diff --git a/.gitignore b/.gitignore
index 1ca53917d..a44c25f7b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,4 @@
-/bin/psalm.phar
+/build/
 /vendor/
 /.DS_Store
 /.php_cs.cache
diff --git a/bin/build-phar.sh b/bin/build-phar.sh
index 493f93a20..15dbaca20 100755
--- a/bin/build-phar.sh
+++ b/bin/build-phar.sh
@@ -1,11 +1,6 @@
 #!/usr/bin/env bash
-if ! php -r 'extension_loaded("bz2") or exit(1);' ; then
-	echo "You need to install (or enable) bz2 php extension"
-	exit 1
-fi
-
 composer bin box install
 
 vendor/bin/box compile
 
-bin/psalm.phar  --config=bin/phar.psalm.xml --root=src
+build/psalm.phar --config=bin/phar.psalm.xml
diff --git a/box.json.dist b/box.json.dist
index 1077461ac..c927932ff 100644
--- a/box.json.dist
+++ b/box.json.dist
@@ -1,16 +1,12 @@
 {
-    "main" : "psalm",
-    "output" : "bin/psalm.phar",
-    "directories" : [
-        "assets",
-        "src",
-        "vendor"
-    ],
-    "files" : [
-        "composer.json",
-        "composer.lock",
-        "config.xsd"
+    "output" : "build/psalm.phar",
+    "files": [
+        "src/command_functions.php",
+        "src/psalm.php",
+        "src/psalter.php"
     ],
+    "files-bin": ["config.xsd"],
+    "directories-bin" : ["assets"],
     "intercept" : false,
     "compactors" : [
         "KevinGH\\Box\\Compactor\\PhpScoper"
diff --git a/scoper.inc.php b/scoper.inc.php
index 677dae19b..dedd86dc9 100644
--- a/scoper.inc.php
+++ b/scoper.inc.php
@@ -18,6 +18,13 @@ return [
 
             return $contents;
         },
+        function ($filePath, $prefix, $contents) {
+            return str_replace(
+                '\\'.$prefix.'\Composer\Autoload\ClassLoader',
+                '\Composer\Autoload\ClassLoader',
+                $contents
+            );
+        },
         function ($filePath, $prefix, $contents) {
             if ($filePath === realpath(__DIR__ . '/src/Psalm/Config.php')) {
                 return str_replace(
@@ -108,4 +115,7 @@ return [
             return $contents;
         },
     ],
+    'whitelist' => [
+        \Composer\Autoload\ClassLoader::class,
+    ]
 ];