diff --git a/build-phar.php b/build-phar.php
new file mode 100644
index 000000000..68c4dd8c5
--- /dev/null
+++ b/build-phar.php
@@ -0,0 +1,10 @@
+<?php
+
+@unlink('demo.phar');
+$phar = new Phar('demo.phar');
+$phar->addFile('composer.json');
+$phar->addFile('composer.lock');
+$phar->compressFiles(Phar::BZ2);
+
+$x = new PharFileInfo('phar://demo.phar/composer.lock');
+$x->compress(Phar::GZ);
diff --git a/src/Console/Command/Diff.php b/src/Console/Command/Diff.php
index a77a21f0d..2229e53f2 100644
--- a/src/Console/Command/Diff.php
+++ b/src/Console/Command/Diff.php
@@ -29,6 +29,8 @@
 use Throwable;
 use Webmozart\Assert\Assert;
 use function array_map;
+use function array_search;
+use function array_sum;
 use function count;
 // TODO: migrate to Safe API
 use function is_string;
@@ -122,10 +124,13 @@ public function execute(IO $io): int
             return ExitCode::FAILURE;
         }
 
-        $result1 = $this->compareArchives($diff, $io);
-        $result2 = $this->compareContents($diff, $io);
+        $results = [
+            $this->compareCheckSums($diff, $io),
+            $this->compareArchives($diff, $io),
+            $this->compareContents($diff, $io),
+        ];
 
-        return $result1 + $result2;
+        return array_sum($results);
     }
 
     /**
@@ -146,6 +151,37 @@ private static function getPaths(IO $io): array
         );
     }
 
+    private function compareCheckSums(PharDiff $diff, IO $io): int
+    {
+        $io->comment('<info>Comparing the two archives... (do not check the signatures)</info>');
+
+        $pharInfoA = $diff->getPharA()->getPharInfo();
+        $pharInfoB = $diff->getPharB()->getPharInfo();
+
+        if ($pharInfoA->equals($pharInfoB)) {
+            $io->success('The two archives are identical');
+
+            return ExitCode::SUCCESS;
+        }
+
+        self::renderArchive(
+            $diff->getPharA()->getFileName(),
+            $pharInfoA,
+            $io,
+        );
+
+        $io->newLine();
+
+        self::renderArchive(
+            $diff->getPharB()->getFileName(),
+            $pharInfoB,
+            $io,
+        );
+
+        return ExitCode::FAILURE;
+    }
+
+
     private function compareArchives(PharDiff $diff, IO $io): int
     {
         $io->comment('<info>Comparing the two archives... (do not check the signatures)</info>');
diff --git a/src/Pharaoh/Pharaoh.php b/src/Pharaoh/Pharaoh.php
index bc3c2e191..3a12f8e38 100644
--- a/src/Pharaoh/Pharaoh.php
+++ b/src/Pharaoh/Pharaoh.php
@@ -51,6 +51,7 @@
 use function file_exists;
 use function file_put_contents;
 use function KevinGH\Box\FileSystem\copy;
+use function KevinGH\Box\FileSystem\dump_file;
 use function KevinGH\Box\FileSystem\mkdir;
 use function KevinGH\Box\FileSystem\remove;
 use function KevinGH\Box\FileSystem\tempnam;
@@ -58,55 +59,33 @@
 use function sys_get_temp_dir;
 use const DIRECTORY_SEPARATOR;
 
+/**
+ * Pharaoh is a wrapper around Phar
+ */
 final class Pharaoh
 {
-    public Phar $phar;
-
-    public string $tmp;
-
-    public static string $stubfile;
+    private static string $stubfile;
 
+    private Phar $phar;
+    private string $tmp;
     private string $fileName;
     private ?PharInfo $pharInfo = null;
     private ?string $path = null;
 
-    public function __construct(string $file, ?string $alias = null)
+    public function __construct(string $file)
     {
         Assert::readable($file);
-        Assert::true(
+        Assert::false(
             PharPhpSettings::isReadonly(),
             'Pharaoh cannot be used if phar.readonly is enabled in php.ini',
         );
 
-        // Set the static variable here
-        if (!isset(self::$stubfile)) {
-            self::$stubfile = Hex::encode(random_bytes(12)).'.pharstub';
-        }
-
-        // We have to give every one a different alias, or it pukes.
-        $alias ??= (Hex::encode(random_bytes(16)).'.phar');
-
-        $tmpFile = sys_get_temp_dir().DIRECTORY_SEPARATOR.$alias;
-        copy($file, $tmpFile);
-
-        $phar = new Phar($tmpFile);
-        $phar->setAlias($alias);
-
-        // Make a random folder in /tmp
-        /** @var string|bool $tmp */
-        $tmp = tempnam(sys_get_temp_dir(), 'phr_');
+        self::initStubFileName();
 
-        Assert::false(file_exists($tmp));
-        mkdir($tmp, 0o755);
-
-        // Let's extract to our temporary directory
-        $phar->extractTo($tmp);
+        $tmp = self::createTmpDir();
+        $phar = self::createTmpPhar($file);
 
-        // Also extract the stub
-        file_put_contents(
-            $tmp.'/'.self::$stubfile,
-            $phar->getStub()
-        );
+        self::extractPhar($phar, $tmp);
 
         $this->tmp = $tmp;
         $this->phar = $phar;
@@ -139,4 +118,48 @@ public function getPharInfo(): PharInfo
 
         return $this->pharInfo;
     }
+
+    private static function initStubFileName(): void
+    {
+        if (!isset(self::$stubfile)) {
+            self::$stubfile = Hex::encode(random_bytes(12)).'.pharstub';
+        }
+    }
+
+    private static function createTmpPhar(string $file): Phar
+    {
+        // We have to give every one a different alias, or it pukes.
+        $alias = Hex::encode(random_bytes(16)).'.phar';
+
+        $tmpFile = sys_get_temp_dir().DIRECTORY_SEPARATOR.$alias;
+        copy($file, $tmpFile);
+
+        $phar = new Phar($tmpFile);
+        $phar->setAlias($alias);
+
+        return $phar;
+    }
+
+    private static function createTmpDir(): string
+    {
+        $tmp = tempnam(sys_get_temp_dir(), 'box_');
+
+        remove($tmp);
+        mkdir($tmp, 0o755);
+
+        return $tmp;
+    }
+
+    private static function extractPhar(Phar $phar, string $tmp): void
+    {
+        // Extract the PHAR content
+        $phar->extractTo($tmp);
+
+        // Extract the stub; Phar::extractTo() does not do it since it
+        // is internal to the PHAR.
+        dump_file(
+            $tmp.DIRECTORY_SEPARATOR.self::$stubfile,
+            $phar->getStub(),
+        );
+    }
 }