diff --git a/src/Type/ContainerDynamicReturnTypeExtension.php b/src/Type/ContainerDynamicReturnTypeExtension.php
index 3a071ed7..ad3aa26d 100644
--- a/src/Type/ContainerDynamicReturnTypeExtension.php
+++ b/src/Type/ContainerDynamicReturnTypeExtension.php
@@ -67,6 +67,12 @@ public function getTypeFromMethodCall(
                 }
             }
 
+            // A dynamic service ID has no constant strings; unioning zero
+            // types would produce `never`.
+            if ($types === []) {
+                return $returnType;
+            }
+
             return TypeCombinator::union(...$types);
         } elseif ($methodName === 'get') {
             $args = $methodCall->getArgs();
@@ -89,12 +95,20 @@ public function getTypeFromMethodCall(
 
             $argType = $scope->getType($args[0]->value);
 
-            foreach ($argType->getConstantStrings() as $constantStringType) {
+            $constantStrings = $argType->getConstantStrings();
+            foreach ($constantStrings as $constantStringType) {
                 $serviceId = $constantStringType->getValue();
                 $service = $this->serviceMap->getService($serviceId);
                 $types[] = $service !== null ? $service->getType() : $returnType;
             }
 
+            // A dynamic service ID has no constant strings; fall back to the
+            // declared return type so the union cannot collapse to `never`,
+            // while keeping any null added for NULL_ON_INVALID_REFERENCE.
+            if ($constantStrings === []) {
+                $types[] = $returnType;
+            }
+
             return TypeCombinator::union(...$types);
         }
 
diff --git a/tests/src/Rules/EntityStoragePropertyAssignmentRuleTest.php b/tests/src/Rules/EntityStoragePropertyAssignmentRuleTest.php
index 451afb5f..aba4ea6f 100644
--- a/tests/src/Rules/EntityStoragePropertyAssignmentRuleTest.php
+++ b/tests/src/Rules/EntityStoragePropertyAssignmentRuleTest.php
@@ -44,4 +44,9 @@ public function testRule(): void
             ]
         );
     }
+
+    public function testBug1012(): void
+    {
+        $this->analyse([__DIR__ . '/data/bug-1012-proxy.php'], []);
+    }
 }
diff --git a/tests/src/Rules/data/bug-1012-proxy.php b/tests/src/Rules/data/bug-1012-proxy.php
new file mode 100644
index 00000000..e30634ef
--- /dev/null
+++ b/tests/src/Rules/data/bug-1012-proxy.php
@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace mglaman\PHPStanDrupal\Tests\Rules\data;
+
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+// No error: core-generated proxy classes fetch the decorated service with a
+// dynamic service ID (issue #1012).
+class GeneratedProxyLazyLoadingService
+{
+    protected ContainerInterface $container;
+
+    protected string $drupalProxyOriginalServiceId;
+
+    protected object $service;
+
+    public function __construct(ContainerInterface $container, string $drupal_proxy_original_service_id)
+    {
+        $this->container = $container;
+        $this->drupalProxyOriginalServiceId = $drupal_proxy_original_service_id;
+    }
+
+    protected function lazyLoadItself(): object
+    {
+        if (!isset($this->service)) {
+            $this->service = $this->container->get($this->drupalProxyOriginalServiceId);
+        }
+
+        return $this->service;
+    }
+}
diff --git a/tests/src/Type/DrupalContainerDynamicReturnTypeTest.php b/tests/src/Type/DrupalContainerDynamicReturnTypeTest.php
index 10e29aa6..73db87ce 100644
--- a/tests/src/Type/DrupalContainerDynamicReturnTypeTest.php
+++ b/tests/src/Type/DrupalContainerDynamicReturnTypeTest.php
@@ -17,6 +17,7 @@ public static function dataFileAsserts(): iterable
         yield from self::gatherAssertTypes(__DIR__ . '/data/drupal-service-static.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/drupal-class-resolver.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/bug-563.php');
+        yield from self::gatherAssertTypes(__DIR__ . '/data/bug-1012.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/container-optional.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/synthetic.php');
     }
diff --git a/tests/src/Type/data/bug-1012.php b/tests/src/Type/data/bug-1012.php
new file mode 100644
index 00000000..474252b5
--- /dev/null
+++ b/tests/src/Type/data/bug-1012.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace Bug1012;
+
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use function PHPStan\Testing\assertType;
+
+function foo(string $service_id): void {
+    $container = \Drupal::getContainer();
+    assert($container !== null);
+
+    assertType('object', $container->get($service_id));
+    assertType('object|null', $container->get($service_id, ContainerInterface::NULL_ON_INVALID_REFERENCE));
+    assertType('bool', $container->has($service_id));
+}