diff --git a/src/Plugin.php b/src/Plugin.php
index ff501dd..7cde4b2 100644
--- a/src/Plugin.php
+++ b/src/Plugin.php
@@ -2,6 +2,7 @@
 
 namespace Phabel;
 
+use Phabel\PluginGraph\PackageContext;
 use PhpParser\Node;
 use PhpParser\Node\Arg;
 use PhpParser\Node\Expr;
@@ -20,6 +21,10 @@ abstract class Plugin implements PluginInterface
      * Configuration array.
      */
     private array $config = [];
+    /**
+     * Package context
+     */
+    private PackageContext $ctx;
     /**
      * Set configuration array.
      *
@@ -30,6 +35,48 @@ abstract class Plugin implements PluginInterface
     {
         $this->config = $config;
     }
+    /**
+     * Set package context
+     *
+     * @param PackageContext $ctx Ctx
+     * 
+     * @return void
+     */
+    public function setPackageContext(PackageContext $ctx): void
+    {
+        $this->ctx = $ctx;
+    }
+    /**
+     * Get package context
+     *
+     * @return PackageContext
+     */
+    public function getPackageContext(): PackageContext
+    {
+        return $this->ctx;
+    }
+    /**
+     * Check if plugin should run
+     *
+     * @param string $package Package name
+     * 
+     * @return boolean
+     */
+    public function shouldRun(string $package): bool
+    {
+        return $this->ctx->has($package);
+    }
+    /**
+     * Check if plugin should run
+     *
+     * @param string $file File name
+     * 
+     * @return boolean
+     */
+    public function shouldRunFile(string $file): bool
+    {
+        return true;
+    }
     /**
      * Replace node of one type with another.
      *
diff --git a/src/Plugin/Memoization.php b/src/Plugin/Memoization.php
index 5527399..2f03f0b 100644
--- a/src/Plugin/Memoization.php
+++ b/src/Plugin/Memoization.php
@@ -122,7 +122,7 @@ class Memoization
     public function leaveFunctionLike(FunctionLike $fun): void
     {
         $this->cache->pop();
-        \array_unshift($fun->stmts, $this->stmts->pop());
+        $fun->stmts = \array_merge($this->stmts->pop(), $fun->stmts);
     }
 
     /**
diff --git a/src/PluginGraph/GraphInternal.php b/src/PluginGraph/GraphInternal.php
index a26dc06..fa2675d 100644
--- a/src/PluginGraph/GraphInternal.php
+++ b/src/PluginGraph/GraphInternal.php
@@ -59,12 +59,6 @@ class GraphInternal
      */
     public function addPlugin(string $plugin, array $config, PackageContext $ctx): array
     {
-        if ($config === ['*']) {
-            if (isset($this->plugins[$plugin])) {
-                return \array_map(fn (Node $node) => $node->addPackageContext($ctx), $this->plugins[$plugin]);
-            }
-            $config = [];
-        }
         $configs = $plugin::splitConfig($config);
         $nodes = [];
         foreach ($configs as $config) {
@@ -87,11 +81,11 @@ class GraphInternal
     {
         $configStr = \var_export($config, true);
         if (isset($this->plugins[$plugin][$configStr])) {
-            return $this->plugins[$plugin][$configStr]->addPackageContext($ctx);
+            return $this->plugins[$plugin][$configStr];
         }
-        $this->plugins[$plugin][$configStr] = $node = new Node($this);
+        $this->plugins[$plugin][$configStr] = $node = new Node($this, $ctx);
         $this->unlinkedNodes->attach($node);
-        return $node->init($plugin, $config, $ctx);
+        return $node->init($plugin, $config);
     }
 
     /**
@@ -115,6 +109,7 @@ class GraphInternal
     public function flatten(): \SplQueue
     {
         if (!$this->plugins) {
+            /** @var SplQueue<SplQueue<Plugin>> */
             return new \SplQueue;
         }
         if ($this->unlinkedNodes->count()) {
diff --git a/src/PluginGraph/Node.php b/src/PluginGraph/Node.php
index 1f5d07a..fff1ceb 100644
--- a/src/PluginGraph/Node.php
+++ b/src/PluginGraph/Node.php
@@ -27,11 +27,11 @@ class Node
     private string $name;
 
     /**
-     * Associated package contexts.
+     * Associated package context.
      *
-     * @var SplObjectStorage<PackageContext, void>
+     * @var PackageContext
      */
-    private SplObjectStorage $packageContexts;
+    private PackageContext $packageContext;
     /**
      * Nodes that this node requires.
      *
@@ -80,10 +80,10 @@ class Node
      *
      * @param GraphInternal  $graph  Graph instance
      */
-    public function __construct(GraphInternal $graph)
+    public function __construct(GraphInternal $graph, PackageContext $ctx)
     {
+        $this->packageContext = $ctx;
         $this->graph = $graph;
-        $this->packageContexts = new SplObjectStorage;
         $this->requiredBy = new SplObjectStorage;
         $this->extendedBy = new SplObjectStorage;
         $this->requires = new SplObjectStorage;
@@ -100,30 +100,29 @@ class Node
      *
      * @return self
      */
-    public function init(string $plugin, array $config, PackageContext $ctx): self
+    public function init(string $plugin, array $config): self
     {
         $this->name = $plugin;
         $this->plugin = new Plugins($plugin, $config);
-        $this->packageContexts->attach($ctx);
 
         $this->canBeRequired = PluginCache::canBeRequired($plugin);
         foreach (PluginCache::runAfter($plugin) as $class => $config) {
-            foreach ($this->graph->addPlugin($class, $config, $ctx) as $node) {
+            foreach ($this->graph->addPlugin($class, $config, $this->packageContext) as $node) {
                 $this->require($node);
             }
         }
         foreach (PluginCache::runBefore($plugin) as $class => $config) {
-            foreach ($this->graph->addPlugin($class, $config, $ctx) as $node) {
+            foreach ($this->graph->addPlugin($class, $config, $this->packageContext) as $node) {
                 $node->require($this);
             }
         }
         foreach (PluginCache::runWithAfter($plugin) as $class => $config) {
-            foreach ($this->graph->addPlugin($class, $config, $ctx) as $node) {
+            foreach ($this->graph->addPlugin($class, $config, $this->packageContext) as $node) {
                 $this->extend($node);
             }
         }
         foreach (PluginCache::runWithBefore($plugin) as $class => $config) {
-            foreach ($this->graph->addPlugin($class, $config, $ctx) as $node) {
+            foreach ($this->graph->addPlugin($class, $config, $this->packageContext) as $node) {
                 $node->extend($this);
             }
         }
@@ -171,28 +170,6 @@ class Node
         $this->graph->linkNode($this);
     }
 
-    /**
-     * Add package context.
-     *
-     * @param PackageContext $ctx Context
-     *
-     * @return self
-     */
-    public function addPackageContext(PackageContext $ctx): self
-    {
-        if ($this->packageContexts->contains($ctx)) {
-            return $this;
-        }
-        $this->packageContexts->attach($ctx);
-        foreach ($this->requires as $node) {
-            $node->addPackageContext($ctx);
-        }
-        foreach ($this->extends as $node) {
-            $node->addPackageContext($ctx);
-        }
-        return $this;
-    }
-
     /**
      * Merge node with another node.
      *
@@ -202,6 +179,7 @@ class Node
      */
     public function merge(self $other): Node
     {
+        $this->packageContext->merge($other->packageContext);
         $this->plugin->merge($other->plugin);
         foreach ($other->requiredBy as $node) {
             $node->require($this);
@@ -234,7 +212,7 @@ class Node
         return $queue;
     }
     /**
-     * Look for circular references.
+     * Look for circular references, while merging package contexts.
      *
      * @return self
      */
@@ -253,10 +231,10 @@ class Node
         $this->visitedCircular = true;
 
         foreach ($this->requiredBy as $node) {
-            $node->circular();
+            $this->packageContext->merge($node->circular()->packageContext);
         }
         foreach ($this->extendedBy as $node) {
-            $node->circular();
+            $this->packageContext->merge($node->circular()->packageContext);
         }
 
         $this->visitedCircular = false;
@@ -273,7 +251,7 @@ class Node
     private function flattenInternal(SplQueue $splQueue): void
     {
         $queue = $splQueue->top();
-        $this->plugin->enqueue($queue);
+        $this->plugin->enqueue($queue, $this->packageContext);
 
         /** @var SplQueue<Node> */
         $extendedBy = new SplQueue;
@@ -309,6 +287,8 @@ class Node
             $requiredBy->enqueue($prevNode);
         }
 
+
+        
         foreach ($extendedBy as $node) {
             $node->extends->detach($this);
             if (\count($node->extends) + \count($node->requires) === 0) {
diff --git a/src/PluginGraph/PackageContext.php b/src/PluginGraph/PackageContext.php
index 2255dd6..e7d2b02 100644
--- a/src/PluginGraph/PackageContext.php
+++ b/src/PluginGraph/PackageContext.php
@@ -37,6 +37,18 @@ class PackageContext
         return $this;
     }
 
+    /**
+     * Check if a package is present in the package context
+     *
+     * @param string $package Package
+     * 
+     * @return boolean
+     */
+    public function has(string $package): bool
+    {
+        return isset($this->packages[$package]);
+    }
+
     /**
      * Get package list.
      *
diff --git a/src/PluginGraph/Plugins.php b/src/PluginGraph/Plugins.php
index e368efc..ab37534 100644
--- a/src/PluginGraph/Plugins.php
+++ b/src/PluginGraph/Plugins.php
@@ -53,12 +53,13 @@ class Plugins
      *
      * @return void
      */
-    public function enqueue(SplQueue $queue): void
+    public function enqueue(SplQueue $queue, PackageContext $ctx): void
     {
         foreach ($this->plugins as $plugin => $configs) {
             foreach ($plugin::mergeConfigs(...$configs) as $config) {
                 $pluginObj = new $plugin;
                 $pluginObj->setConfigArray($config);
+                $pluginObj->setPackageContext($ctx);
                 $queue->enqueue($pluginObj);
             }
         }
diff --git a/src/PluginInterface.php b/src/PluginInterface.php
index d889656..6451236 100644
--- a/src/PluginInterface.php
+++ b/src/PluginInterface.php
@@ -2,6 +2,8 @@
 
 namespace Phabel;
 
+use Phabel\PluginGraph\PackageContext;
+
 interface PluginInterface
 {
     /**
@@ -59,6 +61,36 @@ interface PluginInterface
      * @return void
      */
     public function setConfigArray(array $config): void;
+    /**
+     * Set package context
+     *
+     * @param PackageContext $ctx Ctx
+     * 
+     * @return void
+     */
+    public function setPackageContext(PackageContext $ctx): void;
+    /**
+     * Get package context
+     *
+     * @return PackageContext
+     */
+    public function getPackageContext(): PackageContext;
+    /**
+     * Check if plugin should run
+     *
+     * @param string $package Package name
+     * 
+     * @return boolean
+     */
+    public function shouldRun(string $package): bool;
+    /**
+     * Check if plugin should run
+     *
+     * @param string $file File name
+     * 
+     * @return boolean
+     */
+    public function shouldRunFile(string $file): bool;
     /**
      * Get configuration key.
      *