diff --git a/src/Zipkin/Reporters/Http.php b/src/Zipkin/Reporters/Http.php
index 5888c7d7..98e73e35 100644
--- a/src/Zipkin/Reporters/Http.php
+++ b/src/Zipkin/Reporters/Http.php
@@ -36,7 +36,7 @@ public function __construct(
     ) {
         $this->clientFactory = $requesterFactory ?: CurlFactory::create();
         $this->options = array_merge(self::DEFAULT_OPTIONS, $options);
-        $this->reportMetrics = $reporterMetrics;
+        $this->reportMetrics = $reporterMetrics ?: new NoopMetrics();
     }
 
     /**
diff --git a/src/Zipkin/Reporters/Http/CurlFactory.php b/src/Zipkin/Reporters/Http/CurlFactory.php
index 81768cd3..ab47e298 100644
--- a/src/Zipkin/Reporters/Http/CurlFactory.php
+++ b/src/Zipkin/Reporters/Http/CurlFactory.php
@@ -7,6 +7,10 @@
 
 final class CurlFactory implements ClientFactory
 {
+    private function __construct()
+    {
+    }
+
     /**
      * @return CurlFactory
      * @throws \BadFunctionCallException if the curl extension is not installed.
diff --git a/tests/Unit/Reporters/HttpTest.php b/tests/Unit/Reporters/HttpTest.php
index 1c9e2abf..327dc364 100644
--- a/tests/Unit/Reporters/HttpTest.php
+++ b/tests/Unit/Reporters/HttpTest.php
@@ -16,6 +16,12 @@ final class HttpTest extends PHPUnit_Framework_TestCase
     const PAYLOAD = '[{"id":"%s","name":null,"traceId":"%s","parentId":null,'
         . '"timestamp":null,"duration":null,"debug":false,"localEndpoint":{"serviceName":""}}]';
 
+    public function testCreateHttpReporterWithDefaultDependencies()
+    {
+        $httpReporter = new Http();
+        $this->assertInstanceOf(Http::class, $httpReporter);
+    }
+
     public function testHttpReporterSuccess()
     {
         $context = TraceContext::createAsRoot();