diff --git a/tests/Functional/Infrastructure/Config/JsonConfigProviderTest.php b/tests/Functional/Infrastructure/Config/JsonConfigProviderTest.php
new file mode 100644
index 0000000..3b038f7
--- /dev/null
+++ b/tests/Functional/Infrastructure/Config/JsonConfigProviderTest.php
@@ -0,0 +1,70 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Functional\Infrastructure\Config;
+
+use CuyZ\Valinor\Mapper\TreeMapper;
+use CuyZ\Valinor\MapperBuilder;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+use Runx\Infrastructure\Config\Config;
+use Runx\Infrastructure\Config\Provider\JsonConfigProvider;
+
+#[CoversClass(JsonConfigProvider::class)]
+class JsonConfigProviderTest extends TestCase
+{
+    private string $tmpFile;
+    private TreeMapper $mapper;
+
+    protected function setUp(): void
+    {
+        $this->mapper = (new MapperBuilder())->mapper();
+
+        $this->tmpFile = tempnam(sys_get_temp_dir(), 'cfg_');
+        $configExample = __DIR__ . '/../../../../config/config.example.json';
+
+        if (false === $this->tmpFile) {
+            $this->markTestSkipped('Unable to create temporary config file.');
+        }
+
+        copy($configExample, $this->tmpFile);
+    }
+
+    protected function tearDown(): void
+    {
+        if (is_file($this->tmpFile)) {
+            unlink($this->tmpFile);
+        }
+    }
+
+    public function testThrowsIfFileNotReadable(): void
+    {
+        $provider = new JsonConfigProvider('/non/existent/path.json', $this->mapper);
+
+        $this->expectException(\RuntimeException::class);
+        $this->expectExceptionMessage('not found');
+
+        $provider->getConfig();
+    }
+
+    public function testThrowsOnMappingError(): void
+    {
+        file_put_contents($this->tmpFile, '{"foo":"bar"}');
+
+        $provider = new JsonConfigProvider($this->tmpFile, $this->mapper);
+
+        $this->expectException(\RuntimeException::class);
+        $this->expectExceptionMessage('Failed to map');
+
+        $provider->getConfig();
+    }
+
+    public function testReturnsConfigOnSuccess(): void
+    {
+        $provider = new JsonConfigProvider($this->tmpFile, $this->mapper);
+        $config = $provider->getConfig();
+
+        self::assertInstanceOf(Config::class, $config);
+    }
+}