diff --git a/composer.json b/composer.json
index 6d6cec5..ada73ac 100644
--- a/composer.json
+++ b/composer.json
@@ -3,24 +3,20 @@
     "name": "pre/deferred",
     "license": "MIT",
     "require": {
-        "pre/plugin": "^0.7.3"
+        "pre/plugin": "^0.10.0"
     },
     "autoload": {
         "psr-4": {
-            "Pre\\Deferred\\": "src"
+            "Pre\\Deferred\\": "source"
         }
     },
     "require-dev": {
         "phpunit/phpunit": "^5.0|^6.0"
     },
     "autoload-dev": {
-        "psr-4": {
-            "Pre\\Deferred\\": "tests"
-        }
+        "files": ["tests/stubs.php"]
     },
     "extra": {
-        "macros": [
-            "src/macros.yay"
-        ]
+        "macros": ["source/macros.yay"]
     }
 }
diff --git a/phpunit.xml b/phpunit.xml
index 829414b..5543800 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -2,7 +2,7 @@
 <phpunit
     backupGlobals="false"
     backupStaticAttributes="false"
-    bootstrap="tests/bootstrap.php"
+    bootstrap="vendor/autoload.php"
     colors="true"
     convertErrorsToExceptions="true"
     convertNoticesToExceptions="true"
diff --git a/src/Deferred.php b/source/Deferred.php
similarity index 100%
rename from src/Deferred.php
rename to source/Deferred.php
diff --git a/source/macros.yay b/source/macros.yay
new file mode 100644
index 0000000..176fd79
--- /dev/null
+++ b/source/macros.yay
@@ -0,0 +1,78 @@
+<?php
+
+macro ·recursion {
+    ·chain(
+        defer,
+        ·between(
+            ·token("{"), ·layer()·body, ·token("}")
+        ),
+        ·optional(·token(";")),
+        ·_()·scope,
+        ·_()·simple
+    )
+} >> function($ast) {
+    $bound = false;
+    $scope = new \Yay\Ast("·scope");
+
+    $pushed = [];
+
+    foreach ($ast->{"·body"} as $token) {
+        $name = $token->value();
+
+        if (!$token->is(T_VARIABLE)) {
+            continue;
+        }
+
+        if (isset($pushed[$name])) {
+            continue;
+        }
+
+        if (substr($name, 1) === "this") {
+            continue;
+        }
+
+        $scope->push(new \Yay\Ast("·var", $token));
+        $pushed[$name] = true;
+        $bound = true;
+    }
+
+    if ($bound) {
+      $ast->append($scope);
+    } else {
+      $simple = new \Yay\Ast("·simple");
+      $simple->push(new \Yay\Ast());
+
+      $ast->append($simple);
+    }
+} >> {
+    ··collapse(··trim(
+        ·scope ?·{
+            $deferred = new \Pre\Deferred\Deferred([·scope ···(, ) { ·var = ·var ?? null}, "fn" => function () use (··trim(·scope ···(, ) {&·var})) {
+                ··trim(·body)
+            }]["fn"]);
+        }
+
+        ·simple ?·{
+            $deferred = new \Pre\Deferred\Deferred(function () {
+                ··trim(·body)
+            });
+        }
+    ))
+}
+
+macro ·recursion {
+    ·chain(
+        defer,
+        ·ns()·function,
+        ·between(
+            ·token("("), ·layer()·parameters, ·token(")")
+        ),
+        ·token(";")
+    )
+} >> {
+    $deferred = ··unsafe(new \Pre\Deferred\Deferred((function (...$parameters) {
+        return function () use ($parameters) {
+            ·function(...$parameters);
+        };
+    })(·parameters)));
+}
diff --git a/src/macros.yay b/src/macros.yay
deleted file mode 100644
index dd4e234..0000000
--- a/src/macros.yay
+++ /dev/null
@@ -1,37 +0,0 @@
-<?php
-
-macro ·recursion {
-    ·chain(
-        defer,
-        ·between(
-            ·token("{"), ·layer()·body, ·token("}")
-        ),
-        ·optional(·token(";"))
-    )
-} >> {
-    $deferred = new \Pre\Deferred\Deferred(call_user_func(function($context) {
-        return function() use ($context) {
-            extract($context);
-            ·body
-        };
-    }, get_defined_vars()));
-}
-
-macro ·recursion {
-    ·chain(
-        defer,
-        ·ns()·function,
-        ·between(
-            ·token("("), ·layer()·parameters, ·token(")")
-        ),
-        ·token(";")
-    )
-} >> {
-    $deferred = new \Pre\Deferred\Deferred(call_user_func(function() {
-        $context = func_get_args();
-
-        return function() use ($context) {
-            call_user_func_array(··stringify(·function), $context);
-        };
-    }, ·parameters));
-}
diff --git a/tests/MacroTest.php b/tests/MacroTest.php
index ee7d41e..7e12dbd 100644
--- a/tests/MacroTest.php
+++ b/tests/MacroTest.php
@@ -1,13 +1,42 @@
 <?php
 
-namespace Pre\Deferred;
+use PHPUnit\Framework\TestCase;
 
-use Pre\Plugin\Testing\Runner;
-
-class MacroTest extends Runner
+class MacroTest extends TestCase
 {
-    protected function path(): string
+    /**
+     * @test
+     * @dataProvider specs
+     */
+    public function can_transform_code($from, $expected)
+    {
+        \Pre\Plugin\addMacro(__DIR__ . "/../source/macros.yay");
+
+        $actual = \Pre\plugin\format(\Pre\Plugin\parse($this->format($from)));
+        $this->assertEquals($this->format($expected), $actual);
+    }
+
+    private function format($code)
     {
-        return __DIR__ . "/specs";
+        return "<?php\n\n" . trim($code) . "\n";
+    }
+
+    public static function specs()
+    {
+        $specs = [];
+
+        $files = [
+            __DIR__ . "/specs/deferred.spec",
+        ];
+
+        foreach ($files as $file) {
+            $contents = file_get_contents($file);
+            
+            foreach (explode("---", $contents) as $spec) {
+                array_push($specs, explode("~~~", $spec));
+            }
+        }
+
+        return $specs;
     }
 }
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
deleted file mode 100644
index e45a934..0000000
--- a/tests/bootstrap.php
+++ /dev/null
@@ -1,18 +0,0 @@
-<?php
-
-namespace
-{
-    require __DIR__ . "/../vendor/autoload.php";
-
-    putenv("PRE_BASE_DIR=" . __DIR__ . "/../");
-
-    Pre\Plugin\addMacroPath(__DIR__ . "/../src/macros.yay");
-}
-
-namespace Yay
-{
-    function md5($value)
-    {
-        return $value;
-    }
-}
diff --git a/tests/specs/deferred.spec b/tests/specs/deferred.spec
index e7c7020..fbad6db 100644
--- a/tests/specs/deferred.spec
+++ b/tests/specs/deferred.spec
@@ -1,30 +1,23 @@
---DESCRIPTION--
+defer unlink("path/to/file");
 
-Test deferred
+~~~
 
---GIVEN--
+$deferred·0 = new \Pre\Deferred\Deferred((function (...$parameters) {
+    return function () use ($parameters) {
+        unlink(...$parameters);
+    };
+})("path/to/file"));
 
-defer unlink("path/to/file");
+---
 
 defer {
     fclose($handle);
     print "all done";
 }
 
---EXPECT--
+~~~
 
-$deferred·0 = new \Pre\Deferred\Deferred(call_user_func(function () {
-    $context·0 = func_get_args();
-
-    return function () use ($context·0) {
-        call_user_func_array('unlink', $context·0);
-    };
-}, "path/to/file"));
-
-$deferred·1 = new \Pre\Deferred\Deferred(call_user_func(function ($context·1) {
-    return function () use ($context·1) {
-        extract($context·1);
-        fclose($handle);
-        print "all done";
-    };
-}, get_defined_vars()));
+$deferred·0 = new \Pre\Deferred\Deferred([$handle = $handle ?? null, "fn" => function () use (&$handle) {
+    fclose($handle);
+    print "all done";
+}]["fn"]);
diff --git a/tests/stubs.php b/tests/stubs.php
new file mode 100644
index 0000000..d714f68
--- /dev/null
+++ b/tests/stubs.php
@@ -0,0 +1,9 @@
+<?php
+
+namespace Yay
+{
+    function md5($foo)
+    {
+        return $foo;
+    }
+}