diff --git a/bin/slim b/bin/slim
index 9896594..036fc1c 100755
--- a/bin/slim
+++ b/bin/slim
@@ -9,7 +9,10 @@
 
 declare(strict_types=1);
 
-use Slim\Console\Application;
+use Slim\Console\App;
+use Slim\Console\Config\ConfigResolver;
+
+$cwd = getcwd();
 
 if (file_exists(__DIR__ . '/../../../autoload.php')) {
     require __DIR__ . '/../../../autoload.php';
@@ -17,5 +20,7 @@ if (file_exists(__DIR__ . '/../../../autoload.php')) {
     require __DIR__ . '/../vendor/autoload.php';
 }
 
-$app = new Application();
+$config = (new ConfigResolver())->resolve($cwd);
+
+$app = new App($config);
 $app->run();
diff --git a/composer.json b/composer.json
index 1a124ca..c3857f2 100644
--- a/composer.json
+++ b/composer.json
@@ -13,14 +13,14 @@
         }
     ],
     "require": {
+        "ext-json": "*",
         "php": "^7.2",
-        "symfony/console": "^5.0",
-        "symfony/config": "^5.0"
+        "symfony/console": "^5.0"
     },
     "require-dev": {
         "adriansuter/php-autoload-override": "^1.0",
         "phpspec/prophecy": "^1.10",
-        "phpstan/phpstan": "^0.12.19",
+        "phpstan/phpstan": "^0.12.23",
         "phpunit/phpunit": "^8.5",
         "squizlabs/php_codesniffer": "^3.5"
     },
diff --git a/src/Application.php b/src/App.php
similarity index 70%
rename from src/Application.php
rename to src/App.php
index 5f85abe..2d27487 100644
--- a/src/Application.php
+++ b/src/App.php
@@ -10,18 +10,31 @@
 
 namespace Slim\Console;
 
+use Slim\Console\Config\Config;
 use Symfony\Component\Console\Application as SymfonyApplication;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Output\OutputInterface;
 use Throwable;
 
-class Application extends SymfonyApplication
+class App extends SymfonyApplication
 {
-    private const VERSION = '0.1';
+    protected const NAME = 'Slim Console';
 
-    public function __construct()
+    protected const VERSION = '0.1';
+
+    /**
+     * @var Config
+     */
+    protected $config;
+
+    /**
+     * @param Config $config
+     */
+    public function __construct(Config $config)
     {
-        parent::__construct('Slim Console', self::VERSION);
+        parent::__construct(static::NAME, static::VERSION);
+
+        $this->config = $config;
     }
 
     /**
@@ -48,4 +61,12 @@ public function doRun(InputInterface $input, OutputInterface $output): int
 
         return parent::doRun($input, $output);
     }
+
+    /**
+     * @return Config
+     */
+    public function getConfig(): Config
+    {
+        return $this->config;
+    }
 }
diff --git a/src/Command/AbstractCommand.php b/src/Command/AbstractCommand.php
new file mode 100644
index 0000000..949c360
--- /dev/null
+++ b/src/Command/AbstractCommand.php
@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Command;
+
+use RuntimeException;
+use Slim\Console\App;
+use Slim\Console\Config\Config;
+use Symfony\Component\Console\Command\Command;
+
+abstract class AbstractCommand extends Command
+{
+    /**
+     * @return Config|null
+     *
+     * @throws RuntimeException
+     */
+    public function getConfig(): ?Config
+    {
+        $app = $this->getApplication();
+
+        if ($app instanceof App === false) {
+            throw new RuntimeException(
+                'Usage of the method `getConfig()` requires the parent application to be a Slim Console Application.'
+            );
+        }
+
+        return $app->getConfig();
+    }
+}
diff --git a/src/Config/Config.php b/src/Config/Config.php
new file mode 100644
index 0000000..8a80dd8
--- /dev/null
+++ b/src/Config/Config.php
@@ -0,0 +1,213 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Config;
+
+use InvalidArgumentException;
+
+class Config
+{
+    public const SLIM_CONSOLE_BOOTSTRAP_DIR = 'SLIM_CONSOLE_BOOTSTRAP_DIR';
+    public const SLIM_CONSOLE_INDEX_DIR = 'SLIM_CONSOLE_INDEX_DIR';
+    public const SLIM_CONSOLE_INDEX_FILE = 'SLIM_CONSOLE_INDEX_FILE';
+    public const SLIM_CONSOLE_SOURCE_DIR = 'SLIM_CONSOLE_SOURCE_DIR';
+    public const SLIM_CONSOLE_COMMANDS_DIR = 'SLIM_CONSOLE_COMMANDS_DIR';
+
+    /**
+     * @var array<string, string>
+     */
+    protected static $defaults = [
+        'bootstrapDir' => 'app',
+        'indexDir' => 'public',
+        'indexFile' => 'index.php',
+        'sourceDir' => 'src',
+        'commandsDir' => 'src'
+            . DIRECTORY_SEPARATOR
+            . 'Application'
+            . DIRECTORY_SEPARATOR
+            . 'Console'
+            . DIRECTORY_SEPARATOR
+            . 'Commands',
+    ];
+
+    /**
+     * @var string
+     */
+    protected $bootstrapDir;
+
+    /**
+     * @var string
+     */
+    protected $indexDir;
+
+    /**
+     * @var string
+     */
+    protected $indexFile;
+
+    /**
+     * @var string
+     */
+    protected $sourceDir;
+
+    /**
+     * @var string|null
+     */
+    protected $commandsDir;
+
+    /**
+     * @param string      $bootstrapDir
+     * @param string      $indexDir
+     * @param string      $indexFile
+     * @param string      $sourceDir
+     * @param string|null $commandsDir
+     */
+    protected function __construct(
+        string $bootstrapDir,
+        string $indexDir,
+        string $indexFile,
+        string $sourceDir,
+        ?string $commandsDir = null
+    ) {
+        $this->bootstrapDir = $bootstrapDir;
+        $this->indexDir = $indexDir;
+        $this->indexFile = $indexFile;
+        $this->sourceDir = $sourceDir;
+        $this->commandsDir = $commandsDir;
+    }
+
+    /**
+     * @return string
+     */
+    public function getBootstrapDir(): string
+    {
+        return $this->bootstrapDir;
+    }
+
+    /**
+     * @return string
+     */
+    public function getIndexDir(): string
+    {
+        return $this->indexDir;
+    }
+
+    /**
+     * @return string
+     */
+    public function getIndexFile(): string
+    {
+        return $this->indexFile;
+    }
+
+    /**
+     * @return string
+     */
+    public function getSourceDir(): string
+    {
+        return $this->sourceDir;
+    }
+
+    /**
+     * @return string|null
+     */
+    public function getCommandsDir(): ?string
+    {
+        return $this->commandsDir;
+    }
+
+    /**
+     * @param array<string, string> $params
+     *
+     * @throws InvalidArgumentException
+     */
+    protected static function validate(array $params): void
+    {
+        [
+            'bootstrapDir' => $bootstrapDir,
+            'indexDir' => $indexDir,
+            'indexFile' => $indexFile,
+            'sourceDir' => $sourceDir,
+            'commandsDir' => $commandsDir,
+        ] = $params;
+
+        if (!is_string($bootstrapDir) || empty($bootstrapDir) || ctype_space($bootstrapDir)) {
+            throw new InvalidArgumentException('`bootstrapDir` must be a string.');
+        }
+
+        if (!is_string($indexDir) || empty($indexDir) || ctype_space($indexDir)) {
+            throw new InvalidArgumentException('`indexDir` must be a string.');
+        }
+
+        if (!is_string($indexFile) || empty($indexFile) || ctype_space($indexFile)) {
+            throw new InvalidArgumentException('`indexFile` must be a string.');
+        }
+
+        if (!is_string($sourceDir) || empty($sourceDir) || ctype_space($sourceDir)) {
+            throw new InvalidArgumentException('`sourceDir` must be a string.');
+        }
+
+        if (!empty($commandsDir) && (!is_string($commandsDir) || ctype_space($commandsDir))) {
+            throw new InvalidArgumentException('`commandsDir` must be a string.');
+        }
+    }
+
+    /**
+     * @param array<string, string> $params
+     *
+     * @return Config
+     *
+     * @throws InvalidArgumentException
+     */
+    public static function fromArray(array $params): Config
+    {
+        $params = array_merge(self::$defaults, $params);
+
+        self::validate($params);
+
+        return new self(
+            $params['bootstrapDir'],
+            $params['indexDir'],
+            $params['indexFile'],
+            $params['sourceDir'],
+            $params['commandsDir']
+        );
+    }
+
+    /**
+     * @return Config
+     *
+     * @throws InvalidArgumentException
+     */
+    public static function fromEnvironment(): Config
+    {
+        return self::fromArray([
+            'bootstrapDir' => (string) getenv(self::SLIM_CONSOLE_BOOTSTRAP_DIR),
+            'indexDir' => (string) getenv(self::SLIM_CONSOLE_INDEX_DIR),
+            'indexFile' => (string) getenv(self::SLIM_CONSOLE_INDEX_FILE),
+            'sourceDir' => (string) getenv(self::SLIM_CONSOLE_SOURCE_DIR),
+            'commandsDir' => (string) getenv(self::SLIM_CONSOLE_COMMANDS_DIR),
+        ]);
+    }
+
+    /**
+     * @return Config
+     */
+    public static function fromDefaults(): Config
+    {
+        return new self(
+            self::$defaults['bootstrapDir'],
+            self::$defaults['indexDir'],
+            self::$defaults['indexFile'],
+            self::$defaults['sourceDir'],
+            self::$defaults['commandsDir']
+        );
+    }
+}
diff --git a/src/Config/ConfigResolver.php b/src/Config/ConfigResolver.php
new file mode 100644
index 0000000..f779553
--- /dev/null
+++ b/src/Config/ConfigResolver.php
@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Config;
+
+use RuntimeException;
+use Slim\Console\Config\Parser\JSONConfigParser;
+use Slim\Console\Config\Parser\PHPConfigParser;
+use Slim\Console\Exception\CannotParseConfigException;
+use Slim\Console\Exception\CannotResolveConfigException;
+
+class ConfigResolver
+{
+    public const CONFIG_FILENAME = 'slim-console.config';
+
+    public const FORMAT_PHP = 'php';
+
+    public const FORMAT_JSON = 'json';
+
+    /**
+     * @var string[]
+     */
+    protected $supportedFormats = [
+        self::FORMAT_PHP,
+        self::FORMAT_JSON,
+    ];
+
+    /**
+     * Resolve configuration. Environment takes precedence over configuration file.
+     *
+     * @param string|null $dir
+     *
+     * @return Config
+     *
+     * @throws CannotParseConfigException
+     * @throws RuntimeException
+     */
+    public function resolve(?string $dir = null): Config
+    {
+        try {
+            return $this->attemptResolvingConfigFromEnvironment();
+        } catch (CannotResolveConfigException $e) {
+            try {
+                return $this->attemptResolvingConfigFromSupportedFormats($dir);
+            } catch (CannotResolveConfigException $e) {
+                return Config::fromDefaults();
+            }
+        }
+    }
+
+    /**
+     * @return Config
+     *
+     * @throws CannotResolveConfigException
+     */
+    protected function attemptResolvingConfigFromEnvironment(): Config
+    {
+        $bootstrapDir = getenv(Config::SLIM_CONSOLE_BOOTSTRAP_DIR);
+        $commandsDir = getenv(Config::SLIM_CONSOLE_COMMANDS_DIR);
+        $indexDir = getenv(Config::SLIM_CONSOLE_INDEX_DIR);
+        $indexFile = getenv(Config::SLIM_CONSOLE_INDEX_FILE);
+        $sourceDir = getenv(Config::SLIM_CONSOLE_SOURCE_DIR);
+
+        if (
+            (is_string($bootstrapDir) && !empty($bootstrapDir) && !ctype_space($bootstrapDir))
+            || (is_string($commandsDir) && !empty($commandsDir) && !ctype_space($commandsDir))
+            || (is_string($indexDir) && !empty($indexDir) && !ctype_space($indexDir))
+            || (is_string($indexFile) && !empty($indexFile) && !ctype_space($indexFile))
+            || (is_string($sourceDir) && !empty($sourceDir) && !ctype_space($sourceDir))
+        ) {
+            return Config::fromEnvironment();
+        }
+
+        throw new CannotResolveConfigException();
+    }
+
+    /**
+     * @param string|null $dir
+     *
+     * @return Config
+     *
+     * @throws CannotResolveConfigException
+     * @throws CannotParseConfigException
+     * @throws RuntimeException
+     */
+    protected function attemptResolvingConfigFromSupportedFormats(?string $dir = null): Config
+    {
+        $dir = $dir ?? getcwd();
+        $basePath = $dir . DIRECTORY_SEPARATOR . self::CONFIG_FILENAME;
+
+        foreach ($this->supportedFormats as $format) {
+            $path = $basePath . ".{$format}";
+            if (is_file($path) && is_readable($path)) {
+                return $this->attemptParsingConfigFromFile($path, $format);
+            }
+        }
+
+        throw new CannotResolveConfigException();
+    }
+
+    /**
+     * @param string $path
+     * @param string $format
+     *
+     * @return Config
+     *
+     * @throws CannotParseConfigException
+     * @throws RuntimeException
+     */
+    protected function attemptParsingConfigFromFile(string $path, string $format): Config
+    {
+        switch ($format) {
+            case self::FORMAT_PHP:
+                return PHPConfigParser::parse($path);
+
+            case self::FORMAT_JSON:
+                return JSONConfigParser::parse($path);
+
+            default:
+                throw new RuntimeException("Invalid configuration format `{$format}`.");
+        }
+    }
+}
diff --git a/src/Config/Parser/ConfigParserInterface.php b/src/Config/Parser/ConfigParserInterface.php
new file mode 100644
index 0000000..3b11003
--- /dev/null
+++ b/src/Config/Parser/ConfigParserInterface.php
@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Config\Parser;
+
+use Slim\Console\Config\Config;
+use Slim\Console\Exception\CannotParseConfigException;
+
+interface ConfigParserInterface
+{
+    /**
+     * @param string $path
+     *
+     * @return Config
+     *
+     * @throws CannotParseConfigException
+     */
+    public static function parse(string $path): Config;
+}
diff --git a/src/Config/Parser/JSONConfigParser.php b/src/Config/Parser/JSONConfigParser.php
new file mode 100644
index 0000000..8702e70
--- /dev/null
+++ b/src/Config/Parser/JSONConfigParser.php
@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Config\Parser;
+
+use InvalidArgumentException;
+use Slim\Console\Config\Config;
+
+class JSONConfigParser implements ConfigParserInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public static function parse(string $path): Config
+    {
+        $contents = (string) file_get_contents($path);
+        $parsed = json_decode($contents, true);
+
+        if (json_last_error() !== JSON_ERROR_NONE) {
+            throw new InvalidArgumentException(
+                'Invalid JSON parsed from Slim Console configuration. ' . json_last_error_msg()
+            );
+        }
+
+        if (!is_array($parsed)) {
+            throw new InvalidArgumentException('Slim Console configuration should be an array.');
+        }
+
+        return Config::fromArray($parsed);
+    }
+}
diff --git a/src/Config/Parser/PHPConfigParser.php b/src/Config/Parser/PHPConfigParser.php
new file mode 100644
index 0000000..c6a13ff
--- /dev/null
+++ b/src/Config/Parser/PHPConfigParser.php
@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Config\Parser;
+
+use Slim\Console\Config\Config;
+use Slim\Console\Exception\CannotParseConfigException;
+
+class PHPConfigParser implements ConfigParserInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public static function parse(string $path): Config
+    {
+        $parsed = require $path;
+
+        if (!is_array($parsed)) {
+            throw new CannotParseConfigException('Slim Console configuration should be an array.');
+        }
+
+        return Config::fromArray($parsed);
+    }
+}
diff --git a/src/Exception/CannotParseConfigException.php b/src/Exception/CannotParseConfigException.php
new file mode 100644
index 0000000..c469703
--- /dev/null
+++ b/src/Exception/CannotParseConfigException.php
@@ -0,0 +1,17 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Exception;
+
+use Exception;
+
+class CannotParseConfigException extends Exception
+{
+}
diff --git a/src/Exception/CannotResolveConfigException.php b/src/Exception/CannotResolveConfigException.php
new file mode 100644
index 0000000..451c989
--- /dev/null
+++ b/src/Exception/CannotResolveConfigException.php
@@ -0,0 +1,21 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Console\Exception;
+
+use Exception;
+
+class CannotResolveConfigException extends Exception
+{
+    /**
+     * @var string
+     */
+    public $message = 'Cannot resolve Slim Console configuration file.';
+}
diff --git a/tests/AppTest.php b/tests/AppTest.php
new file mode 100644
index 0000000..40e8860
--- /dev/null
+++ b/tests/AppTest.php
@@ -0,0 +1,96 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console;
+
+use Prophecy\Argument;
+use Slim\Console\Config\Config;
+use Slim\Console\App;
+use Slim\Tests\Console\Mocks\MockCommand;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+class AppTest extends TestCase
+{
+    public function testDoRun(): void
+    {
+        $config = Config::fromDefaults();
+
+        $mockCommand = new MockCommand();
+
+        $app = new App($config);
+        $app->add($mockCommand);
+
+        $inputInterfaceProphecy = $this->prophesize(InputInterface::class);
+
+        $inputInterfaceProphecy
+            ->hasParameterOption(['--help', '-h'], true)
+            ->willReturn(false)
+            ->shouldBeCalledOnce();
+
+        $inputInterfaceProphecy
+            ->hasParameterOption(['--help', '-h'])
+            ->willReturn(true)
+            ->shouldBeCalledOnce();
+
+        $inputInterfaceProphecy
+            ->isInteractive()
+            ->willReturn(true)
+            ->shouldBeCalledOnce();
+
+        $inputInterfaceProphecy
+            ->hasArgument('command')
+            ->willReturn(false)
+            ->shouldBeCalledOnce();
+
+        $inputInterfaceProphecy
+            ->validate()
+            ->shouldBeCalledOnce();
+
+        $inputInterfaceProphecy
+            ->hasParameterOption(['--version', '-V'], true)
+            ->willReturn(false)
+            ->shouldBeCalledOnce();
+
+        $inputInterfaceProphecy
+            ->getFirstArgument()
+            ->willReturn(MockCommand::getDefaultName())
+            ->shouldBeCalledOnce();
+
+        $inputInterfaceProphecy
+            ->bind(Argument::any())
+            ->shouldBeCalledTimes(2);
+
+        $outputInterfaceProphecy = $this->prophesize(OutputInterface::class);
+
+        $outputInterfaceProphecy
+            ->writeln($app->getLongVersion())
+            ->shouldBeCalledOnce();
+
+        $outputInterfaceProphecy
+            ->writeln('')
+            ->shouldBeCalledOnce();
+
+        $outputInterfaceProphecy
+            ->writeln($mockCommand->getMockOutput())
+            ->shouldBeCalledOnce();
+
+        $app->doRun($inputInterfaceProphecy->reveal(), $outputInterfaceProphecy->reveal());
+    }
+
+    public function testGetConfig(): void
+    {
+        $config = Config::fromDefaults();
+
+        $app = new App($config);
+
+        $this->assertSame($config, $app->getConfig());
+    }
+}
diff --git a/tests/Command/AbstractCommandTest.php b/tests/Command/AbstractCommandTest.php
new file mode 100644
index 0000000..ef9116b
--- /dev/null
+++ b/tests/Command/AbstractCommandTest.php
@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console\Command;
+
+use RuntimeException;
+use Slim\Console\Config\Config;
+use Slim\Console\App;
+use Slim\Tests\Console\Mocks\MockCommand;
+use Slim\Tests\Console\TestCase;
+
+class AbstractCommandTest extends TestCase
+{
+    public function testGetConfig(): void
+    {
+        $config = Config::fromDefaults();
+
+        $mockCommand = new MockCommand();
+
+        $app = new App($config);
+        $app->add($mockCommand);
+
+        $this->assertSame($config, $mockCommand->getConfig());
+    }
+
+    public function testGetConfigThrowsRuntimeExceptionWithIncompatibleApp(): void
+    {
+        $mockCommand = new MockCommand();
+
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessage(
+            'Usage of the method `getConfig()` requires the parent application to be a Slim Console Application.'
+        );
+
+        $mockCommand->getConfig();
+    }
+}
diff --git a/tests/Config/ConfigResolverTest.php b/tests/Config/ConfigResolverTest.php
new file mode 100644
index 0000000..8472f7c
--- /dev/null
+++ b/tests/Config/ConfigResolverTest.php
@@ -0,0 +1,110 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console\Config;
+
+use Closure;
+use ReflectionMethod;
+use ReflectionProperty;
+use RuntimeException;
+use Slim\Console\Config\Config;
+use Slim\Console\Config\ConfigResolver;
+use Slim\Tests\Console\TestCase;
+
+class ConfigResolverTest extends TestCase
+{
+    public function supportedFormatsProvider(): array
+    {
+        return [
+            [ConfigResolver::FORMAT_PHP, function (string $path): ?array {
+                return require $path;
+            }],
+            [ConfigResolver::FORMAT_JSON, function (string $path): ?array {
+                return json_decode(file_get_contents($path), true);
+            }],
+        ];
+    }
+
+    public function testResolvePrioritizesEnvironment(): void
+    {
+        $this->setupEnvConfig();
+
+        $exampleJsonConfigPath = $this->getExampleConfigPath(ConfigResolver::FORMAT_JSON);
+        $configResolver = new ConfigResolver();
+
+        $config = $configResolver->resolve($exampleJsonConfigPath);
+
+        $this->assertSame($this->envParams['bootstrapDir'], $config->getBootstrapDir());
+        $this->assertSame($this->envParams['commandsDir'], $config->getCommandsDir());
+        $this->assertSame($this->envParams['indexDir'], $config->getIndexDir());
+        $this->assertSame($this->envParams['indexFile'], $config->getIndexFile());
+        $this->assertSame($this->envParams['sourceDir'], $config->getSourceDir());
+    }
+
+    /**
+     * @dataProvider supportedFormatsProvider
+     *
+     * @param string  $format
+     * @param Closure $parser
+     */
+    public function testAttemptResolvingConfigFromSupportedFormats(string $format, Closure $parser): void
+    {
+        $configPath = $this->getExampleConfigPath($format)
+            . DIRECTORY_SEPARATOR
+            . ConfigResolver::CONFIG_FILENAME . '.' . $format;
+        $example = $parser($configPath);
+
+        $exampleConfigPath = $this->getExampleConfigPath($format);
+        $configResolver = new ConfigResolver();
+
+        $config = $configResolver->resolve($exampleConfigPath);
+
+        $this->assertSame($example['bootstrapDir'], $config->getBootstrapDir());
+        $this->assertSame($example['commandsDir'], $config->getCommandsDir());
+        $this->assertSame($example['indexDir'], $config->getIndexDir());
+        $this->assertSame($example['indexFile'], $config->getIndexFile());
+        $this->assertSame($example['sourceDir'], $config->getSourceDir());
+    }
+
+    public function testAttemptParsingConfigFromFileThrowsRuntimeException(): void
+    {
+        $attemptParsingConfigFromFileMethod = new ReflectionMethod(
+            ConfigResolver::class,
+            'attemptParsingConfigFromFile'
+        );
+        $attemptParsingConfigFromFileMethod->setAccessible(true);
+
+        $invalidFormat = 'invalid';
+
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessage("Invalid configuration format `{$invalidFormat}`.");
+
+        $configResolver = new ConfigResolver();
+
+        $attemptParsingConfigFromFileMethod->invoke($configResolver, $this->examplesConfigBasePath, $invalidFormat);
+    }
+
+    public function testResolveFallbackOnDefaults(): void
+    {
+        $defaultsReflection = new ReflectionProperty(Config::class, 'defaults');
+        $defaultsReflection->setAccessible(true);
+
+        $defaults = $defaultsReflection->getValue();
+
+        $configResolver = new ConfigResolver();
+        $config = $configResolver->resolve($this->examplesConfigBasePath);
+
+        $this->assertSame($defaults['bootstrapDir'], $config->getBootstrapDir());
+        $this->assertSame($defaults['commandsDir'], $config->getCommandsDir());
+        $this->assertSame($defaults['indexDir'], $config->getIndexDir());
+        $this->assertSame($defaults['indexFile'], $config->getIndexFile());
+        $this->assertSame($defaults['sourceDir'], $config->getSourceDir());
+    }
+}
diff --git a/tests/Config/ConfigTest.php b/tests/Config/ConfigTest.php
new file mode 100644
index 0000000..90c9c3b
--- /dev/null
+++ b/tests/Config/ConfigTest.php
@@ -0,0 +1,112 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console\Config;
+
+use InvalidArgumentException;
+use ReflectionClass;
+use ReflectionProperty;
+use Slim\Console\Config\Config;
+use Slim\Tests\Console\TestCase;
+
+class ConfigTest extends TestCase
+{
+    public function testFromArray(): void
+    {
+        $bootstrapDir = 'customDir';
+        $commandsDir = 'customCommands';
+        $indexDir = 'customIndexDir';
+        $indexFile = 'custom.php';
+        $sourceDir = 'customSrc';
+
+        $config = Config::fromArray([
+            'bootstrapDir' => $bootstrapDir,
+            'commandsDir' => $commandsDir,
+            'indexDir' => $indexDir,
+            'indexFile' => $indexFile,
+            'sourceDir' => $sourceDir,
+        ]);
+
+        $this->assertSame($bootstrapDir, $config->getBootstrapDir());
+        $this->assertSame($commandsDir, $config->getCommandsDir());
+        $this->assertSame($indexDir, $config->getIndexDir());
+        $this->assertSame($indexFile, $config->getIndexFile());
+        $this->assertSame($sourceDir, $config->getSourceDir());
+    }
+
+    public function testFromEnvironment(): void
+    {
+        $this->setupEnvConfig();
+
+        $config = Config::fromEnvironment();
+
+        $this->assertSame($this->envParams['bootstrapDir'], $config->getBootstrapDir());
+        $this->assertSame($this->envParams['commandsDir'], $config->getCommandsDir());
+        $this->assertSame($this->envParams['indexDir'], $config->getIndexDir());
+        $this->assertSame($this->envParams['indexFile'], $config->getIndexFile());
+        $this->assertSame($this->envParams['sourceDir'], $config->getSourceDir());
+    }
+
+    public function testFromDefaults(): void
+    {
+        $defaultsReflection = new ReflectionProperty(Config::class, 'defaults');
+        $defaultsReflection->setAccessible(true);
+
+        $defaults = $defaultsReflection->getValue();
+        $config = Config::fromDefaults();
+
+        $this->assertSame($defaults['bootstrapDir'], $config->getBootstrapDir());
+        $this->assertSame($defaults['commandsDir'], $config->getCommandsDir());
+        $this->assertSame($defaults['indexDir'], $config->getIndexDir());
+        $this->assertSame($defaults['indexFile'], $config->getIndexFile());
+        $this->assertSame($defaults['sourceDir'], $config->getSourceDir());
+    }
+
+    public function invalidDataProvider(): array
+    {
+        return [
+            ['bootstrapDir', ''],
+            ['bootstrapDir', ' '],
+            ['commandsDir', ' '],
+            ['indexDir', ''],
+            ['indexDir', ' '],
+            ['indexFile', ''],
+            ['indexFile', ' '],
+            ['sourceDir', ''],
+            ['sourceDir', ' '],
+        ];
+    }
+
+    /**
+     * @dataProvider invalidDataProvider
+     *
+     * @param string $param
+     * @param string $value
+     */
+    public function testValidate(string $param, string $value): void
+    {
+        $configReflection = new ReflectionClass(Config::class);
+
+        $defaultsReflection = $configReflection->getProperty('defaults');
+        $defaultsReflection->setAccessible(true);
+
+        $defaults = $defaultsReflection->getValue();
+
+        $validateMethod = $configReflection->getMethod('validate');
+        $validateMethod->setAccessible(true);
+
+        $params = array_merge($defaults, [$param => $value]);
+
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage("`{$param}` must be a string.");
+
+        $validateMethod->invoke(null, $params);
+    }
+}
diff --git a/tests/Config/Parser/JSONConfigParserTest.php b/tests/Config/Parser/JSONConfigParserTest.php
new file mode 100644
index 0000000..c192dff
--- /dev/null
+++ b/tests/Config/Parser/JSONConfigParserTest.php
@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console\Config\Parser;
+
+use InvalidArgumentException;
+use Slim\Console\Config\ConfigResolver;
+use Slim\Console\Config\Parser\JSONConfigParser;
+use Slim\Tests\Console\TestCase;
+
+class JSONConfigParserTest extends TestCase
+{
+    public function invalidConfigurationProvider(): array
+    {
+        return [
+          ['invalid-format.json', 'Slim Console configuration should be an array.'],
+          ['invalid-syntax.json', 'Invalid JSON parsed from Slim Console configuration. Syntax error'],
+        ];
+    }
+
+    public function testParse(): void
+    {
+        $exampleJsonConfigPath = $this->getExampleConfigPath(ConfigResolver::FORMAT_JSON);
+        $jsonConfigPath = $exampleJsonConfigPath
+            . DIRECTORY_SEPARATOR
+            . ConfigResolver::CONFIG_FILENAME . '.' . ConfigResolver::FORMAT_JSON;
+        $jsonConfig = json_decode(file_get_contents($jsonConfigPath), true);
+
+        $config = JSONConfigParser::parse($jsonConfigPath);
+
+        $this->assertSame($jsonConfig['bootstrapDir'], $config->getBootstrapDir());
+        $this->assertSame($jsonConfig['commandsDir'], $config->getCommandsDir());
+        $this->assertSame($jsonConfig['indexDir'], $config->getIndexDir());
+        $this->assertSame($jsonConfig['indexFile'], $config->getIndexFile());
+        $this->assertSame($jsonConfig['sourceDir'], $config->getSourceDir());
+    }
+
+    /**
+     * @dataProvider invalidConfigurationProvider
+     *
+     * @param string $fileName
+     * @param string $expectedExceptionMessage
+     */
+    public function testParseThrowsInvalidArgumentException(string $fileName, string $expectedExceptionMessage): void
+    {
+        $invalidJsonConfigPath = $this->examplesConfigBasePath
+            . DIRECTORY_SEPARATOR . 'invalid-json'
+            . DIRECTORY_SEPARATOR . $fileName;
+
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage($expectedExceptionMessage);
+
+        JSONConfigParser::parse($invalidJsonConfigPath);
+    }
+}
diff --git a/tests/Config/Parser/PHPConfigParserTest.php b/tests/Config/Parser/PHPConfigParserTest.php
new file mode 100644
index 0000000..27e2bb6
--- /dev/null
+++ b/tests/Config/Parser/PHPConfigParserTest.php
@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console\Config\Parser;
+
+use Slim\Console\Config\ConfigResolver;
+use Slim\Console\Config\Parser\PHPConfigParser;
+use Slim\Console\Exception\CannotParseConfigException;
+use Slim\Tests\Console\TestCase;
+
+class PHPConfigParserTest extends TestCase
+{
+    public function testParse(): void
+    {
+        $exampleJsonConfigPath = $this->getExampleConfigPath(ConfigResolver::FORMAT_PHP);
+        $phpConfigPath = $exampleJsonConfigPath
+            . DIRECTORY_SEPARATOR
+            . ConfigResolver::CONFIG_FILENAME . '.' . ConfigResolver::FORMAT_PHP;
+        $phpConfig = require $phpConfigPath;
+
+        $config = PHPConfigParser::parse($phpConfigPath);
+
+        $this->assertSame($phpConfig['bootstrapDir'], $config->getBootstrapDir());
+        $this->assertSame($phpConfig['commandsDir'], $config->getCommandsDir());
+        $this->assertSame($phpConfig['indexDir'], $config->getIndexDir());
+        $this->assertSame($phpConfig['indexFile'], $config->getIndexFile());
+        $this->assertSame($phpConfig['sourceDir'], $config->getSourceDir());
+    }
+
+    public function testParseThrowsExceptionWithInvalidConfigFormat(): void
+    {
+        $invalidJsonConfigPath = $this->examplesConfigBasePath
+            . DIRECTORY_SEPARATOR . 'invalid-php'
+            . DIRECTORY_SEPARATOR . 'invalid-format.php';
+
+        $this->expectException(CannotParseConfigException::class);
+        $this->expectExceptionMessage('Slim Console configuration should be an array.');
+
+        PHPConfigParser::parse($invalidJsonConfigPath);
+    }
+}
diff --git a/tests/Mocks/MockCommand.php b/tests/Mocks/MockCommand.php
new file mode 100644
index 0000000..b1bfc72
--- /dev/null
+++ b/tests/Mocks/MockCommand.php
@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console\Mocks;
+
+use Slim\Console\Command\AbstractCommand;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+class MockCommand extends AbstractCommand
+{
+    /**
+     * @var string
+     */
+    protected static $defaultName = 'mock';
+
+    /**
+     * @var string
+     */
+    private $output = 'output';
+
+    /**
+     * @param InputInterface  $input
+     * @param OutputInterface $output
+     * @return int
+     */
+    protected function execute(InputInterface $input, OutputInterface $output)
+    {
+        $output->writeln($this->getMockOutput());
+        return 1;
+    }
+
+    /**
+     * @return string
+     */
+    public function getMockOutput(): string
+    {
+        return $this->output;
+    }
+}
diff --git a/tests/TestCase.php b/tests/TestCase.php
new file mode 100644
index 0000000..ac97c02
--- /dev/null
+++ b/tests/TestCase.php
@@ -0,0 +1,61 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim\Tests\Console;
+
+use PHPUnit\Framework\TestCase as PHPUnitTestCase;
+use Slim\Console\Config\Config;
+
+abstract class TestCase extends PhpUnitTestCase
+{
+    public function setUp(): void
+    {
+        putenv(Config::SLIM_CONSOLE_BOOTSTRAP_DIR . '=');
+        putenv(Config::SLIM_CONSOLE_COMMANDS_DIR . '=');
+        putenv(Config::SLIM_CONSOLE_INDEX_DIR . '=');
+        putenv(Config::SLIM_CONSOLE_INDEX_FILE . '=');
+        putenv(Config::SLIM_CONSOLE_SOURCE_DIR . '=');
+    }
+
+    /**
+     * @var string
+     */
+    protected $examplesConfigBasePath = __DIR__ . DIRECTORY_SEPARATOR . 'examples';
+
+    /**
+     * @param string $format
+     *
+     * @return string
+     */
+    protected function getExampleConfigPath(string $format): string
+    {
+        return $this->examplesConfigBasePath . DIRECTORY_SEPARATOR . $format;
+    }
+
+    /**
+     * @var string[]
+     */
+    protected $envParams = [
+        'bootstrapDir' => 'envCustomDir',
+        'commandsDir' => 'envCustomCommands',
+        'indexDir' => 'envCustomIndexDir',
+        'indexFile' => 'envCustom.php',
+        'sourceDir' => 'envCustomSrc',
+    ];
+
+    protected function setupEnvConfig(): void
+    {
+        putenv(Config::SLIM_CONSOLE_BOOTSTRAP_DIR . '=' . $this->envParams['bootstrapDir']);
+        putenv(Config::SLIM_CONSOLE_COMMANDS_DIR . '=' . $this->envParams['commandsDir']);
+        putenv(Config::SLIM_CONSOLE_INDEX_DIR . '=' . $this->envParams['indexDir']);
+        putenv(Config::SLIM_CONSOLE_INDEX_FILE . '=' . $this->envParams['indexFile']);
+        putenv(Config::SLIM_CONSOLE_SOURCE_DIR . '=' . $this->envParams['sourceDir']);
+    }
+}
diff --git a/tests/examples/invalid-json/invalid-format.json b/tests/examples/invalid-json/invalid-format.json
new file mode 100644
index 0000000..50a269a
--- /dev/null
+++ b/tests/examples/invalid-json/invalid-format.json
@@ -0,0 +1 @@
+"invalid"
diff --git a/tests/examples/invalid-json/invalid-syntax.json b/tests/examples/invalid-json/invalid-syntax.json
new file mode 100644
index 0000000..cee1564
--- /dev/null
+++ b/tests/examples/invalid-json/invalid-syntax.json
@@ -0,0 +1,3 @@
+{
+    invalid: 'json',
+}
diff --git a/tests/examples/invalid-php/invalid-format.php b/tests/examples/invalid-php/invalid-format.php
new file mode 100644
index 0000000..ce6a0b9
--- /dev/null
+++ b/tests/examples/invalid-php/invalid-format.php
@@ -0,0 +1,11 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+return "invalid";
diff --git a/tests/examples/json/slim-console.config.json b/tests/examples/json/slim-console.config.json
new file mode 100644
index 0000000..deae10c
--- /dev/null
+++ b/tests/examples/json/slim-console.config.json
@@ -0,0 +1,7 @@
+{
+    "bootstrapDir": "customBootstrapDir",
+    "commandsDir": "customCommandsDir",
+    "indexDir": "customIndexDir",
+    "indexFile": "customIndexFile.php",
+    "sourceDir": "customSourceDir"
+}
diff --git a/tests/examples/php/slim-console.config.php b/tests/examples/php/slim-console.config.php
new file mode 100644
index 0000000..68868fa
--- /dev/null
+++ b/tests/examples/php/slim-console.config.php
@@ -0,0 +1,17 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim-Console/blob/0.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+return [
+    'bootstrapDir' => 'customBootstrapDir',
+    'commandsDir' => 'customCommandsDir',
+    'indexDir' => 'customIndexDir',
+    'indexFile' => 'customIndexFile.php',
+    'sourceDir' => 'customSourceDir',
+];