diff --git a/src/TempMailBuster.php b/src/TempMailBuster.php
new file mode 100644
index 0000000..a291088
--- /dev/null
+++ b/src/TempMailBuster.php
@@ -0,0 +1,70 @@
+<?php
+namespace Ely\TempMailBuster;
+
+class TempMailBuster
+{
+    /**
+     * @var Storage
+     */
+    private $storage;
+
+    /**
+     * @return Storage
+     */
+    public function getStorage()
+    {
+        return $this->storage;
+    }
+
+    /**
+     * Validate passed email over all storage domains and return true if domain not found
+     * in lists. False otherwise.
+     * @see TempMailBuster::getDomain() for info about accepted $email formats
+     *
+     * @param string $email
+     * @return bool
+     */
+    public function validate($email)
+    {
+        $domain = $this->getDomain($email);
+        $tempMailsRegex = $this->buildRegex($this->getStorage()->getBlacklist());
+        $match = preg_match($tempMailsRegex, $domain);
+
+        // TODO: add support for whitelists
+
+        return !$match;
+    }
+
+    /**
+     * Catches the domain part of passed E-mail address. Expected values is:
+     * - full E-mail: erickskrauch@ely.by
+     * - domain, starting with @: @ely.by
+     * - domain itself: ely.by
+     *
+     * @param string $email
+     * @return string
+     */
+    protected function getDomain($email)
+    {
+        $parts = explode('@', $email);
+        return array_pop($parts);
+    }
+
+    /**
+     * @param array $list
+     *
+     * @return string
+     */
+    protected function buildRegex(array $list)
+    {
+        return '/^(' . implode('|', $list) . ')$/';
+    }
+
+    /**
+     * @param Storage $storage
+     */
+    public function __construct(Storage $storage)
+    {
+        $this->storage = $storage;
+    }
+}
diff --git a/tests/StorageTest.php b/tests/StorageTest.php
index f38dc27..30fa9e9 100644
--- a/tests/StorageTest.php
+++ b/tests/StorageTest.php
@@ -12,18 +12,18 @@ class StorageTest extends \PHPUnit_Framework_TestCase
     public function testAppendToBlacklist()
     {
         $storage = new Storage(['item1']);
-        $storage->appendToBlacklist(['item2']);
+        $this->assertEquals($storage, $storage->appendToBlacklist(['item2']));
         $this->assertEquals(['item1', 'item2'], $storage->getBlacklist());
 
         $storage = new Storage(['item1']);
-        $storage->appendToBlacklist('item2');
+        $this->assertEquals($storage, $storage->appendToBlacklist('item2'));
         $this->assertEquals(['item1', 'item2'], $storage->getBlacklist());
     }
 
     public function testSetBlacklist()
     {
         $storage = new Storage(['item1']);
-        $storage->setBlacklist(['item2']);
+        $this->assertEquals($storage, $storage->setBlacklist(['item2']));
         $this->assertEquals(['item2'], $storage->getBlacklist());
     }
 }
diff --git a/tests/TempMailBusterTest.php b/tests/TempMailBusterTest.php
new file mode 100644
index 0000000..54355e4
--- /dev/null
+++ b/tests/TempMailBusterTest.php
@@ -0,0 +1,54 @@
+<?php
+namespace Ely\TempMailBuster;
+
+class TempMailBusterTest extends \PHPUnit_Framework_TestCase
+{
+    public function testGetStorage()
+    {
+        $storage = new Storage(['test']);
+        $object = new TempMailBuster($storage);
+        $this->assertEquals($storage, $object->getStorage());
+    }
+
+    public function testGetDomain()
+    {
+        $object = new TempMailBuster(new Storage());
+        $this->assertEquals('ely.by', $this->callGetDomain($object, 'erickskrauch@ely.by'));
+        $this->assertEquals('ely.by', $this->callGetDomain($object, '@ely.by'));
+        $this->assertEquals('ely.by', $this->callGetDomain($object, 'ely.by'));
+    }
+
+    public function testBuildRegex()
+    {
+        $object = new TempMailBuster(new Storage());
+        $this->assertEquals('/^(simple)$/', $this->callBuildRegex($object, ['simple']));
+        $this->assertEquals('/^(simple|another)$/', $this->callBuildRegex($object, ['simple', 'another']));
+    }
+
+    public function testValidate()
+    {
+        $storage = new Storage(['mojang\.com']);
+        $object = new TempMailBuster($storage);
+        $this->assertFalse($object->validate('notch@mojang.com'));
+        $this->assertTrue($object->validate('jeb@mojang1.com'));
+        $this->assertTrue($object->validate('erickskrauch@ely.by'));
+    }
+
+    private function callGetDomain($object, $email)
+    {
+        $class = new \ReflectionClass($object);
+        $method = $class->getMethod('getDomain');
+        $method->setAccessible(true);
+
+        return $method->invokeArgs($object, [$email]);
+    }
+
+    private function callBuildRegex($object, array $list)
+    {
+        $class = new \ReflectionClass($object);
+        $method = $class->getMethod('buildRegex');
+        $method->setAccessible(true);
+
+        return $method->invokeArgs($object, [$list]);
+    }
+}