tables should be detected automatically (default true)
-   * @param boolean $removeLatex   If set, all LaTeX commands will be removed (default false)
-   * @param boolean $parseNewLines If set, newline characters will be replaced by LaTeX entities (default false)
-   * @param bool    $removeGreek   If set, any greek character will be replace by their LaTeX math equivalent (default false)
-   *
-   * @return mixed
+   * @param string|null $text          The string that needs to be parsed
+   * @param boolean     $checkTable    If set, tables should be detected automatically (default true)
+   * @param boolean     $removeLatex   If set, all LaTeX commands will be removed (default false)
+   * @param boolean     $parseNewLines If set, newline characters will be replaced by LaTeX entities (default false)
+   * @param bool        $removeGreek   If set, any greek character will be replaced by their LaTeX math equivalent (default false)
    */
-  public function parseText($text, $checkTable = true, $removeLatex = false, $parseNewLines = false, $removeGreek = false) {
+  public function parseText(?string $text, bool $checkTable = true, bool $removeLatex = false, bool $parseNewLines = false, bool $removeGreek = false): string {
 
     // Try to replace HTML entities
     preg_match_all('/&[a-zA-Z]+;/iu', $text, $matches);
@@ -236,12 +226,8 @@ public function parseText($text, $checkTable = true, $removeLatex = false, $pars
 
   /**
    * Parse the html input and create latex code of it
-   *
-   * @param $text
-   *
-   * @return mixed
    */
-  public static function parseHtml($text) {
+  public static function parseHtml(?string $text): ?string {
 
     // Replace NO-BREAK-SPACE with normal space
     $text = str_replace("\xc2\xa0", ' ', $text);
@@ -272,25 +258,20 @@ public static function parseHtml($text) {
     $text = $DOM->saveHTML();
 
     // Replace junk from URL to get it readable
-    $text = preg_replace("/(mailto:|https?:\/\/)?(([\da-z\.-]+)(\.|@)([a-z\.]{2,6})([\/\w\.-]*[\/\w-])*\/?)/smui", '$2', $text);
+    $text = preg_replace("/(mailto:|https?:\/\/)?(([\da-z.-]+)([.@])([a-z.]{2,6})([\/\w.-]*[\/\w-])*\/?)/smui", '$2', $text);
 
     return strip_tags($text);
   }
 
   /**
    * Encapsulate the content of all given tags in the given document with the replacement
-   *
-   * @param \DOMDocument $document
-   * @param string       $tag
-   * @param string       $replacementStart
-   * @param string       $replacementEnd
    */
-  private static function updateNode(\DOMDocument &$document, $tag, $replacementStart, $replacementEnd = '}') {
+  private static function updateNode(\DOMDocument &$document, string $tag, string $replacementStart, string $replacementEnd = '}'): void {
     $elements = $document->getElementsByTagName($tag);
     /** @var \DOMElement $element */
     foreach ($elements as $element) {
 
-      // Check if a attribute from the tag is needed for the replacement start
+      // Check if an attribute from the tag is needed for the replacement start
       $replacementStartNode = $document->createTextNode($replacementStart);
 
       // Create the replacement end node
diff --git a/src/Helper/Sanitize.php b/src/Helper/Sanitize.php
index 213654b..e93d3b8 100644
--- a/src/Helper/Sanitize.php
+++ b/src/Helper/Sanitize.php
@@ -2,7 +2,6 @@
 namespace Bobv\LatexBundle\Helper;
 
 /**
- * Class Sanitizer
  * @author BobV
  */
 class Sanitize
@@ -15,10 +14,10 @@ class Sanitize
    *
    * @return string
    */
-  public static function sanitizeText($text) {
-    $strip = array("~", "`", "!", "@", "#", "$", "%", "^", "&", "*", "(", ")", "_", "=", "+", "[", "{", "]",
+  public static function sanitizeText(string $text): string {
+    $strip = ["~", "`", "!", "@", "#", "$", "%", "^", "&", "*", "(", ")", "_", "=", "+", "[", "{", "]",
         "}", "\\", "|", ";", ":", "\"", "'", "&#8216;", "&#8217;", "&#8220;", "&#8221;", "&#8211;", "&#8212;",
-        "—", "–", ",", "<", ".", ">", "/", "?");
+        "—", "–", ",", "<", ".", ">", "/", "?"];
 
     $text = trim(str_replace($strip, "", strip_tags($text)));
 
diff --git a/src/Latex/Base/Article.php b/src/Latex/Base/Article.php
index 8cd5dbe..4a4c7e3 100644
--- a/src/Latex/Base/Article.php
+++ b/src/Latex/Base/Article.php
@@ -3,7 +3,6 @@
 namespace Bobv\LatexBundle\Latex\Base;
 
 /**
- * Class LatexArticle
  * Base article
  *
  * @author BobV
@@ -13,10 +12,8 @@ class Article extends Base
 
   /**
    * Article constructor, sets defaults
-   *
-   * @param string $filename
    */
-  public function __construct($filename)
+  public function __construct(string $filename)
   {
     // Define standard values
     $this->template = '@BobvLatex/Base/article.tex.twig';
diff --git a/src/Latex/Base/Base.php b/src/Latex/Base/Base.php
index 2c19147..bd3f0ec 100644
--- a/src/Latex/Base/Base.php
+++ b/src/Latex/Base/Base.php
@@ -5,8 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexBase;
 
 /**
- * Class Base
- *
  * @internal Note that this class does not define a template!
  *           It currently is only used by Article and Book as base to avoid code duplication
  *
@@ -14,17 +12,11 @@
  */
 abstract class Base extends LatexBase
 {
-
-  /**
-   * Book constructor, sets defaults
-   *
-   * @param string $filename
-   */
-  public function __construct($filename)
+  public function __construct(string $filename)
   {
     // Define standard values
     $dateTime       = new \DateTime();
-    $this->params   = array(
+    $this->params   = [
         'options'        => null,
 
         'lhead'          => '', // Top left header
@@ -55,9 +47,9 @@ public function __construct($filename)
 
         'tocdepth'       => '2', // TOC depth
 
-        'extra_commands' => array(), // Define extra commands if needed
-        'packages'       => array(), // Define extra packages to use
-    );
+        'extra_commands' => [], // Define extra commands if needed
+        'packages'       => [], // Define extra packages to use
+    ];
 
     // Use the ulem package
     $this->addPackage('ulem');
@@ -65,5 +57,4 @@ public function __construct($filename)
     // Call parent constructor
     parent::__construct($filename);
   }
-
 }
diff --git a/src/Latex/Base/Book.php b/src/Latex/Base/Book.php
index 82175e7..2dee113 100644
--- a/src/Latex/Base/Book.php
+++ b/src/Latex/Base/Book.php
@@ -3,7 +3,6 @@
 namespace Bobv\LatexBundle\Latex\Base;
 
 /**
- * Class LatexBook
  * Base Book
  *
  * @author BobV
@@ -13,10 +12,8 @@ class Book extends Base
 
   /**
    * Book constructor, sets defaults
-   *
-   * @param string $filename
    */
-  public function __construct($filename)
+  public function __construct(string $filename)
   {
     // Define standard values
     $this->template = '@BobvLatex/Base/book.tex.twig';
diff --git a/src/Latex/Base/Letter.php b/src/Latex/Base/Letter.php
index a14f6ae..676c96d 100644
--- a/src/Latex/Base/Letter.php
+++ b/src/Latex/Base/Letter.php
@@ -5,7 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexBase;
 
 /**
- * Class LatexLetter
  * Base letter
  *
  * @author BobV
@@ -15,15 +14,13 @@ class Letter extends LatexBase
 
   /**
    * Letter constructor, sets defaults
-   *
-   * @param string $filename
    */
-  public function __construct($filename)
+  public function __construct(string $filename)
   {
     // Define standard values
     $this->template = '@BobvLatex/Base/letter.tex.twig';
     $datetime = new \DateTime();
-    $this->params   = array(
+    $this->params   = [
         'pagenumber'     => 'false',     // Whether to print pagenumbers from page 2 and forward
         'parskip'        => 'full',      // Spacing between paragraphs (full, half, ..)
         'fromalign'      => 'right',     // Alignment of the from address
@@ -44,9 +41,9 @@ public function __construct($filename)
 
         'date'           => $datetime->format('d-m-Y'),
 
-        'extra_commands' => array(), // Define extra commands if needed
-        'packages'       => array(), // Define extra packages to use
-    );
+        'extra_commands' => [], // Define extra commands if needed
+        'packages'       => [], // Define extra packages to use
+    ];
 
     // Use the ulem package
     $this->addPackage('ulem');
diff --git a/src/Latex/Base/Standalone.php b/src/Latex/Base/Standalone.php
index fc4c390..00ea67f 100644
--- a/src/Latex/Base/Standalone.php
+++ b/src/Latex/Base/Standalone.php
@@ -8,19 +8,17 @@ class Standalone extends LatexBase
 {
   /**
    * Standalone constructor, sets defaults
-   *
-   * @param string $filename
    */
-  public function __construct($filename) {
+  public function __construct(string $filename) {
     // Define standard values
     $this->template = '@BobvLatex/Base/standalone.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'mode'           => 'crop',  // Define the standalone mode
         'border'         => '1pt',   // Content border
         'varwidth'       => true,    // Variable width mode
-        'extra_commands' => array(), // Define extra commands if needed
-        'packages'       => array(), // Define extra packages to use
-    );
+        'extra_commands' => [],      // Define extra commands if needed
+        'packages'       => [],      // Define extra packages to use
+    ];
 
     // Call parent constructor
     parent::__construct($filename);
diff --git a/src/Latex/Element/BlackTitle.php b/src/Latex/Element/BlackTitle.php
index f02fc2c..735f161 100644
--- a/src/Latex/Element/BlackTitle.php
+++ b/src/Latex/Element/BlackTitle.php
@@ -4,23 +4,16 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class BlackTitle
- *
  * @author BobV
  */
 class BlackTitle extends LatexElement
 {
-
-  /**
-   * @param $title
-   */
-  public function __construct($title)
+  public function __construct(string $title)
   {
     $this->template = '@BobvLatex/Element/blacktitle.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'title'          => $title,
-        'extra_commands' => array(),
-    );
+        'extra_commands' => [],
+    ];
   }
-
 }
diff --git a/src/Latex/Element/CustomCommand.php b/src/Latex/Element/CustomCommand.php
index 7add029..64930d7 100644
--- a/src/Latex/Element/CustomCommand.php
+++ b/src/Latex/Element/CustomCommand.php
@@ -5,7 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class CustomCommand
  * Custom command
  *
  * @author BobV
@@ -15,16 +14,14 @@ class CustomCommand extends LatexElement
 
   /**
    * Constructor of the custom command, also defines the defaults
-   *
-   * @param string $text
    */
-  public function __construct($custom)
+  public function __construct(string $custom)
   {
     // Define defaults
     $this->template = '@BobvLatex/Element/custom_command.tex.twig';
-    $this->params   = array(
-        'custom'           => $custom,
-    );
+    $this->params   = [
+        'custom' => $custom,
+    ];
   }
 
 }
diff --git a/src/Latex/Element/CustomElement.php b/src/Latex/Element/CustomElement.php
index 748418a..81f2627 100644
--- a/src/Latex/Element/CustomElement.php
+++ b/src/Latex/Element/CustomElement.php
@@ -5,7 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class CustomElement
  * Custom element
  *
  * @author BobV
@@ -15,16 +14,14 @@ class CustomElement extends LatexElement
 
   /**
    * Constructor of the custom element, also defines the defaults
-   *
-   * @param string $custom
    */
-  public function __construct($custom)
+  public function __construct(string $custom)
   {
     // Define defaults
     $this->template = '@BobvLatex/Element/custom_element.tex.twig';
-    $this->params   = array(
-        'custom'           => $custom,
-    );
+    $this->params   = [
+        'custom' => $custom,
+    ];
   }
 
 }
diff --git a/src/Latex/Element/EscapedText.php b/src/Latex/Element/EscapedText.php
index 2077842..d605bfc 100644
--- a/src/Latex/Element/EscapedText.php
+++ b/src/Latex/Element/EscapedText.php
@@ -5,7 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class EscapedText
  * Base text element (fully escaped)
  *
  * @author BobV
@@ -15,17 +14,15 @@ class EscapedText extends LatexElement
 
   /**
    * Constructor of the title element, also defines the defaults
-   *
-   * @param string $text
    */
-  public function __construct($text)
+  public function __construct(string $text)
   {
     // Define defaults
     $this->template = '@BobvLatex/Element/escaped_text.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'text'           => $text,
-        'extra_commands' => array(),
-    );
+        'extra_commands' => [],
+    ];
   }
 
 }
diff --git a/src/Latex/Element/Graphic.php b/src/Latex/Element/Graphic.php
index 6771ae5..fd7f001 100644
--- a/src/Latex/Element/Graphic.php
+++ b/src/Latex/Element/Graphic.php
@@ -5,7 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class Graphic
  * Base graphic element
  *
  * @author BobV
@@ -15,15 +14,12 @@ class Graphic extends LatexElement
 
   /**
    * Constructor of the graphic element, also defines the defaults
-   *
-   * @param string $graphic_location
-   * @param string $caption
    */
-  public function __construct($graphic_location, $caption = false)
+  public function __construct(string $graphic_location, string|bool $caption = false)
   {
     // Define defaults
     $this->template = '@BobvLatex/Element/graphic.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'placement'      => 'ht!',
         'centering'      => true,
         'location'       => $graphic_location,
@@ -31,8 +27,8 @@ public function __construct($graphic_location, $caption = false)
         'options'        => '',
         'caption'        => $caption,
         'label'          => 'fig:' . basename($graphic_location),
-        'extra_commands' => array(),
-    );
+        'extra_commands' => [],
+    ];
   }
 
 }
diff --git a/src/Latex/Element/IncludePdf.php b/src/Latex/Element/IncludePdf.php
index 44e65a5..281eb48 100644
--- a/src/Latex/Element/IncludePdf.php
+++ b/src/Latex/Element/IncludePdf.php
@@ -6,7 +6,6 @@
 use Symfony\Component\Process\Process;
 
 /**
- * Class IncludePdf
  * Include PDF
  *
  * @author BobV
@@ -16,24 +15,21 @@ class IncludePdf extends LatexElement
 
   /**
    * Constructor of the include pdf element, also defines the defaults
-   *
-   * @param string $fileLocation
-   * @param boolean $skipFirstWallpaper
    */
-  public function __construct($fileLocation, $skipFirstWallpaper = true)
+  public function __construct(string $fileLocation, bool $skipFirstWallpaper = true)
   {
     // Check amount of pages to avoid a newpage
-    if (!$skipFirstWallpaper){
+    if (!$skipFirstWallpaper) {
       $totalPages = $this->getPDFPages($fileLocation);
       $pages = '{2-}';
-    }else{
+    } else {
       $totalPages = 0;
       $pages = '{1-}';
     }
 
     // Define defaults
     $this->template = '@BobvLatex/Element/includepdf.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'totalPages'           => $totalPages,
         'skip_first_wallpaper' => $skipFirstWallpaper,
         'pages'                => $pages,
@@ -44,27 +40,19 @@ public function __construct($fileLocation, $skipFirstWallpaper = true)
         'y_offset'             => '0pt',
         'x_offset'             => '0pt',
         'wallpaper_scaling'    => '0.83'
-    );
+    ];
   }
 
   /**
    * Source: http://stackoverflow.com/questions/14644353/get-the-number-of-pages-in-a-pdf-document
-   *
-   * @param $document
-   *
-   * @return int
    */
-  private function getPDFPages($document)
+  private function getPDFPages(string $document): int
   {
     $commandLine     = sprintf('pdfinfo %s', $document);
-    if (method_exists(Process::class, 'fromShellCommandline')) {
-      $process = Process::fromShellCommandline($commandLine);
-    } else {
-      $process = new Process($commandLine);
-    }
+    $process = Process::fromShellCommandline($commandLine);
 
     $process->run();
-    if($process->getExitCode() !== 0){
+    if ($process->getExitCode() !== 0) {
       return 0;
     }
     $output = explode("\n", $process->getOutput());
diff --git a/src/Latex/Element/Letter.php b/src/Latex/Element/Letter.php
index 638e937..e36775a 100644
--- a/src/Latex/Element/Letter.php
+++ b/src/Latex/Element/Letter.php
@@ -5,7 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class Letter
  * Base letter element
  *
  * @author BobV
@@ -15,22 +14,18 @@ class Letter extends LatexElement
 
   /**
    * Constructor of the title element, also defines the defaults
-   *
-   * @param string $address
-   * @param string $opening
-   * @param string $text
    */
-  public function __construct($address, $opening, $text)
+  public function __construct(string $address, string $opening, string $text)
   {
     // Define defaults
     $this->template = '@BobvLatex/Element/letter.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'address'        => $address, // Address
         'opening'        => $opening, // Opening of the letter
         'text'           => $text,    // Content of the letter
 
-        'extra_commands' => array(),  // Define extra commands if needed
-    );
+        'extra_commands' => [],  // Define extra commands if needed
+    ];
   }
 
 }
diff --git a/src/Latex/Element/Listing.php b/src/Latex/Element/Listing.php
index 7822f8a..acb23d8 100644
--- a/src/Latex/Element/Listing.php
+++ b/src/Latex/Element/Listing.php
@@ -5,7 +5,6 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class Listing
  * Base list element
  *
  * @author BobV
@@ -15,18 +14,15 @@ class Listing extends LatexElement
 
   /**
    * Constructor of the listing element, also defines the defaults
-   *
-   * @param array $list
-   * @param bool  $enumerate If set, use enumerate instead of itemize
    */
   public function __construct(array $list, bool $enumerate = false) {
     // Define defaults
     $this->template = '@BobvLatex/Element/listing.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'list'           => $list,
-        'extra_commands' => array(),
+        'extra_commands' => [],
         'enumerate'      => $enumerate,
-    );
+    ];
   }
 
 }
diff --git a/src/Latex/Element/LongTable.php b/src/Latex/Element/LongTable.php
index 70b5e6c..8341d0f 100644
--- a/src/Latex/Element/LongTable.php
+++ b/src/Latex/Element/LongTable.php
@@ -5,34 +5,32 @@
 
 class LongTable extends LatexElement
 {
-
   /**
    * @param array $rows Alignment rows, for example array(l,r,c)
    */
-  public function __construct($rows = array())
+  public function __construct(array $rows = [])
   {
-
     // Define defaults
     $this->template = '@BobvLatex/Element/longtable.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'caption'        => NULL,
         'firsthead'      => NULL,
         'head'           => NULL,
         'foot'           => NULL,
         'lastfoot'       => NULL,
         'rows'           => $rows,
-        'data'           => array(),
-        'extra_commands' => array(),
-    );
+        'data'           => [],
+        'extra_commands' => [],
+    ];
   }
 
-  public function addRow($row)
+  public function addRow($row): self
   {
     $data   = $this->getParams()['data'];
-    $data[] = array(
+    $data[] = [
         'newRule' => true,
         'data'    => $row,
-    );
+    ];
     $this->setParam('data', $data);
 
     return $this;
diff --git a/src/Latex/Element/TOC.php b/src/Latex/Element/TOC.php
index 2eb66ec..4fe5de7 100644
--- a/src/Latex/Element/TOC.php
+++ b/src/Latex/Element/TOC.php
@@ -4,13 +4,10 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class TOC
- *
  * @author BobV
  */
 class TOC extends LatexElement
 {
-
   /**
    * Constructor of the TOC element, also defines the default
    */
diff --git a/src/Latex/Element/Table.php b/src/Latex/Element/Table.php
index 2665002..da961d9 100644
--- a/src/Latex/Element/Table.php
+++ b/src/Latex/Element/Table.php
@@ -5,40 +5,39 @@
 
 class Table extends LatexElement
 {
-
   /**
    * @param array $rows Alignment rows, for example array(l,r,c)
    */
-  public function __construct($rows = array())
+  public function __construct(array $rows = [])
   {
 
     // Define defaults
     $this->template = '@BobvLatex/Element/table.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'tabularx'       => true,
         'caption'        => null,
         'rows'           => $rows,
-        'data'           => array(),
+        'data'           => [],
         'width'          => '\textwidth',
-        'extra_commands' => array(),
-    );
+        'extra_commands' => [],
+    ];
   }
 
-  public function addBottomRule()
+  public function addBottomRule(): self
   {
     $this->addRule('\bottomrule');
 
     return $this;
   }
 
-  public function addMidRule()
+  public function addMidRule(): self
   {
     $this->addRule('\midrule');
 
     return $this;
   }
 
-  public function addRow($row)
+  public function addRow($row): self
   {
     $data = $this->getParams()['data'];
     $data[] = array(
@@ -50,14 +49,14 @@ public function addRow($row)
     return $this;
   }
 
-  public function addTopRule()
+  public function addTopRule(): self
   {
     $this->addRule('\toprule');
 
     return $this;
   }
 
-  private function addRule($rule)
+  private function addRule($rule): void
   {
     $data = $this->getParams()['data'];
     $data[] = array(
@@ -66,5 +65,4 @@ private function addRule($rule)
     );
     $this->setParam('data', $data);
   }
-
 }
diff --git a/src/Latex/Element/Text.php b/src/Latex/Element/Text.php
index a8586b1..e5f0e35 100644
--- a/src/Latex/Element/Text.php
+++ b/src/Latex/Element/Text.php
@@ -5,27 +5,22 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class Text
  * Base text element
  *
  * @author BobV
  */
 class Text extends LatexElement
 {
-
   /**
    * Constructor of the title element, also defines the defaults
-   *
-   * @param string $text
    */
-  public function __construct($text)
+  public function __construct(string $text)
   {
     // Define defaults
     $this->template = '@BobvLatex/Element/text.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'text'           => $text,
-        'extra_commands' => array(),
-    );
+        'extra_commands' => [],
+    ];
   }
-
 }
diff --git a/src/Latex/Element/TitlePage.php b/src/Latex/Element/TitlePage.php
index d54c1e6..e18475a 100644
--- a/src/Latex/Element/TitlePage.php
+++ b/src/Latex/Element/TitlePage.php
@@ -5,27 +5,20 @@
 use Bobv\LatexBundle\Latex\LatexElement;
 
 /**
- * Class TitlePage
  * Base title page element
  *
  * @author BobV
  */
 class TitlePage extends LatexElement
 {
-
   /**
    * Constructor of the title page element, also defines the defaults
-   *
-   * @param string $title
-   * @param string $subtitle
-   * @param string $author
-   * @param string $date
    */
-  public function __construct($title, $subtitle='', $author='', $date = '')
+  public function __construct(string $title, string $subtitle = '', string $author = '', string $date = '')
   {
     // Define defaults
     $this->template = '@BobvLatex/Element/titlepage.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'title'           => $title,
         'subtitle'        => $subtitle,
         'author'          => $author,
@@ -34,9 +27,7 @@ public function __construct($title, $subtitle='', $author='', $date = '')
         'vspace'          => '2in',
         'vspace_subtitle' => '0.1in',
 
-
-        'extra_commands'  => array(),
-    );
+        'extra_commands'  => [],
+    ];
   }
-
 }
diff --git a/src/Latex/LatexBase.php b/src/Latex/LatexBase.php
index 0de58c9..1816fae 100644
--- a/src/Latex/LatexBase.php
+++ b/src/Latex/LatexBase.php
@@ -6,30 +6,20 @@
 
 class LatexBase extends LatexParams implements LatexBaseInterface
 {
-  /** @var array */
-  protected $elements = array();
-  /** @var string */
-  protected $fileName;
-  /** @var string */
-  protected $template;
-  /** @var array */
-  protected $dependencies = array();
+  protected array $elements = [];
+  protected string $fileName; // Set in constructor
+  protected ?string $template = null;
+  protected array $dependencies = [];
 
-  /**
-   * @param string $filename
-   */
-  public function __construct($filename)
+  public function __construct(string $filename)
   {
     $this->setFileName($filename);
   }
 
   /**
-   * @param LatexInterface $latexInterface
-   *
-   * @return $this
-   * @throws \Bobv\LatexBundle\Exception\LatexException
+   * @throws LatexException
    */
-  public function addElement(LatexInterface $latexInterface)
+  public function addElement(LatexInterface $latexInterface): self
   {
     if ($latexInterface instanceof LatexBaseInterface) {
       throw new LatexException("A base LaTeX object can not have another base LaTeX object as element!");
@@ -40,89 +30,56 @@ public function addElement(LatexInterface $latexInterface)
     return $this;
   }
 
-  /**
-   * @return array
-   */
-  public function getContext()
+  public function getContext(): array
   {
     return array_merge(
         $this->getParams(),
-        array(
+        [
             'elements' => $this->getElements(),
-        )
+        ]
     );
   }
 
-  /**
-   * @return array
-   */
-  public function getElements()
+  public function getElements(): array
   {
     return $this->elements;
   }
 
-  /**
-   * @param array $elements
-   */
-  public function setElements($elements)
+  public function setElements(array $elements): void
   {
     $this->elements = $elements;
   }
 
-  /**
-   * @return string
-   */
-  public function getFileName()
+  public function getFileName(): string
   {
     return $this->fileName;
   }
 
-  /**
-   * @param string $fileName
-   *
-   * @return LatexBaseInterface $this
-   */
-  public function setFileName($fileName)
+  public function setFileName(string $fileName): self
   {
     $this->fileName = $fileName;
 
     return $this;
   }
 
-  /**
-   * @return string
-   */
-  public function getTemplate()
+  public function getTemplate(): string
   {
     return $this->template;
   }
 
-  /**
-   * @param string $template
-   *
-   * @return LatexBaseInterface $this
-   */
-  public function setTemplate($template)
+  public function setTemplate(string $template): self
   {
     $this->template = $template;
 
     return $this;
   }
 
-  /**
-   * @return array
-   */
-  public function getDependencies()
+  public function getDependencies(): array
   {
     return $this->dependencies;
   }
 
-  /**
-   * @param $dependency
-   *
-   * @return LatexBaseInterface $this
-   */
-  public function addDependency($dependency)
+  public function addDependency(mixed $dependency): self
   {
     $this->dependencies[] = $dependency;
 
@@ -131,12 +88,8 @@ public function addDependency($dependency)
 
   /**
    * To add multiple dependencies locations
-   *
-   * @param $dependencies
-   *
-   * @return LatexBaseInterface
    */
-  public function addDependencies($dependencies)
+  public function addDependencies(iterable $dependencies): self
   {
     foreach ($dependencies as $dependency) {
       $this->addDependency($dependency);
@@ -146,17 +99,12 @@ public function addDependencies($dependencies)
   }
 
   /**
-   * Add an package to include
-   *
-   * @param $package
-   * @param $options
-   *
-   * @return LatexBaseInterface $this
+   * Add a package to include
    */
-  public function addPackage($package, $options = '')
+  public function addPackage(mixed $package, string $options = ''): self
   {
     $matches = array();
-    preg_match_all('/\\\usepackage\{([^}]+)\}/u', $package, $matches);
+    preg_match_all('/\\\usepackage\{([^}]+)}/u', $package, $matches);
     if (count($matches[1]) > 0) {
       $package = $matches[1][0];
     }
@@ -171,12 +119,8 @@ public function addPackage($package, $options = '')
 
   /**
    * Add multiple packages to include (without options)
-   *
-   * @param $packages
-   *
-   * @return mixed
    */
-  public function addPackages($packages)
+  public function addPackages(iterable $packages): self
   {
     foreach ($packages as $package) {
       $this->addPackage($package);
diff --git a/src/Latex/LatexBaseInterface.php b/src/Latex/LatexBaseInterface.php
index 5ea9e08..800d82b 100644
--- a/src/Latex/LatexBaseInterface.php
+++ b/src/Latex/LatexBaseInterface.php
@@ -4,71 +4,41 @@
 
 interface LatexBaseInterface extends LatexInterface
 {
-  /**
-   * Constructor
-   *
-   * @param string $fileName
-   */
-  public function __construct($fileName);
+  public function __construct(string $fileName);
 
   /**
    * Should return the filename for the pdf file
-   *
-   * @return string
    */
-  public function getFileName();
+  public function getFileName(): string;
 
   /**
    * In case you want to change the filename, use this method
-   *
-   * @param string $fileName
-   *
-   * @return LatexBaseInterface
    */
-  public function setFileName($fileName);
+  public function setFileName(string $fileName): self;
 
   /**
    * Should return an array with dependency locations
-   *
-   * @return array
    */
-  public function getDependencies();
+  public function getDependencies(): array;
 
   /**
-   * To add an dependency location
-   *
-   * @param $dependency
-   *
-   * @return LatexBaseInterface
+   * To add a dependency location
    */
-  public function addDependency($dependency);
+  public function addDependency(mixed $dependency): self;
 
   /**
    * To add multiple dependencies locations
-   *
-   * @param $dependencies
-   *
-   * @return LatexBaseInterface
    */
-  public function addDependencies($dependencies);
+  public function addDependencies(iterable $dependencies): self;
 
   /**
-   * Add an package to include
-   *
-   * @param $package
-   * @param $options
-   *
-   * @return LatexBaseInterface $this
+   * Add a package to include
    */
-  public function addPackage($package, $options = '');
+  public function addPackage(mixed $package, string $options = ''): self;
 
   /**
    * Add multiple packages to include (without options)
-   *
-   * @param $packages
-   *
-   * @return mixed
    */
-  public function addPackages($packages);
+  public function addPackages(iterable $packages): self;
 
 }
diff --git a/src/Latex/LatexElement.php b/src/Latex/LatexElement.php
index fcbc88a..832dfa0 100644
--- a/src/Latex/LatexElement.php
+++ b/src/Latex/LatexElement.php
@@ -3,28 +3,19 @@
 
 class LatexElement extends LatexParams implements LatexInterface
 {
-  /** @var string */
-  protected $template;
+  protected string $template;
 
-  public function getContext()
+  public function getContext(): array
   {
     return $this->getParams();
   }
 
-  /**
-   * @return string
-   */
-  public function getTemplate()
+  public function getTemplate(): string
   {
     return $this->template;
   }
 
-  /**
-   * @param string $template
-   *
-   * @return LatexInterface $this
-   */
-  public function setTemplate($template)
+  public function setTemplate(string $template): self
   {
     $this->template = $template;
 
diff --git a/src/Latex/LatexInterface.php b/src/Latex/LatexInterface.php
index 4b758ba..285d8db 100644
--- a/src/Latex/LatexInterface.php
+++ b/src/Latex/LatexInterface.php
@@ -3,52 +3,33 @@
 namespace Bobv\LatexBundle\Latex;
 
 /**
- * Interface LatexInterface
  * All Latex objects should implement this class
- *
- * @package Bobv\LatexBundle\Latex
  */
 interface LatexInterface
 {
-
   /**
    * Needs to return the parameters for the twig render
-   *
-   * @return array
    */
-  public function getContext();
+  public function getContext(): array;
 
   /**
    * Return all set params
-   *
-   * @return array
    */
-  public function getParams();
+  public function getParams(): array;
 
   /**
    * Set a specific param in the context for Twig
-   *
-   * @param string $param
-   * @param mixed $value
-   *
-   * @return LatexInterface
    */
-  public function setParam($param, $value);
+  public function setParam(string $param, mixed $value): self;
 
   /**
    * Should return the twig template
-   *
-   * @return string
    */
-  public function getTemplate();
+  public function getTemplate(): string;
 
   /**
    * In case you want to change the twig template, use this method
-   *
-   * @param string $template
-   *
-   * @return LatexInterface
    */
-  public function setTemplate($template);
+  public function setTemplate(string $template): self;
 
 }
diff --git a/src/Latex/LatexParams.php b/src/Latex/LatexParams.php
index 12be6e8..4515458 100644
--- a/src/Latex/LatexParams.php
+++ b/src/Latex/LatexParams.php
@@ -4,47 +4,37 @@
 use Bobv\LatexBundle\Exception\LatexException;
 
 /**
- * Class LatexContext
  * Use this to predefine the context methods and vars
  *
  * @author BobV
  */
-class LatexParams {
+class LatexParams
+{
+  protected array $params = [];
 
-  /** @var array */
-  protected $params = array();
-
-  /**
-   * Return the params
-   * @return array
-   */
-  public function getParams(){
+  public function getParams(): array {
     return $this->params;
   }
 
   /**
    * Set a specific parameter for the class
    *
-   * @param string $param
-   * @param mixed $value
-   *
-   * @return LatexInterface $this
    * @throws \Bobv\LatexBundle\Exception\LatexException
    */
-  public function setParam($param, $value){
-    if(array_key_exists($param, $this->params)){
+  public function setParam(string $param, mixed $value): LatexInterface {
+    if (array_key_exists($param, $this->params)) {
       // Check if the param is defined as array
-      if(is_array($this->params[$param])){
+      if (is_array($this->params[$param])) {
         // If the value is an array, replace the complete array, else add a new array element
-        if(is_array($value)){
+        if (is_array($value)) {
           $this->params[$param] = $value;
-        }else{
+        } else {
           $this->params[$param][] = $value;
         }
-      }else{
+      } else {
         $this->params[$param] = $value;
       }
-    }else{
+    } else {
       throw new LatexException("The param $param is not defined for " . get_class($this));
     }
     return $this;
diff --git a/src/Latex/LatexSection.php b/src/Latex/LatexSection.php
index 75c58af..9f147f1 100644
--- a/src/Latex/LatexSection.php
+++ b/src/Latex/LatexSection.php
@@ -5,18 +5,13 @@
 
 class LatexSection extends LatexParams implements LatexInterface
 {
-  /** @var array */
-  protected $elements = array();
-  /** @var string */
-  protected $template;
+  protected array $elements = [];
+  protected string $template;
 
   /**
-   * @param LatexInterface $latexInterface
-   *
-   * @return $this
    * @throws \Bobv\LatexBundle\Exception\LatexException
    */
-  public function addElement(LatexInterface $latexInterface)
+  public function addElement(LatexInterface $latexInterface): self
   {
     if ($latexInterface instanceof LatexBaseInterface) {
       throw new LatexException("A base LaTeX object can not have another base LaTeX object as element!");
@@ -27,49 +22,32 @@ public function addElement(LatexInterface $latexInterface)
     return $this;
   }
 
-  /**
-   * @return array
-   */
-  public function getContext()
+  public function getContext(): array
   {
     return array_merge(
         $this->getParams(),
-        array(
+        [
             'elements' => $this->getElements(),
-        )
+        ]
     );
   }
 
-  /**
-   * @return array
-   */
-  public function getElements()
+  public function getElements(): array
   {
     return $this->elements;
   }
 
-  /**
-   * @param array $elements
-   */
-  public function setElements($elements)
+  public function setElements(array $elements): void
   {
     $this->elements = $elements;
   }
 
-  /**
-   * @return string
-   */
-  public function getTemplate()
+  public function getTemplate(): string
   {
     return $this->template;
   }
 
-  /**
-   * @param string $template
-   *
-   * @return LatexInterface $this
-   */
-  public function setTemplate($template)
+  public function setTemplate(string $template): self
   {
     $this->template = $template;
 
diff --git a/src/Latex/Section/Box.php b/src/Latex/Section/Box.php
index 3457df5..99f10f1 100644
--- a/src/Latex/Section/Box.php
+++ b/src/Latex/Section/Box.php
@@ -3,18 +3,18 @@
 
 use Bobv\LatexBundle\Latex\LatexSection;
 
-class Box extends LatexSection {
-
+class Box extends LatexSection
+{
   /**
-   * Constructor of the section section, also defines the default
+   * Constructor of the box section, also defines the default
    */
-  public function __construct(){
+  public function __construct() {
     $this->template = '@BobvLatex/Section/box.tex.twig';
-    $this->params = array(
+    $this->params = [
 
       'newpage' => false, // Standard a section starts on a new page
 
-      'extra_commands' => array(), // Define extra commands at the begin of the section
-    );
+      'extra_commands' => [], // Define extra commands at the beginning of the section
+    ];
   }
 }
diff --git a/src/Latex/Section/MiniPage.php b/src/Latex/Section/MiniPage.php
index eec3e79..aaa7d84 100644
--- a/src/Latex/Section/MiniPage.php
+++ b/src/Latex/Section/MiniPage.php
@@ -5,19 +5,18 @@
 
 class MiniPage extends LatexSection
 {
-
   /**
    * Constructor of the section minipage, also defines the default
    */
   public function __construct()
   {
     $this->template = '@BobvLatex/Section/minipage.tex.twig';
-    $this->params   = array(
+    $this->params   = [
         'width'          => '\textwidth', // Width of the minipage
 
         'newpage'        => false, // Standard a section starts on a new page
 
-        'extra_commands' => array(), // Define extra commands at the begin of the section
-    );
+        'extra_commands' => [], // Define extra commands at the beginning of the section
+    ];
   }
 }
diff --git a/src/Latex/Section/Section.php b/src/Latex/Section/Section.php
index 02a4b30..be91cf5 100644
--- a/src/Latex/Section/Section.php
+++ b/src/Latex/Section/Section.php
@@ -7,18 +7,16 @@ class Section extends LatexSection {
 
   /**
    * Constructor of the section section, also defines the default
-   *
-   * @param string $sectionTitle
    */
-  public function __construct($sectionTitle = ''){
+  public function __construct(string $sectionTitle = ''){
     $this->template = '@BobvLatex/Section/section.tex.twig';
-    $this->params = array(
+    $this->params = [
       'sectionTitle' => $sectionTitle,
       'includeTOC' => true,
 
       'newpage' => true, // Standard a section starts on a new page
 
-      'extra_commands' => array(), // Define extra commands at the begin of the section
-    );
+      'extra_commands' => [], // Define extra commands at the beginning of the section
+    ];
   }
 }
diff --git a/src/Latex/Section/SubSection.php b/src/Latex/Section/SubSection.php
index b6bf962..16732f1 100644
--- a/src/Latex/Section/SubSection.php
+++ b/src/Latex/Section/SubSection.php
@@ -3,22 +3,20 @@
 
 use Bobv\LatexBundle\Latex\LatexSection;
 
-class SubSection extends LatexSection {
-
+class SubSection extends LatexSection
+{
   /**
    * Constructor of the subsection section, also defines the default
-   *
-   * @param string $subsectionTitle
    */
-  public function __construct($subsectionTitle = ''){
+  public function __construct(string $subsectionTitle = '') {
     $this->template = '@BobvLatex/Section/sub_section.tex.twig';
-    $this->params = array(
+    $this->params = [
       'subsectionTitle' => $subsectionTitle,
       'includeTOC' => true,
 
       'newpage' => false, // Standard a subsection does not start on a new page
 
-      'extra_commands' => array(), // Define extra commands at the begin of the section
-    );
+      'extra_commands' => [], // Define extra commands at the beginning of the section
+    ];
   }
 }
diff --git a/src/Latex/Section/SubSubSection.php b/src/Latex/Section/SubSubSection.php
index 03ce9ad..97c4c44 100644
--- a/src/Latex/Section/SubSubSection.php
+++ b/src/Latex/Section/SubSubSection.php
@@ -3,22 +3,20 @@
 
 use Bobv\LatexBundle\Latex\LatexSection;
 
-class SubSubSection extends LatexSection {
-
+class SubSubSection extends LatexSection
+{
   /**
    * Constructor of the subsubsection section, also defines the default
-   *
-   * @param string $subsubsectionTitle
    */
-  public function __construct($subsubsectionTitle = ''){
+  public function __construct(string $subsubsectionTitle = '') {
     $this->template = '@BobvLatex/Section/sub_sub_section.tex.twig';
-    $this->params = array(
+    $this->params = [
       'subsubsectionTitle' => $subsubsectionTitle,
       'includeTOC' => true,
 
       'newpage' => false, // Standard a subsubsection does not start on a new page
 
-      'extra_commands' => array(), // Define extra commands at the begin of the section
-    );
+      'extra_commands' => [], // Define extra commands at the beginning of the section
+    ];
   }
 }
diff --git a/src/Twig/AbstractBobvLatexExtension.php b/src/Twig/AbstractBobvLatexExtension.php
index 959cba4..605e6db 100644
--- a/src/Twig/AbstractBobvLatexExtension.php
+++ b/src/Twig/AbstractBobvLatexExtension.php
@@ -2,12 +2,8 @@
 
 namespace Bobv\LatexBundle\Twig;
 
-if (class_exists('Twig\Extension\AbstractExtension')) {
-    class AbstractBobvLatexExtension extends \Twig\Extension\AbstractExtension
-    {
-    }
-} else {
-    class AbstractBobvLatexExtension extends \Twig_Extension
-    {
-    }
+use Twig\Extension\AbstractExtension;
+
+class AbstractBobvLatexExtension extends AbstractExtension
+{
 }
diff --git a/src/Twig/BobvLatexExtension.php b/src/Twig/BobvLatexExtension.php
index 9088ee7..e8d81ae 100644
--- a/src/Twig/BobvLatexExtension.php
+++ b/src/Twig/BobvLatexExtension.php
@@ -6,28 +6,18 @@
 use function Symfony\Component\String\u;
 
 /**
- * Class BobvLatexExtension
- *
  * @author BobV
  */
 class BobvLatexExtension extends AbstractBobvLatexExtension
 {
+  private Parser $parser; // Set in constructor
 
-  /** @var Parser */
-  private $parser;
-  /** @var bool */
-  private $useSymfonyString;
-
-  public function __construct(bool $useSymfonyString)
+  public function __construct(private readonly bool $useSymfonyString)
   {
-    $this->parser           = new Parser();
-    $this->useSymfonyString = $useSymfonyString;
+    $this->parser = new Parser();
   }
 
-  /**
-   * @return array
-   */
-  public function getFilters()
+  public function getFilters(): array
   {
     $filterClass = class_exists('\\Twig\\TwigFilter') ? '\\Twig\\TwigFilter' : '\\Twig_SimpleFilter';
 
@@ -38,15 +28,12 @@ public function getFilters()
     ];
   }
 
-  /**
-   * @return string
-   */
-  public function getName()
+  public function getName(): string
   {
     return 'bobv_latex_twig_extension';
   }
 
-  private function passThroughSfString($text)
+  private function passThroughSfString(?string $text): ?string
   {
     if (!$this->useSymfonyString) {
       return $text;
@@ -55,12 +42,7 @@ private function passThroughSfString($text)
     return u($text)->ascii()->toString();
   }
 
-  /**
-   * @param string $text
-   *
-   * @return string
-   */
-  public function latexEscape($text, $checkTable = true, $removeLatex = false, $parseNewLines = false, $removeGreek = false)
+  public function latexEscape(?string $text, bool $checkTable = true, bool $removeLatex = false, bool $parseNewLines = false, bool $removeGreek = false): string
   {
     return $this->passThroughSfString(
         $this->parser->parseText($text, $checkTable, $removeLatex, $parseNewLines, $removeGreek)
@@ -69,24 +51,15 @@ public function latexEscape($text, $checkTable = true, $removeLatex = false, $pa
 
   /**
    * Proxy method to set some params for the parseText call
-   *
-   * @param string $text
-   *
-   * @return string
    */
-  public function latexEscapeAll($text)
+  public function latexEscapeAll(?string $text): ?string
   {
     return $this->passThroughSfString(
         $this->parser->parseText($text, false, true, true, true)
     );
   }
 
-  /**
-   * @param string $text
-   *
-   * @return string
-   */
-  public function latexParseHtml($text)
+  public function latexParseHtml(?string $text): ?string
   {
     return $this->passThroughSfString(
         $this->parser::parseHtml($text)