diff --git a/src/Commands/Check.php b/src/Commands/Check.php
index d65f695..0c910ef 100644
--- a/src/Commands/Check.php
+++ b/src/Commands/Check.php
@@ -26,7 +26,7 @@ class Check implements Command {
         $server = \Kelunik\AcmeClient\resolveServer($args->get("server"));
         $server = \Kelunik\AcmeClient\serverToKeyname($server);
 
-        $path = dirname(dirname(__DIR__)) . "/data/certs/" . $server;
+        $path = \Kelunik\AcmeClient\normalizePath($args->get("storage")) . "/certs/" . $server;
         $certificateStore = new CertificateStore($path);
 
         $pem = (yield $certificateStore->get($args->get("name")));
@@ -35,20 +35,22 @@ class Check implements Command {
         $this->climate->info("Certificate is valid until " . date("d.m.Y", $cert->getValidTo()));
 
         if ($cert->getValidTo() > time() + $args->get("ttl") * 24 * 60 * 60) {
-            exit(0);
+            return 0;
         }
 
         $this->climate->comment("Certificate is going to expire within the specified " . $args->get("ttl") . " days.");
 
-        exit(1);
+        return 1;
     }
 
     public static function getDefinition() {
+        $isPhar = \Kelunik\AcmeClient\isPhar();
+
         return [
             "server" => [
                 "prefix" => "s",
                 "longPrefix" => "server",
-                "description" => "",
+                "description" => "ACME server to use for registration and issuance of certificates.",
                 "required" => true,
             ],
             "name" => [
@@ -62,6 +64,12 @@ class Check implements Command {
                 "defaultValue" => 30,
                 "castTo" => "int",
             ],
+            "storage" => [
+                "longPrefix" => "storage",
+                "description" => "Storage directory for account keys and certificates.",
+                "required" => $isPhar,
+                "defaultValue" => $isPhar ? null : (__DIR__ . "/../../data")
+            ]
         ];
     }
 }
\ No newline at end of file
diff --git a/src/Commands/Issue.php b/src/Commands/Issue.php
index ae134f2..cf1e30e 100644
--- a/src/Commands/Issue.php
+++ b/src/Commands/Issue.php
@@ -63,7 +63,7 @@ class Issue implements Command {
             );
         }
 
-        $keyStore = new KeyStore(dirname(dirname(__DIR__)) . "/data");
+        $keyStore = new KeyStore(\Kelunik\AcmeClient\normalizePath($args->get("storage")));
 
         $server = \Kelunik\AcmeClient\resolveServer($args->get("server"));
         $keyFile = \Kelunik\AcmeClient\serverToKeyname($server);
@@ -71,9 +71,7 @@ class Issue implements Command {
         try {
             $keyPair = (yield $keyStore->get("accounts/{$keyFile}.pem"));
         } catch (KeyStoreException $e) {
-            $this->climate->error("Account key not found, did you run 'bin/acme setup'?");
-
-            exit(1);
+            throw new AcmeException("Account key not found, did you run 'bin/acme setup'?", 0, $e);
         }
 
         $acme = new AcmeService(new AcmeClient($server, $keyPair));
@@ -109,11 +107,13 @@ class Issue implements Command {
         $location = (yield $acme->requestCertificate($keyPair, $domains));
         $certificates = (yield $acme->pollForCertificate($location));
 
-        $path = dirname(dirname(__DIR__)) . "/data/certs/" . $keyFile;
+        $path = \Kelunik\AcmeClient\normalizePath($args->get("storage")) . "/certs/" . $keyFile;
         $certificateStore = new CertificateStore($path);
         yield $certificateStore->put($certificates);
 
         $this->climate->info("Successfully issued certificate, see {$path}/" . reset($domains));
+
+        return 0;
     }
 
     private function solveChallenge(AcmeService $acme, KeyPair $keyPair, $domain, $path) {
@@ -196,11 +196,13 @@ class Issue implements Command {
     }
 
     public static function getDefinition() {
+        $isPhar = \Kelunik\AcmeClient\isPhar();
+
         return [
             "server" => [
                 "prefix" => "s",
                 "longPrefix" => "server",
-                "description" => "Server to use for issuance, see also 'bin/acme setup'.",
+                "description" => "ACME server to use for registration and issuance of certificates.",
                 "required" => true,
             ],
             "domains" => [
@@ -226,6 +228,12 @@ class Issue implements Command {
                 "defaultValue" => 2048,
                 "castTo" => "int",
             ],
+            "storage" => [
+                "longPrefix" => "storage",
+                "description" => "Storage directory for account keys and certificates.",
+                "required" => $isPhar,
+                "defaultValue" => $isPhar ? null : (__DIR__ . "/../../data")
+            ]
         ];
     }
 }
\ No newline at end of file
diff --git a/src/Commands/Revoke.php b/src/Commands/Revoke.php
index b537beb..602f47f 100644
--- a/src/Commands/Revoke.php
+++ b/src/Commands/Revoke.php
@@ -23,7 +23,7 @@ class Revoke implements Command {
     }
 
     private function doExecute(Manager $args) {
-        $keyStore = new KeyStore(dirname(dirname(__DIR__)) . "/data");
+        $keyStore = new KeyStore(\Kelunik\AcmeClient\normalizePath($args->get("storage")));
 
         $server = \Kelunik\AcmeClient\resolveServer($args->get("server"));
         $keyFile = \Kelunik\AcmeClient\serverToKeyname($server);
@@ -33,7 +33,7 @@ class Revoke implements Command {
 
         $this->climate->info("Revoking certificate ...");
 
-        $path = dirname(dirname(__DIR__)) . "/data/certs/" . $keyFile . "/" . $args->get("name") . "/cert.pem";
+        $path = \Kelunik\AcmeClient\normalizePath($args->get("storage")) . "/certs/" . $keyFile . "/" . $args->get("name") . "/cert.pem";
 
         try {
             $pem = (yield \Amp\File\get($path));
@@ -50,15 +50,19 @@ class Revoke implements Command {
         yield $acme->revokeCertificate($pem);
         $this->climate->info("Certificate has been revoked.");
 
-        yield (new CertificateStore(dirname(dirname(__DIR__)) . "/data/certs/" . $keyFile))->delete($args->get("name"));
+        yield (new CertificateStore(\Kelunik\AcmeClient\normalizePath($args->get("storage")). "/certs/" . $keyFile))->delete($args->get("name"));
+
+        return 0;
     }
 
     public static function getDefinition() {
+        $isPhar = \Kelunik\AcmeClient\isPhar();
+
         return [
             "server" => [
                 "prefix" => "s",
                 "longPrefix" => "server",
-                "description" => "",
+                "description" => "ACME server to use for registration and issuance of certificates.",
                 "required" => true,
             ],
             "name" => [
@@ -66,6 +70,12 @@ class Revoke implements Command {
                 "description" => "Common name of the certificate to be revoked.",
                 "required" => true,
             ],
+            "storage" => [
+                "longPrefix" => "storage",
+                "description" => "Storage directory for account keys and certificates.",
+                "required" => $isPhar,
+                "defaultValue" => $isPhar ? null : (__DIR__ . "/../../data")
+            ]
         ];
     }
 }
\ No newline at end of file
diff --git a/src/Commands/Setup.php b/src/Commands/Setup.php
index 843c737..e9efc27 100644
--- a/src/Commands/Setup.php
+++ b/src/Commands/Setup.php
@@ -36,7 +36,7 @@ class Setup implements Command {
         $path = "accounts/{$keyFile}.pem";
         $bits = 4096;
 
-        $keyStore = new KeyStore(dirname(dirname(__DIR__)) . "/data");
+        $keyStore = new KeyStore(\Kelunik\AcmeClient\normalizePath($args->get("storage")) . "/data");
 
         try {
             $keyPair = (yield $keyStore->get($path));
@@ -78,6 +78,8 @@ class Setup implements Command {
     }
 
     public static function getDefinition() {
+        $isPhar = \Kelunik\AcmeClient\isPhar();
+
         return [
             "server" => [
                 "prefix" => "s",
@@ -87,9 +89,15 @@ class Setup implements Command {
             ],
             "email" => [
                 "longPrefix" => "email",
-                "description" => "Email for important issues, will be sent to the ACME server.",
+                "description" => "E-mail for important issues, will be sent to the ACME server.",
                 "required" => true,
             ],
+            "storage" => [
+                "longPrefix" => "storage",
+                "description" => "Storage directory for account keys and certificates.",
+                "required" => $isPhar,
+                "defaultValue" => $isPhar ? null : (__DIR__ . "/../../data")
+            ]
         ];
     }
 }
\ No newline at end of file
diff --git a/src/functions.php b/src/functions.php
index 4f566ce..9592d0b 100644
--- a/src/functions.php
+++ b/src/functions.php
@@ -2,6 +2,7 @@
 
 namespace Kelunik\AcmeClient;
 
+use Phar;
 use Webmozart\Assert\Assert;
 
 function suggestCommand($badCommand, array $commands, $suggestThreshold = 70) {
@@ -56,4 +57,16 @@ function serverToKeyname($server) {
     $keyFile = preg_replace("@\\.+@", ".", $keyFile);
 
     return $keyFile;
+}
+
+function isPhar() {
+    if (!class_exists("Phar")) {
+        return false;
+    }
+
+    return Phar::running(true) !== "";
+}
+
+function normalizePath($path) {
+    return rtrim(str_replace("\\", "/", $path), "/");
 }
\ No newline at end of file
diff --git a/test/FunctionsTest.php b/test/FunctionsTest.php
index f48c771..4013eea 100644
--- a/test/FunctionsTest.php
+++ b/test/FunctionsTest.php
@@ -15,4 +15,15 @@ class FunctionsTest extends \PHPUnit_Framework_TestCase {
         $this->assertSame("acme", suggestCommand("acme!", ["acme"]));
         $this->assertSame("", suggestCommand("issue", ["acme"]));
     }
+
+    public function testIsPhar() {
+        $this->assertFalse(isPhar());
+    }
+
+    public function testNormalizePath() {
+        $this->assertSame("/etc/foobar", normalizePath("/etc/foobar"));
+        $this->assertSame("/etc/foobar", normalizePath("/etc/foobar/"));
+        $this->assertSame("/etc/foobar", normalizePath("/etc/foobar/"));
+        $this->assertSame("C:/etc/foobar", normalizePath("C:\\etc\\foobar\\"));
+    }
 }
\ No newline at end of file