diff --git a/composer.json b/composer.json
index 96cdc3f..781043a 100644
--- a/composer.json
+++ b/composer.json
@@ -46,6 +46,9 @@
             "main": "2.x-dev"
         }
     },
+    "bin": [
+        "depanno"
+    ],
     "archive": {
         "exclude": [
             ".github",
diff --git a/depanno b/depanno
new file mode 100644
index 0000000..9bcb689
--- /dev/null
+++ b/depanno
@@ -0,0 +1,45 @@
+#!/usr/bin/env php
+<?php
+
+/**
+ * @copyright 2021 Navarr Barnier. All Rights Reserved.
+ */
+
+declare(strict_types=1);
+
+use Navarr\Depends\Controller\CliApplication;
+
+if (version_compare('7.1.0', PHP_VERSION, '>')) {
+    fwrite(
+        STDERR,
+        "This version of DepAnno requires PHP 7.1.0 or greater." . PHP_EOL .
+        "You are currently using PHP " . PHP_VERSION . PHP_EOL
+    );
+    die(1);
+}
+
+if (!ini_get('date.timezone')) {
+    ini_set('date.timezone', 'UTC');
+}
+
+$found = false;
+foreach (
+    [
+        __DIR__ . '/../../autoload.php',
+        __DIR__ . '/../vendor/autoload.php',
+        __DIR__ . '/vendor/autoload.php',
+    ] as $autoload
+) {
+    if (file_exists($autoload)) {
+        require_once($autoload);
+        $found = true;
+        break;
+    }
+}
+
+if (!$found) {
+    fwrite(STDERR, "You must install DepAnno using Composer");
+    die(1);
+}
+
+die(CliApplication::execute());
diff --git a/src/Controller/CliApplication.php b/src/Controller/CliApplication.php
new file mode 100644
index 0000000..4a3a73b
--- /dev/null
+++ b/src/Controller/CliApplication.php
@@ -0,0 +1,25 @@
+<?php
+
+/**
+ * @copyright 2021 Navarr Barnier. All Rights Reserved.
+ */
+
+declare(strict_types=1);
+
+namespace Navarr\Depends\Controller;
+
+use Navarr\Attribute\Dependency;
+use Symfony\Component\Console\Application;
+
+#[Dependency('symfony/console', '^5', 'Creates a Symfony Application')]
+class CliApplication
+{
+    private const VERSION = '2.1.0';
+
+    public static function execute(): int
+    {
+        $application = new Application('DepAnno', static::VERSION);
+        $application->add(new WhyBlockCommandController());
+        return $application->run();
+    }
+}
diff --git a/src/Controller/WhyBlockCommandController.php b/src/Controller/WhyBlockCommandController.php
new file mode 100644
index 0000000..4421c9e
--- /dev/null
+++ b/src/Controller/WhyBlockCommandController.php
@@ -0,0 +1,158 @@
+<?php
+
+/**
+ * @copyright 2021 Navarr Barnier. All Rights Reserved.
+ */
+
+declare(strict_types=1);
+
+namespace Navarr\Depends\Controller;
+
+use DI\ContainerBuilder;
+use InvalidArgumentException;
+use Navarr\Attribute\Dependency;
+use Navarr\Depends\Command\WhyBlockCommand;
+use Navarr\Depends\Command\WhyBlockCommand\CsvOutputHandler;
+use Navarr\Depends\Command\WhyBlockCommand\JsonOutputHandler;
+use Navarr\Depends\Command\WhyBlockCommand\OutputHandlerInterface;
+use Navarr\Depends\Command\WhyBlockCommand\StandardOutputHandler;
+use Navarr\Depends\Command\WhyBlockCommand\XmlOutputHandler;
+use Navarr\Depends\IssueHandler\FailOnIssueHandler;
+use Navarr\Depends\IssueHandler\IssueHandlerInterface;
+use Navarr\Depends\IssueHandler\NotifyOnIssueHandler;
+use Navarr\Depends\Parser\AstParser;
+use Navarr\Depends\Parser\LegacyParser;
+use Navarr\Depends\Parser\ParserInterface;
+use Navarr\Depends\Parser\ParserPool;
+use Navarr\Depends\Proxy\StdOutWriter;
+use Navarr\Depends\Proxy\WriterInterface;
+use Navarr\Depends\ScopeDeterminer\ComposerScopeDeterminer;
+use Navarr\Depends\ScopeDeterminer\DirectoryScopeDeterminer;
+use Navarr\Depends\ScopeDeterminer\PhpFileFinder;
+use Navarr\Depends\ScopeDeterminer\ScopeDeterminerInterface;
+use Psr\Container\ContainerInterface;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+
+use function DI\autowire;
+use function DI\create;
+
+class WhyBlockCommandController extends Command
+{
+    private const LEGACY_ANNOTATION = 'include-legacy-annotations';
+    private const FAIL_ON_ERROR = 'fail-on-error';
+    private const OUTPUT_FORMAT = 'format';
+
+    private const FORMAT_TEXT = 'text';
+    private const FORMAT_CSV = 'csv';
+    private const FORMAT_JSON = 'json';
+    private const FORMAT_XML = 'xml';
+
+    private const ACCEPTABLE_FORMATS = [
+        self::FORMAT_CSV,
+        self::FORMAT_TEXT,
+        self::FORMAT_JSON,
+        self::FORMAT_XML,
+    ];
+
+    private const FORMAT_MAPPER = [
+        self::FORMAT_CSV => CsvOutputHandler::class,
+        self::FORMAT_TEXT => StandardOutputHandler::class,
+        self::FORMAT_JSON => JsonOutputHandler::class,
+        self::FORMAT_XML => XmlOutputHandler::class,
+    ];
+
+    // phpcs:disable Generic.Files.LineLength.TooLong -- Attribute support pre PHP 8
+    #[Dependency('symfony/console', '^5', 'Command\'s setName, addArgument and addOption methods as well as InputArgument\'s constants of REQUIRED and VALUE_NONE')]
+    #[Dependency('php-di/php-di', '^6', 'DI\ContainerBuilder::addDefinitions and the existence of the DI\autowire function')]
+    // phpcs:enable Generic.Files.LineLength.TooLong
+    protected function configure(): void
+    {
+        $this->setName('why-block')
+            ->addArgument('package', InputArgument::REQUIRED, 'Package to inspect')
+            ->addArgument('version', InputArgument::REQUIRED, 'Version you want to update it to')
+            ->addArgument('directory', InputArgument::REQUIRED, 'Directory to search in')
+            ->addOption(
+                self::OUTPUT_FORMAT,
+                ['f'],
+                InputOption::VALUE_OPTIONAL,
+                'Format to output results in.  Accepted values: text, csv, json, xml',
+                'text'
+            )
+            ->addOption(
+                self::FAIL_ON_ERROR,
+                ['e'],
+                InputOption::VALUE_NONE,
+                'Immediately fail on parsing errors'
+            )
+            ->addOption(
+                self::LEGACY_ANNOTATION,
+                ['l'],
+                InputOption::VALUE_NONE,
+                'Include old @dependency/@composerDependency annotations in search'
+            );
+    }
+
+    #[Dependency('symfony/console', '^5', 'InputInterface::getOption and OutputInterface::writeln')]
+    protected function execute(
+        InputInterface $input,
+        OutputInterface $output
+    ): int {
+        $packageToSearchFor = $input->getArgument('package');
+        $versionToCompareTo = $input->getArgument('version');
+        $directory = $input->getArgument('directory');
+        $outputFormat = $input->getOption(self::OUTPUT_FORMAT);
+
+        if (!is_string($directory)) {
+            throw new InvalidArgumentException('Only one directory is allowed');
+        }
+        if (!is_string($packageToSearchFor)) {
+            throw new InvalidArgumentException('Only one package is allowed');
+        }
+        if (!is_string($versionToCompareTo)) {
+            throw new InvalidArgumentException('Only one version is allowed');
+        }
+        if (!is_string($outputFormat)) {
+            throw new InvalidArgumentException('Only one output format is allowed');
+        }
+
+        $outputFormat = strtolower($outputFormat);
+        if (!in_array($outputFormat, static::ACCEPTABLE_FORMATS)) {
+            $outputFormat = 'text';
+        }
+
+        $containerBuilder = new ContainerBuilder();
+        $containerBuilder->addDefinitions(
+            [
+                InputInterface::class => $input,
+                OutputInterface::class => $output,
+                IssueHandlerInterface::class => $input->getOption(static::FAIL_ON_ERROR)
+                    ? FailOnIssueHandler::class
+                    : NotifyOnIssueHandler::class,
+                ParserInterface::class => static function (ContainerInterface $container) use ($input) {
+                    $parsers = [$container->get(AstParser::class)];
+                    if ($input->getOption(static::LEGACY_ANNOTATION)) {
+                        $parsers[] = $container->get(LegacyParser::class);
+                    }
+                    return new ParserPool($parsers);
+                },
+                WriterInterface::class => autowire(StdOutWriter::class),
+                ScopeDeterminerInterface::class => static function (ContainerInterface $container) use ($directory) {
+                    return new DirectoryScopeDeterminer(
+                        $container->get(PhpFileFinder::class),
+                        $directory
+                    );
+                },
+                OutputHandlerInterface::class => autowire(static::FORMAT_MAPPER[$outputFormat]),
+            ]
+        );
+        $container = $containerBuilder->build();
+
+        /** @var WhyBlockCommand $command */
+        $command = $container->get(WhyBlockCommand::class);
+        return $command->execute($packageToSearchFor, $versionToCompareTo);
+    }
+}
diff --git a/src/ScopeDeterminer/ComposerScopeDeterminer.php b/src/ScopeDeterminer/ComposerScopeDeterminer.php
index 7af77d9..507b2f3 100644
--- a/src/ScopeDeterminer/ComposerScopeDeterminer.php
+++ b/src/ScopeDeterminer/ComposerScopeDeterminer.php
@@ -26,20 +26,20 @@ class ComposerScopeDeterminer implements ScopeDeterminerInterface
     /** @var Composer */
     private $composer;
 
-    /** @var PhpFileDeterminer */
-    private $phpFileDeterminer;
+    /** @var PhpFileFinder */
+    private $phpFileFinder;
 
     /** @var int */
     private $scope;
 
     public function __construct(
         Composer $composer,
-        PhpFileDeterminer $phpFileDeterminer,
+        PhpFileFinder $phpFileFinder,
         #[ExpectedValues(valuesFromClass: ComposerScopeDeterminer::class)]
         int $scope = self::SCOPE_PROJECT_ONLY
     ) {
         $this->composer = $composer;
-        $this->phpFileDeterminer = $phpFileDeterminer;
+        $this->phpFileFinder = $phpFileFinder;
         $this->scope = $scope;
     }
 
@@ -133,40 +133,10 @@ private function getAllFilesForAutoload(
                     continue;
                 }
                 if (is_dir($realDir)) {
-                    $results = $this->getAllPhpFiles($realDir, $results);
+                    $results = $this->phpFileFinder->findAll($dir, $results);
                 }
             }
         }
         return $results;
     }
-
-    /**
-     * Find all PHP files by recursively searching a directory
-     *
-     * @param string $dir Directory to search recursively
-     * @param string[] $results Array of file paths to merge with
-     * @return string[] File paths
-     */
-    private function getAllPhpFiles(string $dir, array $results = []): array
-    {
-        $files = scandir($dir);
-        if ($files === false) {
-            return $results;
-        }
-
-        foreach ($files as $value) {
-            $path = realpath($dir . DIRECTORY_SEPARATOR . $value);
-            if ($path === false) {
-                continue;
-            }
-
-            if (is_file($path) && $this->phpFileDeterminer->isPhp($path)) {
-                $results[] = $path;
-            } elseif (is_dir($path) && !in_array($value, ['.', '..'])) {
-                $results = $this->getAllPhpFiles($path, $results);
-            }
-        }
-
-        return $results;
-    }
 }
diff --git a/src/ScopeDeterminer/DirectoryScopeDeterminer.php b/src/ScopeDeterminer/DirectoryScopeDeterminer.php
new file mode 100644
index 0000000..faabe68
--- /dev/null
+++ b/src/ScopeDeterminer/DirectoryScopeDeterminer.php
@@ -0,0 +1,29 @@
+<?php
+
+/**
+ * @copyright 2021 Navarr Barnier. All Rights Reserved.
+ */
+
+declare(strict_types=1);
+
+namespace Navarr\Depends\ScopeDeterminer;
+
+class DirectoryScopeDeterminer implements ScopeDeterminerInterface
+{
+    /** @var string */
+    private $directory;
+
+    /** @var PhpFileFinder */
+    private $phpfileFinder;
+
+    public function __construct(PhpFileFinder $phpfileFinder, string $directory = '.')
+    {
+        $this->directory = $directory;
+        $this->phpfileFinder = $phpfileFinder;
+    }
+
+    public function getFiles(): array
+    {
+        return $this->phpfileFinder->findAll($this->directory);
+    }
+}
diff --git a/src/ScopeDeterminer/PhpFileFinder.php b/src/ScopeDeterminer/PhpFileFinder.php
new file mode 100644
index 0000000..9aca361
--- /dev/null
+++ b/src/ScopeDeterminer/PhpFileFinder.php
@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * @copyright 2021 Navarr Barnier. All Rights Reserved.
+ */
+
+declare(strict_types=1);
+
+namespace Navarr\Depends\ScopeDeterminer;
+
+class PhpFileFinder
+{
+    /** @var PhpFileDeterminer */
+    private $phpFileDeterminer;
+
+    public function __construct(PhpFileDeterminer $phpFileDeterminer)
+    {
+        $this->phpFileDeterminer = $phpFileDeterminer;
+    }
+
+    /**
+     * Find all PHP files by recursively searching a directory
+     *
+     * @param string $dir Directory to search recursively
+     * @param string[] $results Array of file paths to merge with
+     * @return string[] File paths
+     */
+    public function findAll(string $dir, array $results = []): array
+    {
+        // Directories is ever expanding by the loop.  We do this instead of recursion b/c I have an unhealthy fear
+        // of recursion limits
+        $directories = [$dir];
+        for ($i = 0; $i < count($directories); ++$i) {
+            $files = scandir($directories[$i]);
+            if ($files !== false) {
+                foreach ($files as $value) {
+                    $path = realpath($directories[$i] . DIRECTORY_SEPARATOR . $value);
+                    if ($path === false) {
+                        continue;
+                    }
+
+                    if (is_file($path) && $this->phpFileDeterminer->isPhp($path)) {
+                        $results[] = $path;
+                    } elseif (is_dir($path) && !in_array($value, ['.', '..'])) {
+                        $directories[] = $path;
+                    }
+                }
+            }
+        }
+
+        return $results;
+    }
+}
diff --git a/tests/ScopeDeterminer/DirectoryScopeDeterminerTest.php b/tests/ScopeDeterminer/DirectoryScopeDeterminerTest.php
new file mode 100644
index 0000000..f618b5a
--- /dev/null
+++ b/tests/ScopeDeterminer/DirectoryScopeDeterminerTest.php
@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @copyright 2021 Navarr Barnier. All Rights Reserved.
+ */
+
+declare(strict_types=1);
+
+namespace Navarr\Depends\Test\ScopeDeterminer;
+
+use Navarr\Depends\ScopeDeterminer\DirectoryScopeDeterminer;
+use Navarr\Depends\ScopeDeterminer\PhpFileFinder;
+use PHPUnit\Framework\TestCase;
+
+class DirectoryScopeDeterminerTest extends TestCase
+{
+    public function testDirectoryIsGivenToPhpFileFinder(): void
+    {
+        $dir = uniqid();
+        $finder = $this->createMock(PhpFileFinder::class);
+        $finder->expects($this->once())
+            ->method('findAll')
+            ->with($dir)
+            ->willReturn([]);
+
+        $determiner = new DirectoryScopeDeterminer($finder, $dir);
+        $determiner->getFiles();
+    }
+
+    public function testResultOfPhpFileFinderIsProvidedBack(): void
+    {
+        $results = [
+            uniqid(),
+            uniqid()
+        ];
+
+        $finder = $this->createMock(PhpFileFinder::class);
+        $finder->method('findAll')
+            ->willReturn($results);
+
+        $determiner = new DirectoryScopeDeterminer($finder, uniqid());
+        $this->assertEquals($results, $determiner->getFiles());
+    }
+}
diff --git a/tests/ScopeDeterminer/PhpFileFinderTest.php b/tests/ScopeDeterminer/PhpFileFinderTest.php
new file mode 100644
index 0000000..8042e4b
--- /dev/null
+++ b/tests/ScopeDeterminer/PhpFileFinderTest.php
@@ -0,0 +1,51 @@
+<?php
+
+/**
+ * @copyright 2021 Navarr Barnier. All Rights Reserved.
+ */
+
+declare(strict_types=1);
+
+namespace Navarr\Depends\Test\ScopeDeterminer;
+
+use DI\Container;
+use Navarr\Depends\ScopeDeterminer\PhpFileFinder;
+use PHPUnit\Framework\TestCase;
+
+class PhpFileFinderTest extends TestCase
+{
+    public function testFindAll()
+    {
+        $directory = implode(
+            DIRECTORY_SEPARATOR,
+            [
+                __DIR__,
+                '..',
+                '_data',
+                'phpFileFinder',
+            ]
+        );
+
+        $files = array_map(
+            'realpath',
+            [
+                $directory . DIRECTORY_SEPARATOR . 'file1.php',
+                $directory . DIRECTORY_SEPARATOR . 'recursion1/file4.php',
+                $directory . DIRECTORY_SEPARATOR . 'recursion1/anotherFile.php',
+                $directory . DIRECTORY_SEPARATOR . 'recursion1/recursion2/file3.php',
+                $directory . DIRECTORY_SEPARATOR . 'recursion1/recursion2/recursion3/file2.php',
+            ]
+        );
+
+        $container = new Container();
+        $finder = $container->get(PhpFileFinder::class);
+        $results = $finder->findAll($directory);
+
+        $this->assertIsArray($results);
+        $this->assertCount(5, $results);
+
+        foreach ($files as $file) {
+            $this->assertContains($file, $results);
+        }
+    }
+}
diff --git a/tests/_data/phpFileFinder/file1.php b/tests/_data/phpFileFinder/file1.php
new file mode 100644
index 0000000..8767608
--- /dev/null
+++ b/tests/_data/phpFileFinder/file1.php
@@ -0,0 +1,3 @@
+<?php
+
+// a php file in the base directory searched
diff --git a/tests/_data/phpFileFinder/recursion1/anotherFile.php b/tests/_data/phpFileFinder/recursion1/anotherFile.php
new file mode 100644
index 0000000..b066f25
--- /dev/null
+++ b/tests/_data/phpFileFinder/recursion1/anotherFile.php
@@ -0,0 +1,3 @@
+<?php
+
+// another file in the first directory deep
diff --git a/tests/_data/phpFileFinder/recursion1/file4.php b/tests/_data/phpFileFinder/recursion1/file4.php
new file mode 100644
index 0000000..c3a3368
--- /dev/null
+++ b/tests/_data/phpFileFinder/recursion1/file4.php
@@ -0,0 +1,3 @@
+<?php
+
+// a file one directory deep
diff --git a/tests/_data/phpFileFinder/recursion1/recursion2/file3.php b/tests/_data/phpFileFinder/recursion1/recursion2/file3.php
new file mode 100644
index 0000000..e050e9d
--- /dev/null
+++ b/tests/_data/phpFileFinder/recursion1/recursion2/file3.php
@@ -0,0 +1,3 @@
+<?php
+
+// a file two directories deep
diff --git a/tests/_data/phpFileFinder/recursion1/recursion2/recursion3/file2.php b/tests/_data/phpFileFinder/recursion1/recursion2/recursion3/file2.php
new file mode 100644
index 0000000..3374111
--- /dev/null
+++ b/tests/_data/phpFileFinder/recursion1/recursion2/recursion3/file2.php
@@ -0,0 +1,3 @@
+<?php
+
+// a file several directories deep