diff --git a/composer.json b/composer.json
index da785746..6b438d95 100644
--- a/composer.json
+++ b/composer.json
@@ -12,9 +12,6 @@
 	"require": {
 		"php": "~7.1",
 		"phpstan/phpstan": "^0.10",
-		"doctrine/common": "^2.7",
-		"doctrine/orm": "^2.5",
-		"doctrine/collections": "^1.0",
 		"nikic/php-parser": "^4.0"
 	},
 	"require-dev": {
@@ -25,7 +22,15 @@
 		"phpstan/phpstan-phpunit": "^0.10",
 		"phpstan/phpstan-strict-rules": "^0.10",
 		"phpunit/phpunit": "^7.0",
-		"slevomat/coding-standard": "^4.5.2"
+		"slevomat/coding-standard": "^4.5.2",
+		"doctrine/common": "^2.7",
+		"doctrine/orm": "^2.5",
+		"doctrine/collections": "^1.0"
+	},
+	"conflict": {
+		"doctrine/common": "<2.7",
+		"doctrine/orm": "<2.5",
+		"doctrine/collections": "<1.0"
 	},
 	"autoload": {
 		"psr-4": {
diff --git a/src/Reflection/Doctrine/DoctrineSelectableClassReflectionExtension.php b/src/Reflection/Doctrine/DoctrineSelectableClassReflectionExtension.php
index df79842f..a74c5244 100644
--- a/src/Reflection/Doctrine/DoctrineSelectableClassReflectionExtension.php
+++ b/src/Reflection/Doctrine/DoctrineSelectableClassReflectionExtension.php
@@ -2,7 +2,7 @@
 
 namespace PHPStan\Reflection\Doctrine;
 
-class DoctrineSelectableClassReflectionExtension implements \PHPStan\Reflection\MethodsClassReflectionExtension, \PHPStan\Reflection\BrokerAwareClassReflectionExtension
+class DoctrineSelectableClassReflectionExtension implements \PHPStan\Reflection\MethodsClassReflectionExtension, \PHPStan\Reflection\BrokerAwareExtension
 {
 
 	/** @var \PHPStan\Broker\Broker */
@@ -15,13 +15,13 @@ public function setBroker(\PHPStan\Broker\Broker $broker): void
 
 	public function hasMethod(\PHPStan\Reflection\ClassReflection $classReflection, string $methodName): bool
 	{
-		return $classReflection->getName() === \Doctrine\Common\Collections\Collection::class
+		return $classReflection->getName() === 'Doctrine\Common\Collections\Collection'
 			&& $methodName === 'matching';
 	}
 
 	public function getMethod(\PHPStan\Reflection\ClassReflection $classReflection, string $methodName): \PHPStan\Reflection\MethodReflection
 	{
-		$selectableReflection = $this->broker->getClass(\Doctrine\Common\Collections\Selectable::class);
+		$selectableReflection = $this->broker->getClass('Doctrine\Common\Collections\Selectable');
 		return $selectableReflection->getNativeMethod($methodName);
 	}
 
diff --git a/src/Type/Doctrine/DoctrineSelectableDynamicReturnTypeExtension.php b/src/Type/Doctrine/DoctrineSelectableDynamicReturnTypeExtension.php
index d5801999..b03bb579 100644
--- a/src/Type/Doctrine/DoctrineSelectableDynamicReturnTypeExtension.php
+++ b/src/Type/Doctrine/DoctrineSelectableDynamicReturnTypeExtension.php
@@ -12,7 +12,7 @@ class DoctrineSelectableDynamicReturnTypeExtension implements \PHPStan\Type\Dyna
 
 	public function getClass(): string
 	{
-		return \Doctrine\Common\Collections\Collection::class;
+		return 'Doctrine\Common\Collections\Collection';
 	}
 
 	public function isMethodSupported(MethodReflection $methodReflection): bool
diff --git a/src/Type/Doctrine/EntityManagerFindDynamicReturnTypeExtension.php b/src/Type/Doctrine/EntityManagerFindDynamicReturnTypeExtension.php
index 8c252b7c..2498cc8d 100644
--- a/src/Type/Doctrine/EntityManagerFindDynamicReturnTypeExtension.php
+++ b/src/Type/Doctrine/EntityManagerFindDynamicReturnTypeExtension.php
@@ -16,7 +16,7 @@ class EntityManagerFindDynamicReturnTypeExtension implements \PHPStan\Type\Dynam
 
 	public function getClass(): string
 	{
-		return \Doctrine\Common\Persistence\ObjectManager::class;
+		return 'Doctrine\Common\Persistence\ObjectManager';
 	}
 
 	public function isMethodSupported(MethodReflection $methodReflection): bool
diff --git a/src/Type/Doctrine/EntityManagerGetRepositoryDynamicReturnTypeExtension.php b/src/Type/Doctrine/EntityManagerGetRepositoryDynamicReturnTypeExtension.php
index 8298c0f6..b383c18f 100644
--- a/src/Type/Doctrine/EntityManagerGetRepositoryDynamicReturnTypeExtension.php
+++ b/src/Type/Doctrine/EntityManagerGetRepositoryDynamicReturnTypeExtension.php
@@ -23,7 +23,7 @@ public function __construct(string $repositoryClass)
 
 	public function getClass(): string
 	{
-		return \Doctrine\Common\Persistence\ObjectManager::class;
+		return 'Doctrine\Common\Persistence\ObjectManager';
 	}
 
 	public function isMethodSupported(MethodReflection $methodReflection): bool
diff --git a/src/Type/Doctrine/EntityRepositoryDynamicReturnTypeExtension.php b/src/Type/Doctrine/EntityRepositoryDynamicReturnTypeExtension.php
index d96afc95..b542508c 100644
--- a/src/Type/Doctrine/EntityRepositoryDynamicReturnTypeExtension.php
+++ b/src/Type/Doctrine/EntityRepositoryDynamicReturnTypeExtension.php
@@ -17,7 +17,7 @@ class EntityRepositoryDynamicReturnTypeExtension implements \PHPStan\Type\Dynami
 
 	public function getClass(): string
 	{
-		return \Doctrine\ORM\EntityRepository::class;
+		return 'Doctrine\ORM\EntityRepository';
 	}
 
 	public function isMethodSupported(MethodReflection $methodReflection): bool
diff --git a/src/Type/Doctrine/ObjectManagerMergeDynamicReturnTypeExtension.php b/src/Type/Doctrine/ObjectManagerMergeDynamicReturnTypeExtension.php
index 9fbeef51..55651d28 100644
--- a/src/Type/Doctrine/ObjectManagerMergeDynamicReturnTypeExtension.php
+++ b/src/Type/Doctrine/ObjectManagerMergeDynamicReturnTypeExtension.php
@@ -13,7 +13,7 @@ class ObjectManagerMergeDynamicReturnTypeExtension implements \PHPStan\Type\Dyna
 
 	public function getClass(): string
 	{
-		return \Doctrine\Common\Persistence\ObjectManager::class;
+		return 'Doctrine\Common\Persistence\ObjectManager';
 	}
 
 	public function isMethodSupported(MethodReflection $methodReflection): bool