diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index f701bc8..1e457a7 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -9,7 +9,7 @@ jobs:
 
     strategy:
       matrix:
-        php: [7.4,8.0,8.1]
+        php: [8.1, 8.2]
         dependency-version: [prefer-stable]
 
     name: PHP ${{ matrix.php }} - ${{ matrix.dependency-version }}
@@ -25,3 +25,6 @@ jobs:
 
       - name: Install dependencies
         run: composer update --${{ matrix.dependency-version }} --prefer-dist --no-interaction --no-suggest
+
+      - name: Run tests
+        run: composer test
diff --git a/.github/workflows/php.yml b/.github/workflows/php.yml
new file mode 100644
index 0000000..0a88aac
--- /dev/null
+++ b/.github/workflows/php.yml
@@ -0,0 +1,39 @@
+name: PHP Composer
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Validate composer.json and composer.lock
+      run: composer validate --strict
+
+    - name: Cache Composer packages
+      id: composer-cache
+      uses: actions/cache@v3
+      with:
+        path: vendor
+        key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-php-
+
+    - name: Install dependencies
+      run: composer install --prefer-dist --no-progress
+
+    # Add a test script to composer.json, for instance: "test": "vendor/bin/phpunit"
+    # Docs: https://getcomposer.org/doc/articles/scripts.md
+
+    - name: Run test suite
+      run: composer test
diff --git a/composer.json b/composer.json
index c005884..7745b30 100644
--- a/composer.json
+++ b/composer.json
@@ -18,6 +18,11 @@
             "ShibuyaKosuke\\LaravelYasumi\\": "src/"
         }
     },
+    "autoload-dev": {
+        "psr-4": {
+            "ShibuyaKosuke\\LaravelYasumi\\Tests\\": "tests/"
+        }
+    },
     "extra": {
         "laravel": {
             "providers": [
@@ -27,5 +32,11 @@
                 "Holiday": "ShibuyaKosuke\\LaravelYasumi\\Facades\\Holiday"
             }
         }
+    },
+    "scripts": {
+        "test": "vendor/bin/phpunit"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^10.5"
     }
 }
diff --git a/phpunit.xml b/phpunit.xml
new file mode 100644
index 0000000..c95503b
--- /dev/null
+++ b/phpunit.xml
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" colors="true" bootstrap="vendor/autoload.php" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.5/phpunit.xsd" cacheDirectory=".phpunit.cache">
+  <coverage/>
+  <testsuites>
+    <testsuite name="Application Test Suite">
+      <directory>./tests</directory>
+    </testsuite>
+  </testsuites>
+  <php>
+    <env name="APP_ENV" value="testing"/>
+  </php>
+  <source>
+    <include>
+      <directory suffix=".php">./src</directory>
+    </include>
+  </source>
+</phpunit>
diff --git a/tests/HolidayTest.php b/tests/HolidayTest.php
new file mode 100644
index 0000000..909a1a1
--- /dev/null
+++ b/tests/HolidayTest.php
@@ -0,0 +1,117 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ShibuyaKosuke\LaravelYasumi\Tests;
+
+use Illuminate\Config\Repository;
+use Illuminate\Support\Carbon;
+use ReflectionException;
+use ShibuyaKosuke\LaravelYasumi\Holiday;
+use Yasumi\Exception\MissingTranslationException;
+
+class HolidayTest extends TestCase
+{
+    /**
+     * @dataProvider holidayDataProvider
+     * @return array[]
+     */
+    public static function holidayDataProvider()
+    {
+        return [
+            [ 'Japan', 'ja_JP', '2020-01-01', '元日' ],
+            [ 'Japan', 'ja_JP', '2020-01-13', '成人の日' ],
+            [ 'Japan', 'ja_JP', '2020-02-11', '建国記念の日' ],
+            [ 'Japan', 'ja_JP', '2020-02-23', '天皇誕生日' ],
+            [ 'Japan', 'ja_JP', '2020-02-24', '振替休日 (天皇誕生日)' ],
+            [ 'Japan', 'ja_JP', '2020-03-20', '春分の日' ],
+            [ 'Japan', 'ja_JP', '2020-04-29', '昭和の日' ],
+            [ 'Japan', 'ja_JP', '2020-05-03', '憲法記念日' ],
+            [ 'Japan', 'ja_JP', '2020-05-04', 'みどりの日' ],
+            [ 'Japan', 'ja_JP', '2020-05-05', 'こどもの日' ],
+            [ 'Japan', 'ja_JP', '2020-05-06', '振替休日 (憲法記念日)' ],
+            [ 'Japan', 'ja_JP', '2020-07-23', '海の日' ],
+            [ 'Japan', 'ja_JP', '2020-07-24', 'スポーツの日' ],
+            [ 'Japan', 'ja_JP', '2020-08-10', '山の日' ],
+            [ 'Japan', 'ja_JP', '2020-09-21', '敬老の日' ],
+            [ 'Japan', 'ja_JP', '2020-09-22', '秋分の日' ],
+            [ 'Japan', 'ja_JP', '2020-11-03', '文化の日' ],
+            [ 'Japan', 'ja_JP', '2020-11-23', '勤労感謝の日' ],
+            [ 'Japan', 'ja_JP', '2020-11-23', '勤労感謝の日' ],
+            [ 'Spain', 'es', '2021-01-01', 'Año Nuevo' ],
+            [ 'USA', 'en_US', '2020-01-01', 'New Year’s Day' ],
+            [ 'USA', 'en_US', '2020-01-20', 'Dr. Martin Luther King Jr’s Birthday' ],
+            [ 'USA', 'en_US', '2020-02-17', 'Washington’s Birthday' ],
+            [ 'USA', 'en_US', '2020-05-25', 'Memorial Day' ],
+            [ 'USA', 'en_US', '2020-07-03', 'Independence Day observed' ],
+            [ 'USA', 'en_US', '2020-09-07', 'Labor Day' ],
+            [ 'USA', 'en_US', '2020-10-12', 'Columbus Day' ],
+            [ 'USA', 'en_US', '2020-11-11', 'Veterans Day' ],
+            [ 'USA', 'en_US', '2020-11-26', 'Thanksgiving Day' ],
+            [ 'USA', 'en_US', '2020-12-25', 'Christmas' ],
+        ];
+    }
+    
+    /**
+     * @param string $country
+     * @param string $locale
+     * @param string $date
+     * @param string $expectedHoliday
+     * @throws ReflectionException
+     * @throws MissingTranslationException
+     * @dataProvider holidayDataProvider
+     */
+    public function testCanGetHolidays($country, $locale, $date, $expectedHoliday): void
+    {
+        $config = new Repository([
+            'yasumi' => [
+                'country' => $country,
+                'locale'  => $locale,
+            ],
+        ]);
+        $holiday = new Holiday($config);
+        $newYear = Carbon::make($date);
+        $holidayResult = $holiday->get($newYear);
+        $this->assertEquals($expectedHoliday, $holidayResult);
+    }
+    
+    /**
+     * Test isHoliday method.
+     *
+     * @throws ReflectionException
+     * @throws MissingTranslationException
+     * @dataProvider holidayDataProvider
+     */
+    public function testIsHoliday($country, $locale, $date, $expectedHoliday): void
+    {
+        $config = new Repository([
+            'yasumi' => [
+                'country' => $country,
+                'locale'  => $locale,
+            ],
+        ]);
+        $holiday = new Holiday($config);
+        $newYear = Carbon::make($date);
+        $this->assertTrue($holiday->isHoliday($newYear));
+    }
+    
+    /**
+     * Test isBeforeHoliday method.
+     *
+     * @throws ReflectionException
+     * @throws MissingTranslationException
+     * @dataProvider holidayDataProvider
+     */
+    public function testIsDayBeforeHoliday($country, $locale, $date, $expectedHoliday): void
+    {
+        $config = new Repository([
+            'yasumi' => [
+                'country' => $country,
+                'locale'  => $locale,
+            ],
+        ]);
+        $holiday = new Holiday($config);
+        $newYear = Carbon::make($date)->subDay();
+        $this->assertTrue($holiday->isDayBeforeHoliday($newYear));
+    }
+}
\ No newline at end of file
diff --git a/tests/TestCase.php b/tests/TestCase.php
new file mode 100644
index 0000000..f3261b7
--- /dev/null
+++ b/tests/TestCase.php
@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ShibuyaKosuke\LaravelYasumi\Tests;
+
+abstract class TestCase extends \PHPUnit\Framework\TestCase
+{
+
+}