diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 41cef6c..c492e7a 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php-version: ['5.3', '5.4', '5.5', '5.6', '7.0', '7.1', '7.2', '7.3', '7.4']
+        php-version: ['5.3', '5.4', '5.5', '5.6', '7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1']
     steps:
     - name: Checkout
       uses: actions/checkout@v2
@@ -23,7 +23,7 @@ jobs:
     - name: Run Tests
       run: vendor/bin/phpunit --coverage-clover ./coverage.xml
     - name: Upload Coverage
-      if: ${{ matrix.php-version == '7.4' }}
+      if: ${{ matrix.php-version == '8.1' }}
       uses: codecov/codecov-action@v1
       with:
         file: ./coverage.xml
diff --git a/LICENSE b/LICENSE
index 80b6dad..cc7838a 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2014, 2015, 2016, 2017, 2018, 2019, 2020 Josh Sherman
+Copyright (c) 2014-2022 Josh Sherman
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/composer.json b/composer.json
index 9300c87..a28a4b3 100644
--- a/composer.json
+++ b/composer.json
@@ -1,29 +1,34 @@
 {
-  "name": "joshtronic/php-loremipsum",
-  "description": "Lorem ipsum generator in PHP without dependencies",
-  "version": "1.0.6",
-  "type": "library",
-  "keywords": [
-    "lorem",
-    "ipsum",
-    "generator"
-  ],
-  "homepage": "https://github.com/joshtronic/php-loremipsum",
-  "license": "MIT",
-  "authors": [{
-    "name": "Josh Sherman",
-    "email": "hello@joshtronic.com",
-    "homepage": "https://joshtronic.com"
-  }],
-  "require": {
-    "php": ">=5.3"
-  },
-  "require-dev": {
-    "phpunit/phpunit": ">=4"
-  },
-  "autoload": {
-    "psr-4": {
-      "joshtronic\\": "src/"
+    "name": "joshtronic/php-loremipsum",
+    "description": "Lorem ipsum generator in PHP without dependencies",
+    "version": "2.1.0",
+    "type": "library",
+    "keywords": [
+      "lorem",
+      "ipsum",
+      "generator"
+    ],
+    "homepage": "https://github.com/joshtronic/php-loremipsum",
+    "license": "MIT",
+    "authors": [{
+      "name": "Josh Sherman",
+      "email": "hello@joshtronic.com",
+      "homepage": "https://joshtronic.com"
+    }],
+    "require": {
+      "php": ">=5.3"
+    },
+    "require-dev": {
+      "phpunit/phpunit": "^4.8.36 || ^9.0"
+    },
+    "autoload": {
+      "psr-4": {
+        "joshtronic\\": "src/"
+      }
+    },
+    "autoload-dev": {
+      "psr-4": {
+        "joshtronic\\Tests\\": "tests/"
+      }
     }
   }
-}
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..0292a3b
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,14 @@
+parameters:
+
+    paths:
+        - src
+
+    # The level 8 is the highest level
+    level: max
+
+    excludePaths:
+        - ./*/*/FileToBeExcluded.php
+
+    checkMissingIterableValueType: true
+
+    #editorUrl: 'vscode://file/%%file%%:%%line%%'
diff --git a/phpunit.xml b/phpunit.xml
index eea8f91..8fe6c98 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit
+  bootstrap="vendor/autoload.php"
   colors="true"
   convertErrorsToExceptions="true"
   convertNoticesToExceptions="true"
diff --git a/src/LoremIpsum.php b/src/LoremIpsum.php
index 6db3cb6..863b8d5 100644
--- a/src/LoremIpsum.php
+++ b/src/LoremIpsum.php
@@ -9,7 +9,7 @@
  * Redistribution of these files must retain the above copyright notice.
  *
  * @author    Josh Sherman <hello@joshtronic.com>
- * @copyright Copyright 2014, 2015, 2016, 2017, 2018, 2019, 2020 Josh Sherman
+ * @copyright Copyright 2014-2022 Josh Sherman
  * @license   http://www.opensource.org/licenses/mit-license.html
  * @link      https://github.com/joshtronic/php-loremipsum
  */
@@ -24,7 +24,7 @@ class LoremIpsum
      * Whether or not we should be starting the string with "Lorem ipsum..."
      *
      * @access private
-     * @var    boolean
+     * @var    mixed
      */
     private $first = true;
 
@@ -35,9 +35,9 @@ class LoremIpsum
      * a complete list exists and if so, where to get it.
      *
      * @access private
-     * @var    array
+     * @var    array<string>
      */
-    public $words = array(
+    private $words = array(
         // Lorem ipsum...
         'lorem', 'ipsum', 'dolor', 'sit', 'amet', 'consectetur', 'adipiscing', 'elit',
 
@@ -83,7 +83,7 @@ class LoremIpsum
      */
     public function word($tags = false)
     {
-        return $this->words(1, $tags);
+        return strval($this->words(1, $tags));
     }
 
     /**
@@ -94,7 +94,7 @@ class LoremIpsum
      * @access public
      * @param  integer $count how many words to generate
      * @param  mixed   $tags string or array of HTML tags to wrap output with
-     * @return array   generated lorem ipsum words
+     * @return mixed  generated lorem ipsum words
      */
     public function wordsArray($count = 1, $tags = false)
     {
@@ -114,6 +114,7 @@ class LoremIpsum
      */
     public function words($count = 1, $tags = false, $array = false)
     {
+        $count      = (int) $count;
         $words      = array();
         $word_count = 0;
 
@@ -151,7 +152,7 @@ class LoremIpsum
      */
     public function sentence($tags = false)
     {
-        return $this->sentences(1, $tags);
+        return strval($this->sentences(1, $tags));
     }
 
     /**
@@ -162,7 +163,7 @@ class LoremIpsum
      * @access public
      * @param  integer $count how many sentences to generate
      * @param  mixed   $tags string or array of HTML tags to wrap output with
-     * @return array   generated lorem ipsum sentences
+     * @return mixed   generated lorem ipsum sentences
      */
     public function sentencesArray($count = 1, $tags = false)
     {
@@ -204,7 +205,7 @@ class LoremIpsum
      */
     public function paragraph($tags = false)
     {
-        return $this->paragraphs(1, $tags);
+        return strval($this->paragraphs(1, $tags));
     }
 
     /**
@@ -215,15 +216,18 @@ class LoremIpsum
      * @access public
      * @param  integer $count how many paragraphs to generate
      * @param  mixed   $tags string or array of HTML tags to wrap output with
-     * @return array   generated lorem ipsum paragraphs
+     * @return array<string>   generated lorem ipsum paragraphs
      */
     public function paragraphsArray($count = 1, $tags = false)
     {
+        // The $array parameter set to true means an array is returned.
+        // Return type is mixed, we should probably cast to array.
+        // @phpstan-ignore-next-line
         return $this->paragraphs($count, $tags, true);
     }
 
     /**
-     * Paragraphss
+     * Paragraphs
      *
      * Generates paragraphs of lorem ipsum.
      *
@@ -238,10 +242,13 @@ class LoremIpsum
         $paragraphs = array();
 
         for ($i = 0; $i < $count; $i++) {
-            $paragraphs[] = $this->sentences($this->gauss(5.8, 1.93));
+            $paragraphs[] = strval($this->sentences($this->gauss(5.8, 1.93)));
         }
 
-        return $this->output($paragraphs, $tags, $array, "\n\n");
+        if ($array) {
+            return $this->output($paragraphs, $tags, $array, "\n\n");
+        }
+        return strval($this->output($paragraphs, $tags, false, "\n\n"));
     }
 
     /**
@@ -255,7 +262,7 @@ class LoremIpsum
      * @access private
      * @param  double  $mean average value
      * @param  double  $std_dev stadnard deviation
-     * @return double  calculated distribution
+     * @return int  calculated distribution
      */
     private function gauss($mean, $std_dev)
     {
@@ -263,7 +270,7 @@ class LoremIpsum
         $y = mt_rand() / mt_getrandmax();
         $z = sqrt(-2 * log($x)) * cos(2 * pi() * $y);
 
-        return $z * $std_dev + $mean;
+        return intval($z * $std_dev + $mean);
     }
 
     /**
@@ -273,6 +280,7 @@ class LoremIpsum
      * the first time we are generating the text.
      *
      * @access private
+     * @return void
      */
     private function shuffle()
     {
@@ -298,18 +306,18 @@ class LoremIpsum
      * first word of the sentence.
      *
      * @access private
-     * @param  array   $sentences the sentences we would like to punctuate
+     * @param  array<string>   $sentences the sentences we would like to punctuate
+     * @return void
      */
     private function punctuate(&$sentences)
     {
         foreach ($sentences as $key => $sentence) {
             $words = count($sentence);
-
             // Only worry about commas on sentences longer than 4 words
             if ($words > 4) {
                 $mean    = log($words, 6);
                 $std_dev = $mean / 6;
-                $commas  = round($this->gauss($mean, $std_dev));
+                $commas  = $this->gauss($mean, $std_dev);
 
                 for ($i = 1; $i <= $commas; $i++) {
                     $word = round($i * $words / ($commas + 1));
@@ -333,7 +341,7 @@ class LoremIpsum
      * into a string or not.
      *
      * @access private
-     * @param  array   $strings an array of generated strings
+     * @param  array<string>   $strings an array of generated strings
      * @param  mixed   $tags string or array of HTML tags to wrap output with
      * @param  boolean $array whether an array or a string should be returned
      * @param  string  $delimiter the string to use when calling implode()
@@ -351,11 +359,13 @@ class LoremIpsum
 
             foreach ($strings as $key => $string) {
                 foreach ($tags as $tag) {
-                    // Detects / applies back reference
-                    if ($tag[0] == '<') {
-                        $string = str_replace('$1', $string, $tag);
-                    } else {
-                        $string = sprintf('<%1$s>%2$s</%1$s>', $tag, $string);
+                    if (is_string($tag)) {
+                        // Detects / applies back reference
+                        if ($tag[0] == '<') {
+                            $string = str_replace('$1', $string, $tag);
+                        } else {
+                            $string = sprintf('<%1$s>%2$s</%1$s>', $tag, $string);
+                        }
                     }
 
                     $strings[$key] = $string;
@@ -370,4 +380,3 @@ class LoremIpsum
         return $strings;
     }
 }
-
diff --git a/tests/LoremIpsumTest.php b/tests/LoremIpsumTest.php
index e05ffbb..77c5906 100644
--- a/tests/LoremIpsumTest.php
+++ b/tests/LoremIpsumTest.php
@@ -1,139 +1,198 @@
 <?php
-require_once './src/LoremIpsum.php';
+namespace joshtronic\Tests;
+use joshtronic\LoremIpsum;
+use PHPUnit\Framework\TestCase;
 
-if (
-    !class_exists('\PHPUnit_Framework_TestCase')
-    && class_exists('\PHPUnit\Framework\TestCase')
-) {
-    class_alias('\PHPUnit\Framework\TestCase', '\PHPUnit_Framework_TestCase');
-}
-
-class LoremIpsumTest extends PHPUnit_Framework_TestCase
+class LoremIpsumTest extends TestCase
 {
-    public function testWord()
-    {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp('/^[a-z]+$/i', $lipsum->word());
+    /**
+     * @doesNotPerformAssertions
+     */
+    public function testAssertRegExp() {
+        if (version_compare(PHP_VERSION, '7.3.0', '>=')) {
+            return 'assertMatchesRegularExpression';
+        }
+
+        return 'assertRegExp';
     }
 
-    public function testWords()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testWord($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp(
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp('/^[a-z]+$/i', $lipsum->word());
+    }
+
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testWords($assertRegExp)
+    {
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp(
             '/^[a-z]+ [a-z]+ [a-z]+$/i',
             $lipsum->words(3)
         );
     }
 
-    public function testWordsArray()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testWordsArray($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
+        $lipsum = new LoremIpsum();
         $words = $lipsum->wordsArray(3);
         $this->assertTrue(is_array($words));
         $this->assertCount(3, $words);
 
         foreach ($words as $word) {
-            $this->assertRegExp('/^[a-z]+$/i', $word);
+            $this->$assertRegExp('/^[a-z]+$/i', $word);
         }
     }
 
-    public function testWordsExceedingVocab()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testWordsExceedingVocab($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
+        $lipsum = new LoremIpsum();
         $this->assertCount(500, $lipsum->wordsArray(500));
     }
 
-    public function testSentence()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testSentence($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp('/^[a-z, ]+\.$/i', $lipsum->sentence());
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp('/^[a-z, ]+\.$/i', $lipsum->sentence());
     }
 
-    public function testSentences()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testSentences($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp(
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp(
             '/^[a-z, ]+\. [a-z, ]+\. [a-z, ]+\.$/i',
             $lipsum->sentences(3)
         );
     }
 
-    public function testSentencesArray()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testSentencesArray($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
+        $lipsum = new LoremIpsum();
         $sentences = $lipsum->sentencesArray(3);
         $this->assertTrue(is_array($sentences));
         $this->assertCount(3, $sentences);
 
         foreach ($sentences as $sentence) {
-            $this->assertRegExp('/^[a-z, ]+\.$/i', $sentence);
+            $this->$assertRegExp('/^[a-z, ]+\.$/i', $sentence);
         }
     }
 
-    public function testParagraph()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testParagraph($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp('/^([a-z, ]+\.)+$/i', $lipsum->paragraph());
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp('/^([a-z, ]+\.)+$/i', $lipsum->paragraph());
     }
 
-    public function testParagraphs()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testParagraphs($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp(
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp(
             '/^([a-z, ]+\.)+\n\n([a-z, ]+\.)+\n\n([a-z, ]+\.)+$/i',
             $lipsum->paragraphs(3)
         );
     }
 
-    public function testParagraphsArray()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testParagraphsArray($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
+        $lipsum = new LoremIpsum();
         $paragraphs = $lipsum->paragraphsArray(3);
         $this->assertTrue(is_array($paragraphs));
         $this->assertCount(3, $paragraphs);
 
         foreach ($paragraphs as $paragraph) {
-            $this->assertRegExp('/^([a-z, ]+\.)+$/i', $paragraph);
+            $this->$assertRegExp('/^([a-z, ]+\.)+$/i', $paragraph);
         }
     }
 
-    public function testMarkupString()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testMarkupString($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp(
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp(
             '/^<li>[a-z]+<\/li>$/i',
             $lipsum->word('li')
         );
     }
 
-    public function testMarkupArray()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testMarkupArray($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp(
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp(
             '/^<div><p>[a-z]+<\/p><\/div>$/i',
             $lipsum->word(array('div', 'p'))
         );
     }
 
-    public function testMarkupBackReference()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testMarkupBackReference($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
-        $this->assertRegExp(
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp(
             '/^<li><a href="[a-z]+">[a-z]+<\/a><\/li>$/i',
             $lipsum->word('<li><a href="$1">$1</a></li>')
         );
     }
 
-    public function testMarkupArrayReturn()
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testMarkupArrayReturn($assertRegExp)
     {
-        $lipsum = new joshtronic\LoremIpsum();
+        $lipsum = new LoremIpsum();
         $words = $lipsum->wordsArray(3, 'li');
         $this->assertTrue(is_array($words));
         $this->assertCount(3, $words);
 
         foreach ($words as $word) {
-            $this->assertRegExp('/^<li>[a-z]+<\/li>$/i', $word);
+            $this->$assertRegExp('/^<li>[a-z]+<\/li>$/i', $word);
         }
     }
+
+    /**
+     * @depends testAssertRegExp
+     */
+    public function testSkipNonStringTag($assertRegExp)
+    {
+        $lipsum = new LoremIpsum();
+        $this->$assertRegExp('/^[a-z]+$/i', $lipsum->word(123));
+        $this->$assertRegExp('/^[a-z]+$/i', $lipsum->word(array(1, 2, 3)));
+        $this->$assertRegExp('/^[a-z]+$/i', $lipsum->word(true));
+    }
 }