diff --git a/tests/LibeventReactorProcessTest.php b/tests/LibeventReactorProcessTest.php
index 88a50f3..1a2ec04 100644
--- a/tests/LibeventReactorProcessTest.php
+++ b/tests/LibeventReactorProcessTest.php
@@ -6,8 +6,14 @@ use Amp\LibeventReactor;
 
 class LibeventReactorProcessTest extends AbstractProcessTest {
 
-    public function setUp(){
-        \Amp\reactor(new LibeventReactor());
+    protected function setUp() {
+        if (extension_loaded("libevent")) {
+            \Amp\reactor($assign = new LibeventReactor);
+        } else {
+            $this->markTestSkipped(
+                "libevent extension not loaded"
+            );
+        }
     }
 
     public function testReactor() {
diff --git a/tests/UvReactorProcessTest.php b/tests/UvReactorProcessTest.php
index 3e71cb0..fed1be9 100644
--- a/tests/UvReactorProcessTest.php
+++ b/tests/UvReactorProcessTest.php
@@ -7,7 +7,13 @@ use Amp\UvReactor;
 class UvReactorProcessTest extends AbstractProcessTest {
 
     public function setUp(){
-        \Amp\reactor(new UvReactor());
+        if (extension_loaded("uv")) {
+            \Amp\reactor($assign = new UvReactor);
+        } else {
+            $this->markTestSkipped(
+                "php-uv extension not loaded"
+            );
+        }
     }
 
     public function testReactor() {