diff --git a/app/HashidsTicketCodeGenerator.php b/app/HashidsTicketCodeGenerator.php
new file mode 100644
index 0000000..026b8ad
--- /dev/null
+++ b/app/HashidsTicketCodeGenerator.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace App;
+
+class HashidsTicketCodeGenerator implements TicketCodeGenerator
+{
+    private $hashids;
+
+    public function __construct($salt)
+    {
+        $this->hashids = new \Hashids\Hashids($salt, 6, 'ABCDEFGHIJKLMNOPQRSTUVWXYZ');
+    }
+
+    public function generateFor($ticket)
+    {
+        return $this->hashids->encode($ticket->id);
+    }
+}
diff --git a/app/TicketCodeGenerator.php b/app/TicketCodeGenerator.php
index 9c6fadd..50771aa 100644
--- a/app/TicketCodeGenerator.php
+++ b/app/TicketCodeGenerator.php
@@ -4,5 +4,5 @@ namespace App;
 
 interface TicketCodeGenerator
 {
-    public function generate();
+    public function generateFor($ticket);
 }
diff --git a/tests/unit/HashidsTicketCodeGeneratorTest.php b/tests/unit/HashidsTicketCodeGeneratorTest.php
new file mode 100644
index 0000000..12f0bc2
--- /dev/null
+++ b/tests/unit/HashidsTicketCodeGeneratorTest.php
@@ -0,0 +1,64 @@
+<?php
+
+use App\Ticket;
+use App\HashidsTicketCodeGenerator;
+use Illuminate\Foundation\Testing\WithoutMiddleware;
+use Illuminate\Foundation\Testing\DatabaseMigrations;
+use Illuminate\Foundation\Testing\DatabaseTransactions;
+
+class HashidsTicketCodeGeneratorTest extends TestCase
+{
+    /** @test */
+    function ticket_codes_are_at_least_6_characters_long()
+    {
+        $ticketCodeGenerator = new HashidsTicketCodeGenerator('testsalt1');
+
+        $code = $ticketCodeGenerator->generateFor(new Ticket(['id' => 1]));
+
+        $this->assertTrue(strlen($code) >= 6);
+    }
+
+    /** @test */
+    function ticket_codes_can_only_contain_uppercase_letters()
+    {
+        $ticketCodeGenerator = new HashidsTicketCodeGenerator('testsalt1');
+
+        $code = $ticketCodeGenerator->generateFor(new Ticket(['id' => 1]));
+
+        $this->assertRegExp('/^[A-Z]+$/', $code);
+    }
+
+    /** @test */
+    function ticket_codes_for_the_same_ticket_id_are_the_same()
+    {
+        $ticketCodeGenerator = new HashidsTicketCodeGenerator('testsalt1');
+
+        $code1 = $ticketCodeGenerator->generateFor(new Ticket(['id' => 1]));
+        $code2 = $ticketCodeGenerator->generateFor(new Ticket(['id' => 1]));
+
+        $this->assertEquals($code1, $code2);
+    }
+
+    /** @test */
+    function ticket_codes_for_different_ticket_ids_are_different()
+    {
+        $ticketCodeGenerator = new HashidsTicketCodeGenerator('testsalt1');
+
+        $code1 = $ticketCodeGenerator->generateFor(new Ticket(['id' => 1]));
+        $code2 = $ticketCodeGenerator->generateFor(new Ticket(['id' => 2]));
+
+        $this->assertNotEquals($code1, $code2);
+    }
+
+    /** @test */
+    function ticket_codes_generated_with_different_salts_are_different()
+    {
+        $ticketCodeGenerator1 = new HashidsTicketCodeGenerator('testsalt1');
+        $ticketCodeGenerator2 = new HashidsTicketCodeGenerator('testsalt2');
+
+        $code1 = $ticketCodeGenerator1->generateFor(new Ticket(['id' => 1]));
+        $code2 = $ticketCodeGenerator2->generateFor(new Ticket(['id' => 1]));
+
+        $this->assertNotEquals($code1, $code2);
+    }
+}