diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index fd00756..b5b9f8a 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -8,7 +8,7 @@ jobs:
 
     strategy:
       matrix:
-        php: [7.1, 7.2, 7.3, 7.4, 8.0]
+        php: [7.3, 7.4, 8.0]
 
     steps:
     - name: Checkout code
diff --git a/.gitignore b/.gitignore
index 87dc28f..ee17e23 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 vendor
 .idea
 .phpunit.result.cache
+composer.lock
 composer.phar
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 018c1d5..ddda216 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## 1.5
+
+* Removed support for `PHP 7.1` and `PHP 7.2`.
+* Use strict types in the source code.
+
 ## 1.4
 
 * Added **_Fluent Interface_** support, this allows you to add `it`'s and `should`'s chained to a `specify` or `describe`.
diff --git a/LICENSE b/LICENSE
index 525f855..01359eb 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2013-2020 Codeception PHP Testing Framework
+Copyright (c) 2013-2021 Codeception PHP Testing Framework
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
diff --git a/README.md b/README.md
index 393d193..74c4d2a 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ Inspired by MiniTest of Ruby now you combine BDD and classical TDD style in one
 
 ## Installation
 
-*Requires PHP >= 7.1*
+*Requires PHP >= 7.3*
 
 * Install with Composer:
 
diff --git a/VERSION b/VERSION
index 70d5b25..3e1ad72 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.4.3
\ No newline at end of file
+1.5.0
\ No newline at end of file
diff --git a/composer.json b/composer.json
index a2821f2..4b9e0b6 100644
--- a/composer.json
+++ b/composer.json
@@ -14,9 +14,9 @@
         }
     ],
     "require": {
-        "php": ">=7.1.0",
-        "myclabs/deep-copy": "~1.1",
-        "phpunit/phpunit": ">=7.0 <10.0"
+        "php": ">=7.3.0",
+        "myclabs/deep-copy": "^1.10",
+        "phpunit/phpunit": "^8.0|^9.0"
     },
     "autoload": {
         "psr-0": {
diff --git a/src/Codeception/Specify.php b/src/Codeception/Specify.php
index 540a09c..81cfc72 100644
--- a/src/Codeception/Specify.php
+++ b/src/Codeception/Specify.php
@@ -1,4 +1,6 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace Codeception;
 
diff --git a/src/Codeception/Specify/ObjectProperty.php b/src/Codeception/Specify/ObjectProperty.php
index 357c05f..691d342 100644
--- a/src/Codeception/Specify/ObjectProperty.php
+++ b/src/Codeception/Specify/ObjectProperty.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Codeception\Specify;
 
 use ReflectionProperty;
@@ -47,10 +49,7 @@ public function __construct($owner, $property, $value = null)
         $this->initValue = ($value === null ? $this->getValue() : $value);
     }
 
-    /**
-     * @return string
-     */
-    public function getName()
+    public function getName(): string
     {
         return $this->property->getName();
     }
diff --git a/src/Codeception/Specify/ResultPrinter.php b/src/Codeception/Specify/ResultPrinter.php
index e84a006..4ab43be 100644
--- a/src/Codeception/Specify/ResultPrinter.php
+++ b/src/Codeception/Specify/ResultPrinter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Codeception\Specify;
 
 use PHPUnit\TextUI\DefaultResultPrinter;
@@ -10,10 +12,7 @@ class_alias(\PHPUnit\TextUI\ResultPrinter::class, DefaultResultPrinter::class);
 
 class ResultPrinter extends DefaultResultPrinter
 {
-    /**
-     * @param string $progress
-     */
-    protected function writeProgress(string $progress) : void
+    protected function writeProgress(string $progress): void
     {
         $this->write($progress);
         $this->column++;
@@ -25,6 +24,4 @@ protected function writeProgress(string $progress) : void
             }
         }
     }
-
-
 }
diff --git a/src/Codeception/Specify/SpecifyHooks.php b/src/Codeception/Specify/SpecifyHooks.php
index 5f7ab2d..6543c97 100644
--- a/src/Codeception/Specify/SpecifyHooks.php
+++ b/src/Codeception/Specify/SpecifyHooks.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Codeception\Specify;
 
 use Closure;
@@ -29,19 +31,17 @@ trait SpecifyHooks
 
     private $specifyName = '';
 
-    /**
-     * @return SpecifyTest
-     */
-    private function getCurrentSpecifyTest()
+    private function getCurrentSpecifyTest(): SpecifyTest
     {
         return $this->currentSpecifyTest;
     }
+
     /**
      * @param string $specification
      * @param Closure|null $callable
      * @param callable|array $params
      */
-    private function runSpec($specification, Closure $callable = null, $params = [])
+    private function runSpec(string $specification, Closure $callable = null, $params = [])
     {
         if (!$callable) {
             return;
@@ -100,7 +100,7 @@ private function runSpec($specification, Closure $callable = null, $params = [])
      * @param $params
      * @return array
      */
-    private function getSpecifyExamples($params)
+    private function getSpecifyExamples($params): array
     {
         if (isset($params['examples'])) {
             if (!is_array($params['examples'])) {
@@ -111,10 +111,7 @@ private function getSpecifyExamples($params)
         return [[]];
     }
 
-    /**
-     * @return ReflectionClass|null
-     */
-    private function specifyGetPhpUnitReflection()
+    private function specifyGetPhpUnitReflection(): ?ReflectionClass
     {
         if ($this instanceof TestCase) {
             return new ReflectionClass(TestCase::class);
@@ -137,7 +134,7 @@ private function specifyCheckMockObjects()
     /**
      * @param ObjectProperty[] $properties
      */
-    private function specifyRestoreProperties($properties)
+    private function specifyRestoreProperties(array $properties)
     {
         foreach ($properties as $property) {
             $property->restoreValue();
@@ -147,7 +144,7 @@ private function specifyRestoreProperties($properties)
     /**
      * @return ObjectProperty[]
      */
-    private function getSpecifyObjectProperties()
+    private function getSpecifyObjectProperties(): array
     {
         $objectReflection = new ReflectionObject($this);
         $properties = $objectReflection->getProperties();
@@ -184,7 +181,7 @@ private function getSpecifyObjectProperties()
         return $clonedProperties;
     }
 
-    private function specifyGetClassPrivateProperties()
+    private function specifyGetClassPrivateProperties(): array
     {
         static $properties = [];
 
@@ -201,7 +198,7 @@ private function specifyGetClassPrivateProperties()
     /**
      * @param ObjectProperty[] $properties
      */
-    private function specifyCloneProperties($properties)
+    private function specifyCloneProperties(array $properties)
     {
         foreach ($properties as $property) {
             $propertyValue = $property->getValue();
diff --git a/src/Codeception/Specify/SpecifyTest.php b/src/Codeception/Specify/SpecifyTest.php
index b5b470b..383d011 100644
--- a/src/Codeception/Specify/SpecifyTest.php
+++ b/src/Codeception/Specify/SpecifyTest.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Codeception\Specify;
 
 use PHPUnit\Framework\AssertionFailedError;
@@ -33,7 +35,7 @@ public function toString() : string
         return $this->name;
     }
 
-    public function getName($withDataSet = true)
+    public function getName($withDataSet = true): string
     {
         if ($withDataSet && !empty($this->example)) {
             $exporter = new Exporter();
@@ -52,7 +54,7 @@ public function getName($withDataSet = true)
      * The return value is cast to an integer.
      * @since 5.1.0
      */
-    public function count()
+    public function count(): int
     {
         return 1;
     }
diff --git a/tests/ObjectPropertyTest.php b/tests/ObjectPropertyTest.php
index 7cd3e8a..c7e07a6 100644
--- a/tests/ObjectPropertyTest.php
+++ b/tests/ObjectPropertyTest.php
@@ -1,8 +1,10 @@
 <?php
 
+declare(strict_types=1);
+
 use Codeception\Specify\ObjectProperty;
 
-class ObjectPropertyTest extends SpecifyUnitTest
+final class ObjectPropertyTest extends SpecifyUnitTest
 {
     private $private = 'private';
 
diff --git a/tests/SpecifyTest.php b/tests/SpecifyTest.php
index ef32291..717a2df 100644
--- a/tests/SpecifyTest.php
+++ b/tests/SpecifyTest.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 use PHPUnit\Framework\IncompleteTestError;
 
 class SpecifyTest extends SpecifyUnitTest
diff --git a/tests/_bootstrap.php b/tests/_bootstrap.php
index eea7599..6232bc4 100644
--- a/tests/_bootstrap.php
+++ b/tests/_bootstrap.php
@@ -1,3 +1,4 @@
 <?php
+
 require_once __DIR__.'/../vendor/autoload.php';
 require_once __DIR__ . '/_support/SpecifyUnitTest.php';
diff --git a/tests/_support/SpecifyUnitTest.php b/tests/_support/SpecifyUnitTest.php
index ad7b51a..3a4ff93 100644
--- a/tests/_support/SpecifyUnitTest.php
+++ b/tests/_support/SpecifyUnitTest.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 use PHPUnit\Framework\TestCase;
 
 class SpecifyUnitTest extends TestCase