diff --git a/composer.lock b/composer.lock
index e492eb8..f9595d5 100644
--- a/composer.lock
+++ b/composer.lock
@@ -1,28 +1,31 @@
 {
     "_readme": [
         "This file locks the dependencies of your project to a known state",
-        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
     "content-hash": "9c1d5fe646ae51f51c3a0d300df81a1d",
     "packages": [
         {
             "name": "react/promise",
-            "version": "v2.5.0",
+            "version": "v2.7.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/reactphp/promise.git",
-                "reference": "2760f3898b7e931aa71153852dcd48a75c9b95db"
+                "reference": "f4edc2581617431aea50430749db55cc3fc031b3"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/reactphp/promise/zipball/2760f3898b7e931aa71153852dcd48a75c9b95db",
-                "reference": "2760f3898b7e931aa71153852dcd48a75c9b95db",
+                "url": "https://api.github.com/repos/reactphp/promise/zipball/f4edc2581617431aea50430749db55cc3fc031b3",
+                "reference": "f4edc2581617431aea50430749db55cc3fc031b3",
                 "shasum": ""
             },
             "require": {
                 "php": ">=5.4.0"
             },
+            "require-dev": {
+                "phpunit/phpunit": "~4.8"
+            },
             "type": "library",
             "autoload": {
                 "psr-4": {
@@ -47,7 +50,7 @@
                 "promise",
                 "promises"
             ],
-            "time": "2016-12-22T14:09:01+00:00"
+            "time": "2018-06-13T15:59:06+00:00"
         },
         {
             "name": "reactivex/rxphp",