diff --git a/composer.json b/composer.json
index a0c6733..13a8249 100644
--- a/composer.json
+++ b/composer.json
@@ -24,14 +24,14 @@
         }
     },
     "require": {
-        "php": "~8.1.0 || ~8.2.0"
+        "php": "~8.1.0 || ~8.2.0 || ~8.3.0"
     },
     "require-dev": {
         "laminas/laminas-coding-standard": "~2.5.0",
         "mikey179/vfsstream": "^1.6.11",
-        "phpunit/phpunit": "^10.2.2",
+        "phpunit/phpunit": "^10.4.2",
         "psalm/plugin-phpunit": "^0.18.4",
-        "vimeo/psalm": "^5.13.1"
+        "vimeo/psalm": "^5.15.0"
     },
     "autoload": {
         "psr-4": {
diff --git a/composer.lock b/composer.lock
index eb5d1d5..9d736bf 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "c441ac3435d26bdb29789c5d24f61310",
+    "content-hash": "51773f1a3f57c4dab1c71a87060a5e70",
     "packages": [],
     "packages-dev": [
         {
@@ -4009,7 +4009,7 @@
     "prefer-stable": false,
     "prefer-lowest": false,
     "platform": {
-        "php": "~8.1.0 || ~8.2.0"
+        "php": "~8.1.0 || ~8.2.0 || ~8.3.0"
     },
     "platform-dev": [],
     "platform-overrides": {
diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index ae4fada..b40544e 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -1,11 +1,14 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<files psalm-version="5.13.1@086b94371304750d1c673315321a55d15fc59015">
+<files psalm-version="5.15.0@5c774aca4746caf3d239d9c8cadb9f882ca29352">
   <file src="src/Command.php">
     <MixedAssignment>
       <code>$argument</code>
     </MixedAssignment>
   </file>
   <file src="src/ConfigDiscoveryTrait.php">
+    <DocblockTypeContradiction>
+      <code><![CDATA[$this->applicationConfigPath]]></code>
+    </DocblockTypeContradiction>
     <MissingReturnType>
       <code>removeConfigCacheFile</code>
     </MissingReturnType>
@@ -20,9 +23,6 @@
     <RedundantConditionGivenDocblockType>
       <code><![CDATA[isset($this->projectDir)]]></code>
     </RedundantConditionGivenDocblockType>
-    <DocblockTypeContradiction>
-      <code><![CDATA[$this->applicationConfigPath]]></code>
-    </DocblockTypeContradiction>
   </file>
   <file src="test/AutoComposerTest.php">
     <InvalidPropertyAssignmentValue>
diff --git a/psalm.xml b/psalm.xml
index 62df690..db03cfd 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -5,9 +5,13 @@
     xmlns="https://getpsalm.org/schema/config"
     xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
     errorBaseline="psalm-baseline.xml"
+    findUnusedCode="true"
+    findUnusedBaselineEntry="true"
+    findUnusedPsalmSuppress="true"
 >
     <projectFiles>
         <directory name="src"/>
+        <directory name="bin"/>
         <directory name="test"/>
         <ignoreFiles>
             <directory name="vendor"/>
diff --git a/src/AutoComposer.php b/src/AutoComposer.php
index 5473614..3f97516 100644
--- a/src/AutoComposer.php
+++ b/src/AutoComposer.php
@@ -34,12 +34,6 @@ class AutoComposer
     /** @var resource */
     private $errorStream;
 
-    /** @var string[] */
-    private array $expectedValues = [
-        '0', // production mode
-        '1', // development mode
-    ];
-
     /**
      * @param string $projectDir Location to resolve project from.
      * @param null|resource $errorStream Stream to which to write errors; defaults to STDERR
diff --git a/test/AutoComposerTest.php b/test/AutoComposerTest.php
index 7d15475..c8ce6bb 100644
--- a/test/AutoComposerTest.php
+++ b/test/AutoComposerTest.php
@@ -19,6 +19,7 @@ class AutoComposerTest extends TestCase
 {
     use RemoveCacheFileTrait;
 
+    /** @psalm-suppress UnusedProperty */
     private vfsStreamContainer $projectDir;
 
     /** @var resource */
diff --git a/test/CommandTest.php b/test/CommandTest.php
new file mode 100644
index 0000000..43d14c9
--- /dev/null
+++ b/test/CommandTest.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LaminasTest\DevelopmentMode;
+
+use Laminas\DevelopmentMode\Command;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+
+#[CoversClass(Command::class)]
+final class CommandTest extends TestCase
+{
+    public function testExitCodeWithNoArguments(): void
+    {
+        self::assertSame(1, (new Command())([]));
+    }
+
+    public function testExitCodeWithHelpArgument(): void
+    {
+        self::assertSame(0, (new Command())(['-h']));
+        self::assertSame(0, (new Command())(['--help']));
+    }
+}