diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index d1dd269..f2f21b5 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -8,7 +8,7 @@ jobs:
             fail-fast: false
             matrix:
                 operating-system: [ ubuntu-latest ]
-                php-versions: [ '7.4', '8.0', '8.1' ]
+                php-versions: [ '7.4', '8.0', '8.1', '8.4' ]
                 composer-dependencies: [ '', '--prefer-lowest' ]
                 extra-label: [ '' ]
                 include:
@@ -28,6 +28,11 @@ jobs:
                         operating-system: windows-latest
                         coverage: xdebug
 
+                    # Windows
+                    -   php-versions: '8.4'
+                        operating-system: windows-latest
+                        coverage: xdebug
+
         steps:
             # see https://github.com/actions/checkout/issues/226#issue-606867805
             -   name: Prepare git
diff --git a/.gitignore b/.gitignore
index c8002c6..a46912d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,6 @@ phpunit.xml
 composer.lock
 build/
 /.phpunit.result.cache
+/docker/
+/.idea/
+/Makefile
diff --git a/composer.json b/composer.json
index 5fd13dd..347414a 100644
--- a/composer.json
+++ b/composer.json
@@ -25,11 +25,11 @@
     "composer/ca-bundle": "^1.5"
   },
   "require-dev": {
-    "phpunit/phpunit": "9.5.10",
+    "phpunit/phpunit": "^9.6",
     "squizlabs/php_codesniffer": "3.6.1",
-    "phpstan/phpstan": "1.11.5",
-    "phpstan/phpstan-phpunit": "1.4.0",
-    "phpstan/phpstan-strict-rules": "1.6.0"
+    "phpstan/phpstan": "^2.1",
+    "phpstan/phpstan-phpunit": "^2.0",
+    "phpstan/phpstan-strict-rules": "^2.0"
   },
   "autoload": {
     "psr-4": {
diff --git a/src/FioApi/Downloader.php b/src/FioApi/Downloader.php
index 89682e3..0ab7783 100644
--- a/src/FioApi/Downloader.php
+++ b/src/FioApi/Downloader.php
@@ -9,9 +9,7 @@
 use GuzzleHttp\Client;
 use GuzzleHttp\ClientInterface;
 use GuzzleHttp\Exception\BadResponseException;
-use GuzzleHttp\Exception\GuzzleException;
 use GuzzleHttp\RequestOptions;
-use Psr\Http\Message\ResponseInterface;
 
 class Downloader
 {
@@ -21,7 +19,7 @@ class Downloader
     /** @var ?ClientInterface */
     protected $client;
 
-    public function __construct(string $token, ClientInterface $client = null)
+    public function __construct(string $token, ?ClientInterface $client = null)
     {
         $this->urlBuilder = new UrlBuilder($token);
         $this->client = $client;
@@ -84,10 +82,10 @@ private function downloadTransactionsList(string $url): TransactionList
 
     private function handleException(BadResponseException $e): void
     {
-        if ($e->getCode() == 409) {
+        if ($e->getCode() === 409) {
             throw new TooGreedyException('You can use one token for API call every 30 seconds', $e->getCode(), $e);
         }
-        if ($e->getCode() == 500) {
+        if ($e->getCode() === 500) {
             throw new InternalErrorException(
                 'Server returned 500 Internal Error (probably invalid token?)',
                 $e->getCode(),
diff --git a/tests/FioApi/DownloaderTest.php b/tests/FioApi/DownloaderTest.php
index d07eb76..f557ec7 100644
--- a/tests/FioApi/DownloaderTest.php
+++ b/tests/FioApi/DownloaderTest.php
@@ -75,6 +75,7 @@ public function testDownloaderDownloadsLast(): void
 
     public function testDownloaderSetsLastId(): void
     {
+        /** @var array<int, array{request: \Psr\Http\Message\RequestInterface}> $container */
         $container = [];
         $history = Middleware::history($container);
 
@@ -86,9 +87,10 @@ public function testDownloaderSetsLastId(): void
 
         $downloader->setLastId('123456');
 
+        Assert::assertIsArray($container);
         Assert::assertCount(1, $container);
 
-        /** @var \GuzzleHttp\Psr7\Request $request */
+        /** @var \Psr\Http\Message\RequestInterface $request */
         $request = $container[0]['request'];
 
         Assert::assertSame('https://fioapi.fio.cz/v1/rest/set-last-id/validToken/123456/', (string) $request->getUri());