diff --git a/tests/Roles.php b/tests/Roles.php
new file mode 100644
index 0000000..2a876aa
--- /dev/null
+++ b/tests/Roles.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace distinctm\LaravelDataSync\Tests;
+
+use Illuminate\Database\Eloquent\Model;
+
+class Roles extends Model
+{
+    public $timestamps = false;
+
+    protected $guarded = [];
+
+    public function supervisor()
+    {
+        return $this->belongsTo(Supervisor::class);
+    }
+}
\ No newline at end of file
diff --git a/tests/Supervisor.php b/tests/Supervisor.php
new file mode 100644
index 0000000..1272458
--- /dev/null
+++ b/tests/Supervisor.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace distinctm\LaravelDataSync\Tests;
+
+use Illuminate\Database\Eloquent\Model;
+
+class Supervisor extends Model
+{
+    public $timestamps = false;
+
+    protected $guarded = [];
+
+    public function roles()
+    {
+        return $this->hasMany(Roles::class);
+    }
+}
\ No newline at end of file
diff --git a/tests/TestCase.php b/tests/TestCase.php
new file mode 100644
index 0000000..9dfd32a
--- /dev/null
+++ b/tests/TestCase.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace distinctm\LaravelDataSync\Tests;
+
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+class TestCase extends \Orchestra\Testbench\TestCase
+{
+    protected function getEnvironmentSetUp($app)
+    {
+        $app['config']->set('database.default', 'testdb');
+        $app['config']->set('database.connections.testdb', [
+            'driver' => 'sqlite',
+            'database' => ':memory:'
+        ]);
+    }
+
+    protected function setUp()
+    {
+        parent::setUp();
+
+        Schema::create('supervisors', function (Blueprint $table) {
+            $table->increments('id');
+            $table->string('name');
+        });
+
+        Schema::create('roles', function (Blueprint $table) {
+            $table->increments('id');
+            $table->string('slug');
+            $table->unsignedInteger('supervisor_id')->nullable();
+            $table->string('category')->nullable();
+        });
+    }
+}
\ No newline at end of file
diff --git a/tests/Unit/UpdaterTest.php b/tests/Unit/UpdaterTest.php
new file mode 100644
index 0000000..74cdcab
--- /dev/null
+++ b/tests/Unit/UpdaterTest.php
@@ -0,0 +1,106 @@
+<?php
+
+namespace distinctm\LaravelDataSync\Tests;
+
+use distinctm\LaravelDataSync\Tests\Fakes\UpdaterFake;
+use Exception;
+
+class UpdaterTest extends TestCase
+{
+    /** @test */
+    public function it_adds_roles_to_the_database()
+    {
+        $updater = new UpdaterFake(__DIR__ . '/../test-data', 'roles');
+
+        $updater->run();
+
+        $this->assertDatabaseHas('roles', ['slug' => 'update-student-records']);
+        $this->assertDatabaseHas('roles', ['slug' => 'borrow-ferrari']);
+        $this->assertDatabaseHas('roles', ['slug' => 'destroy-ferrari']);
+    }
+
+    /** @test */
+    public function it_can_default_to_configuration()
+    {
+        config()->set('data-sync.path', __DIR__ . '/../test-data');
+
+        $updater = new UpdaterFake();
+
+        $updater->run();
+
+        $this->assertDatabaseHas('roles', ['slug' => 'update-student-records']);
+        $this->assertDatabaseHas('roles', ['slug' => 'borrow-ferrari']);
+        $this->assertDatabaseHas('roles', ['slug' => 'destroy-ferrari']);
+    }
+
+    /** @test */
+    public function it_can_update_an_existing_record()
+    {
+        config()->set('data-sync.path', __DIR__ . '/../test-data');
+        (new UpdaterFake())->run();
+
+        config()->set('data-sync.path', __DIR__ . '/../test-data/valid');
+        (new UpdaterFake())->run();
+
+        $this->assertDatabaseHas('roles', ['category' => 'changed']);
+        $this->assertDatabaseHas('roles', ['category' => 'changed']);
+        $this->assertDatabaseHas('roles', ['category' => 'changed']);
+    }
+
+    /** @test */
+    public function it_can_update_the_relationship()
+    {
+        $supervisor = Supervisor::create([
+            'name' => 'CEO',
+        ]);
+
+        config()->set('data-sync.path', __DIR__ . '/../test-data/relationship', 'roles');
+        (new UpdaterFake())->run();
+
+        $this->assertEquals($supervisor->id, Roles::first()->supervisor_id);
+        $this->assertTrue($supervisor->is(Roles::first()->supervisor));
+    }
+
+    /** @test */
+    public function exception_is_thrown_if_the_directory_does_not_exists()
+    {
+        try {
+            new UpdaterFake();
+
+            $this->fail('exception was thrown');
+
+        } catch (Exception $e) {
+            $this->assertEquals('Specified sync file directory does not exist', $e->getMessage());
+        }
+    }
+    
+    /** @test */
+    public function invalid_json_throws_an_exception()
+    {
+        try {
+            $updater = new UpdaterFake(__DIR__ . '/../test-data/invalid-json');
+            $updater->run();
+
+            $this->fail('exception was thrown');
+
+        } catch (Exception $e) {
+            $this->assertContains('No records or invalid JSON for', $e->getMessage());
+        }
+
+    }
+
+    /** @test */
+    public function the_json_must_contain_a_key_with_an_underscore()
+    {
+        try {
+            $updater = new UpdaterFake(__DIR__ . '/../test-data/no-criteria');
+            $updater->run();
+
+            $this->fail('exception was thrown');
+
+        } catch (Exception $e) {
+           $this->assertEquals('No criteria/attributes detected', $e->getMessage());
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/tests/fakes/UpdaterFake.php b/tests/fakes/UpdaterFake.php
new file mode 100644
index 0000000..070616d
--- /dev/null
+++ b/tests/fakes/UpdaterFake.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace distinctm\LaravelDataSync\Tests\Fakes;
+
+use distinctm\LaravelDataSync\Updater;
+
+class UpdaterFake extends Updater
+{
+    protected function getModel(string $name)
+    {
+        return '\\distinctm\\LaravelDataSync\\Tests\\' . studly_case(
+            pathinfo($name, PATHINFO_FILENAME)
+        );
+    }
+}
\ No newline at end of file
diff --git a/tests/test-data/invalid-json/invalid.json b/tests/test-data/invalid-json/invalid.json
new file mode 100644
index 0000000..c44dc44
--- /dev/null
+++ b/tests/test-data/invalid-json/invalid.json
@@ -0,0 +1,3 @@
+[
+
+]
\ No newline at end of file
diff --git a/tests/test-data/no-criteria/no-criteria.json b/tests/test-data/no-criteria/no-criteria.json
new file mode 100644
index 0000000..948fe90
--- /dev/null
+++ b/tests/test-data/no-criteria/no-criteria.json
@@ -0,0 +1,5 @@
+[
+    {
+        "string": "update-student-records"
+    }
+]
\ No newline at end of file
diff --git a/tests/test-data/relationship/roles.json b/tests/test-data/relationship/roles.json
new file mode 100644
index 0000000..b1b0c7b
--- /dev/null
+++ b/tests/test-data/relationship/roles.json
@@ -0,0 +1,9 @@
+[
+    {
+        "_slug": "update-student-records",
+        "category": "testing",
+        "supervisor": {
+            "name": "CEO"
+        }
+    }
+]
\ No newline at end of file
diff --git a/tests/test-data/roles.json b/tests/test-data/roles.json
new file mode 100644
index 0000000..d33fe9a
--- /dev/null
+++ b/tests/test-data/roles.json
@@ -0,0 +1,14 @@
+[
+    {
+        "_slug": "update-student-records",
+        "category": "testing"
+    },
+    {
+        "_slug": "borrow-ferrari",
+        "category": "cars"
+    },
+    {
+        "_slug": "destroy-ferrari",
+        "category": "cars"
+    }
+]
\ No newline at end of file
diff --git a/tests/test-data/valid/roles.json b/tests/test-data/valid/roles.json
new file mode 100644
index 0000000..8f0dffe
--- /dev/null
+++ b/tests/test-data/valid/roles.json
@@ -0,0 +1,14 @@
+[
+    {
+        "_slug": "update-student-records",
+        "category": "changed"
+    },
+    {
+        "_slug": "borrow-ferrari",
+        "category": "changed"
+    },
+    {
+        "_slug": "destroy-ferrari",
+        "category": "changed"
+    }
+]
\ No newline at end of file