diff --git a/composer.json b/composer.json
index d0d5e4e..53ebcff 100644
--- a/composer.json
+++ b/composer.json
@@ -14,6 +14,9 @@
         "psr-4": { "React\\Promise\\Stream\\" : "src/" },
         "files": [ "src/functions_include.php" ]
     },
+    "autoload-dev": {
+        "psr-4": { "React\\Tests\\Promise\\Stream\\": "tests/" }
+    },
     "require": {
         "php": ">=5.3",
         "react/stream": "^1.0 || ^0.7 || ^0.6 || ^0.5 || ^0.4 || ^0.3",
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 9195bac..f373698 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<phpunit bootstrap="tests/bootstrap.php"
+<phpunit bootstrap="vendor/autoload.php"
          colors="true"
          convertErrorsToExceptions="true"
          convertNoticesToExceptions="true"
diff --git a/tests/AllTest.php b/tests/AllTest.php
index 1cc363f..96be183 100644
--- a/tests/AllTest.php
+++ b/tests/AllTest.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace React\Tests\Promise\Stream;
+
 use React\Promise\Stream;
 use React\Stream\ThroughStream;
 
diff --git a/tests/BufferTest.php b/tests/BufferTest.php
index 3f46a76..970ee99 100644
--- a/tests/BufferTest.php
+++ b/tests/BufferTest.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace React\Tests\Promise\Stream;
+
 use Clue\React\Block;
 use React\EventLoop\Factory;
 use React\Promise\Stream;
diff --git a/tests/CallableStub.php b/tests/CallableStub.php
new file mode 100644
index 0000000..f398c04
--- /dev/null
+++ b/tests/CallableStub.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace React\Tests\Promise\Stream;
+
+class CallableStub
+{
+    public function __invoke()
+    {
+    }
+}
diff --git a/tests/FirstTest.php b/tests/FirstTest.php
index 31b728b..04eb7c8 100644
--- a/tests/FirstTest.php
+++ b/tests/FirstTest.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace React\Tests\Promise\Stream;
+
 use React\Promise\Stream;
 use React\Stream\ThroughStream;
 
diff --git a/tests/bootstrap.php b/tests/TestCase.php
similarity index 90%
rename from tests/bootstrap.php
rename to tests/TestCase.php
index b1bcde9..842b94b 100644
--- a/tests/bootstrap.php
+++ b/tests/TestCase.php
@@ -1,8 +1,8 @@
 <?php
 
-require_once __DIR__ . '/../vendor/autoload.php';
+namespace React\Tests\Promise\Stream;
 
-class TestCase extends PHPUnit_Framework_TestCase
+class TestCase extends \PHPUnit_Framework_TestCase
 {
     protected function expectCallableOnce()
     {
@@ -51,7 +51,7 @@ protected function expectCallableNever()
      */
     protected function createCallableMock()
     {
-        return $this->getMock('CallableStub');
+        return $this->getMock('React\Tests\Promise\Stream\CallableStub');
     }
 
     protected function expectPromiseResolve($promise)
@@ -81,11 +81,3 @@ protected function expectPromiseReject($promise)
         return $promise;
     }
 }
-
-class CallableStub
-{
-    public function __invoke()
-    {
-    }
-}
-
diff --git a/tests/UnwrapReadableTest.php b/tests/UnwrapReadableTest.php
index a5b5268..75eb0ac 100644
--- a/tests/UnwrapReadableTest.php
+++ b/tests/UnwrapReadableTest.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace React\Tests\Promise\Stream;
+
 use Clue\React\Block;
 use React\EventLoop\Factory;
 use React\Promise;
diff --git a/tests/UnwrapWritableTest.php b/tests/UnwrapWritableTest.php
index 5a8d093..8a6d384 100644
--- a/tests/UnwrapWritableTest.php
+++ b/tests/UnwrapWritableTest.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace React\Tests\Promise\Stream;
+
 use Clue\React\Block;
 use React\EventLoop\Factory;
 use React\Promise;