diff --git a/composer.json b/composer.json
index f16a3dbb2..981f96afe 100644
--- a/composer.json
+++ b/composer.json
@@ -86,11 +86,5 @@
     "support": {
         "issues": "https://github.com/composer/composer/issues",
         "irc": "irc://irc.freenode.org/composer"
-    },
-    "repositories": [
-        {
-            "type": "vcs",
-            "url": "git@github.com:Seldaek/semver.git"
-        }
-    ]
+    }
 }
diff --git a/composer.lock b/composer.lock
index 1f7e0e7f0..aa50c62df 100644
--- a/composer.lock
+++ b/composer.lock
@@ -109,16 +109,7 @@
                     "Composer\\Semver\\": "src"
                 }
             },
-            "autoload-dev": {
-                "psr-4": {
-                    "Composer\\Semver\\": "tests"
-                }
-            },
-            "scripts": {
-                "test": [
-                    "phpunit"
-                ]
-            },
+            "notification-url": "https://packagist.org/downloads/",
             "license": [
                 "MIT"
             ],
@@ -450,7 +441,17 @@
             "license": [
                 "MIT"
             ],
+            "authors": [
+                {
+                    "name": "Jan Sorgalla",
+                    "email": "jsorgalla@gmail.com"
+                }
+            ],
             "description": "A lightweight implementation of CommonJS Promises/A for PHP",
+            "support": {
+                "issues": "https://github.com/reactphp/promise/issues",
+                "source": "https://github.com/reactphp/promise/tree/1.0"
+            },
             "time": "2016-03-07T13:46:50+00:00"
         },
         {
@@ -500,6 +501,10 @@
                 "parser",
                 "validator"
             ],
+            "support": {
+                "issues": "https://github.com/Seldaek/jsonlint/issues",
+                "source": "https://github.com/Seldaek/jsonlint/tree/master"
+            },
             "funding": [
                 {
                     "url": "https://github.com/Seldaek",
@@ -1046,6 +1051,10 @@
                 "constructor",
                 "instantiate"
             ],
+            "support": {
+                "issues": "https://github.com/doctrine/instantiator/issues",
+                "source": "https://github.com/doctrine/instantiator/tree/master"
+            },
             "time": "2015-06-14T21:17:01+00:00"
         },
         {
@@ -1095,6 +1104,10 @@
                     "email": "mike.vanriel@naenius.com"
                 }
             ],
+            "support": {
+                "issues": "https://github.com/phpDocumentor/ReflectionDocBlock/issues",
+                "source": "https://github.com/phpDocumentor/ReflectionDocBlock/tree/release/2.x"
+            },
             "time": "2016-01-25T08:17:30+00:00"
         },
         {
@@ -1226,6 +1239,10 @@
                 "compare",
                 "equality"
             ],
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/comparator/issues",
+                "source": "https://github.com/sebastianbergmann/comparator/tree/1.2"
+            },
             "time": "2017-01-29T09:50:25+00:00"
         },
         {
@@ -1278,6 +1295,10 @@
             "keywords": [
                 "diff"
             ],
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/diff/issues",
+                "source": "https://github.com/sebastianbergmann/diff/tree/1.4"
+            },
             "time": "2017-05-22T07:24:03+00:00"
         },
         {
@@ -1489,5 +1510,5 @@
     "platform-overrides": {
         "php": "5.3.9"
     },
-    "plugin-api-version": "1.1.0"
+    "plugin-api-version": "2.0.0"
 }
diff --git a/src/Composer/DependencyResolver/PoolBuilder.php b/src/Composer/DependencyResolver/PoolBuilder.php
index f680dd710..8b602b1aa 100644
--- a/src/Composer/DependencyResolver/PoolBuilder.php
+++ b/src/Composer/DependencyResolver/PoolBuilder.php
@@ -125,13 +125,13 @@ class PoolBuilder
         }
 
         foreach ($request->getFixedPackages() as $package) {
-            // using EmptyConstraint here because fixed packages do not need to retrigger
+            // using MatchAllConstraint here because fixed packages do not need to retrigger
             // loading any packages
-            $this->loadedPackages[$package->getName()] = new EmptyConstraint();
+            $this->loadedPackages[$package->getName()] = new MatchAllConstraint();
 
             // replace means conflict, so if a fixed package replaces a name, no need to load that one, packages would conflict anyways
             foreach ($package->getReplaces() as $link) {
-                $this->loadedPackages[$link->getTarget()] = new EmptyConstraint();
+                $this->loadedPackages[$link->getTarget()] = new MatchAllConstraint();
             }
 
             // TODO in how far can we do the above for conflicts? It's more tricky cause conflicts can be limited to