diff --git a/composer.json b/composer.json
index 9b9f11d..0d18eb1 100644
--- a/composer.json
+++ b/composer.json
@@ -4,7 +4,7 @@
     "type": "psalm-plugin",
     "require": {
         "barryvdh/laravel-ide-helper": "^2.6",
-        "vimeo/psalm": "^3.7",
+        "vimeo/psalm": "^3.8.2",
         "orchestra/testbench": "^3.5 || ^4.0"
     },
     "license": "MIT",
diff --git a/src/AbstractPlugin.php b/src/AbstractPlugin.php
index 5771ac2..f7ead5d 100644
--- a/src/AbstractPlugin.php
+++ b/src/AbstractPlugin.php
@@ -14,7 +14,7 @@ abstract class AbstractPlugin implements PluginEntryPointInterface
 {
     use CreatesApplication;
 
-    /** @var array<class-string> */
+    /** @var array<string> */
     public static $model_classes = [];
 
     /**
@@ -76,7 +76,7 @@ abstract class AbstractPlugin implements PluginEntryPointInterface
         \Illuminate\Filesystem\Filesystem $fake_filesystem,
         $view_factory,
         string $cache_dir
-    ) {
+    ) : void {
         $stubs_generator_command = new \Barryvdh\LaravelIdeHelper\Console\GeneratorCommand(
             $app['config'],
             $fake_filesystem,
diff --git a/src/AppInterfaceProvider.php b/src/AppInterfaceProvider.php
index 0051597..0b27e1b 100644
--- a/src/AppInterfaceProvider.php
+++ b/src/AppInterfaceProvider.php
@@ -14,6 +14,7 @@ class AppInterfaceProvider implements
     \Psalm\Plugin\Hook\MethodVisibilityProviderInterface,
     \Psalm\Plugin\Hook\MethodParamsProviderInterface
 {
+    /** @return array<string> */
     public static function getClassLikeNames() : array
     {
         return [
diff --git a/src/FakeFilesystem.php b/src/FakeFilesystem.php
index abaf8d0..bca2ef3 100644
--- a/src/FakeFilesystem.php
+++ b/src/FakeFilesystem.php
@@ -13,7 +13,7 @@ class FakeFilesystem extends \Illuminate\Filesystem\Filesystem
      * @param  string  $path
      * @param  string  $contents
      * @param  bool  $lock
-     * @return int
+     * @return bool|int
      */
     public function put($path, $contents, $lock = false)
     {
diff --git a/src/FakeMetaCommand.php b/src/FakeMetaCommand.php
index 2c8a83f..1054f93 100644
--- a/src/FakeMetaCommand.php
+++ b/src/FakeMetaCommand.php
@@ -7,7 +7,7 @@ class FakeMetaCommand extends \Barryvdh\LaravelIdeHelper\Console\MetaCommand
      * @return void
      */
     protected function registerClassAutoloadExceptions() {
-        spl_autoload_register(function ($class) {
+        spl_autoload_register(function (string $class) {
             throw new \ReflectionException("Class '$class' not found.");
         });
     }
diff --git a/src/PropertyProvider/ModelPropertyProvider.php b/src/PropertyProvider/ModelPropertyProvider.php
index 8646e65..679c782 100644
--- a/src/PropertyProvider/ModelPropertyProvider.php
+++ b/src/PropertyProvider/ModelPropertyProvider.php
@@ -13,6 +13,7 @@ class ModelPropertyProvider
         \Psalm\Plugin\Hook\PropertyVisibilityProviderInterface,
         \Psalm\Plugin\Hook\PropertyTypeProviderInterface
 {
+    /** @return array<string, string> */
     public static function getClassLikeNames() : array
     {
         return \Psalm\LaravelPlugin\AbstractPlugin::$model_classes;
diff --git a/src/SchemaAggregator.php b/src/SchemaAggregator.php
index e3004b0..7ffeba5 100644
--- a/src/SchemaAggregator.php
+++ b/src/SchemaAggregator.php
@@ -28,6 +28,7 @@ class SchemaAggregator
         foreach ($stmts as $stmt) {
             if ($stmt instanceof PhpParser\Node\Stmt\ClassMethod
                 && $stmt->name->name === 'up'
+                && $stmt->stmts
             ) {
                 $this->addUpMethodStatements($stmt->stmts);
             }
@@ -94,9 +95,13 @@ class SchemaAggregator
 
         $update_closure = $call->args[1]->value;
 
-        $call_arg_name = $call->args[1]->value->params[0]->var->name;
+        if ($call->args[1]->value->params[0]->var instanceof PhpParser\Node\Expr\Variable
+            && is_string($call->args[1]->value->params[0]->var->name)
+        ) {
+            $call_arg_name = $call->args[1]->value->params[0]->var->name;
 
-        $this->processColumnUpdates($table_name, $call_arg_name, $update_closure->stmts);
+            $this->processColumnUpdates($table_name, $call_arg_name, $update_closure->stmts);
+        }   
     }
 
     private function dropTable(PhpParser\Node\Expr\StaticCall $call) : void
@@ -172,6 +177,7 @@ class SchemaAggregator
 
                 if ($root_var instanceof PhpParser\Node\Expr\Variable
                     && $root_var->name === $call_arg_name
+                    && $first_method_call->name instanceof PhpParser\Node\Identifier
                 ) {
                     $first_arg = $first_method_call->args[0]->value ?? null;
                     $second_arg = $first_method_call->args[1]->value ?? null;
@@ -234,7 +240,7 @@ class SchemaAggregator
                         $second_arg_array = [];
 
                         foreach ($second_arg->items as $array_item) {
-                            if ($array_item->value instanceof PhpParser\Node\Scalar\String_) {
+                            if ($array_item && $array_item->value instanceof PhpParser\Node\Scalar\String_) {
                                 $second_arg_array[] = $array_item->value->value;
                             }
                         }