From 51e36040746f0d40b3146fd8e72ac8acec065075 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 11:37:57 -0300
Subject: [PATCH 01/22] Chore

---
 composer.json  |   3 +-
 src/Monkey.php | 153 ++++++++++++++++++++++++++++++++++++++-----------
 2 files changed, 123 insertions(+), 33 deletions(-)

diff --git a/composer.json b/composer.json
index bc332ec..8ebdd53 100644
--- a/composer.json
+++ b/composer.json
@@ -10,7 +10,8 @@
   },
   "require": {
     "php": "^8.4",
-    "ext-readline": "*"
+    "ext-readline": "*",
+    "symfony/console": "^7.2"
   },
   "autoload": {
     "psr-4": {
diff --git a/src/Monkey.php b/src/Monkey.php
index d3a90d1..7549b01 100644
--- a/src/Monkey.php
+++ b/src/Monkey.php
@@ -12,12 +12,20 @@
 use Monkey\Parser\Parser;
 use Monkey\Parser\ProgramParser;
 use RuntimeException;
+use Symfony\Component\Console\Formatter\OutputFormatterStyle;
+use Symfony\Component\Console\Helper\Table;
+use Symfony\Component\Console\Helper\TableStyle;
+use Symfony\Component\Console\Output\ConsoleOutput;
+use Symfony\Component\Console\Output\OutputInterface;
 use Throwable;
 
 use function count;
 
+use function in_array;
+use function sprintf;
+
 use const PHP_EOL;
-use const STDERR;
+use const STR_PAD_RIGHT;
 
 final class Monkey
 {
@@ -25,11 +33,27 @@ final class Monkey
 
     private readonly Environment $environment;
 
+    private readonly OutputInterface $output;
+
     private bool $debugMode = false;
 
+    private bool $showStats = false;
+
+    private readonly float $startTime;
+
+    private readonly int $startMemory;
+
     public function __construct()
     {
         $this->environment = new Environment();
+        $this->startTime = microtime(true);
+        $this->startMemory = memory_get_usage();
+
+        $this->output = new ConsoleOutput();
+        $this->output->getFormatter()->setStyle('title', new OutputFormatterStyle('white', null, ['bold']));
+        $this->output->getFormatter()->setStyle('memory', new OutputFormatterStyle('green'));
+        $this->output->getFormatter()->setStyle('peak', new OutputFormatterStyle('yellow'));
+        $this->output->getFormatter()->setStyle('time', new OutputFormatterStyle('blue'));
     }
 
     /**
@@ -41,22 +65,111 @@ public function run(array $argv): int
             return $this->showHelp();
         }
 
+        if (in_array('--debug', $argv)) {
+            $this->debugMode = true;
+            $argv = array_values(array_filter($argv, fn ($arg): bool => $arg !== '--debug'));
+        }
+
+        if (in_array('--stats', $argv)) {
+            $this->showStats = true;
+            $argv = array_values(array_filter($argv, fn ($arg): bool => $arg !== '--stats'));
+        }
+
         try {
-            return match ($argv[1]) {
+            // If we removed --debug and no other args remain, show help
+            if (count($argv) <= 1) {
+                return $this->showHelp();
+            }
+
+            $result = match ($argv[1]) {
                 'repl' => $this->startRepl(),
                 'run' => $this->runFile($argv[2] ?? null),
                 '--version', '-v' => $this->showVersion(),
                 '--help', '-h' => $this->showHelp(),
-                '--debug' => $this->enableDebugMode(),
                 default => $this->showHelp(),
             };
+
+            if ($this->showStats) {
+                $this->printPerformanceStats();
+            }
+
+            return $result;
         } catch (Throwable $throwable) {
             $this->writeError($throwable->getMessage());
 
+            if ($this->showStats) {
+                $this->printPerformanceStats();
+            }
+
             return 1;
         }
     }
 
+    private function printPerformanceStats(): void
+    {
+        $timeEnd = microtime(true);
+        $memEnd = memory_get_usage();
+        $memUsed = $memEnd - $this->startMemory;
+        $peakMem = memory_get_peak_usage(true);
+        $timeTaken = $timeEnd - $this->startTime;
+
+        $this->output->writeln('');
+        $this->output->writeln('');
+        $this->output->writeln('<title>Performance Statistics</title>');
+
+        $tableStyle = new TableStyle();
+        $tableStyle
+            ->setHorizontalBorderChars('-')
+            ->setVerticalBorderChars('|')
+            ->setCrossingChars('+', '+', '+', '+', '+', '+', '+', '+', '+')
+            ->setPadType(STR_PAD_RIGHT);
+
+        $table = new Table($this->output);
+        $table->setStyle($tableStyle);
+
+        $table->setRows([
+            ['Memory used', "<memory>{$this->formatBytes($memUsed)}</memory>"],
+            ['Peak memory', "<peak>{$this->formatBytes($peakMem)}</peak>"],
+            ['Time taken', '<time>' . number_format($timeTaken, 6) . ' seconds</time>'],
+        ]);
+
+        $table->render();
+
+        $this->output->writeln('');
+    }
+
+    private function writeOutput(MonkeyObject $result): void
+    {
+        // Skip output for NullObject unless in debug mode
+        if ($result instanceof NullObject && !$this->debugMode) {
+            return;
+        }
+
+        if ($this->debugMode) {
+            $class = $result::class;
+            $this->output->write("<comment>{$class}:</comment> ");
+        }
+
+        $this->output->writeln($result->inspect());
+    }
+
+    private function writeError(string $message): void
+    {
+        $this->output->writeln("<error>Error: {$message}</error>");
+    }
+
+    private function formatBytes(int $bytes): string
+    {
+        $units = ['B', 'KB', 'MB', 'GB'];
+        $bytes = max($bytes, 0);
+        $pow = floor(($bytes ? log($bytes) : 0) / log(1024));
+        $pow = min($pow, count($units) - 1);
+
+        $bytes /= (1 << (10 * $pow));
+
+        return sprintf('%.2f %s', $bytes, $units[$pow]);
+    }
+
     private function startRepl(): int
     {
         $this->showWelcomeBanner();
@@ -137,8 +250,11 @@ private function handleSpecialCommand(string $input): bool
 
     private function handleQuit(): bool
     {
-        echo 'Goodbye!' . PHP_EOL;
+        if ($this->showStats) {
+            $this->printPerformanceStats();
+        }
 
+        echo 'Goodbye!' . PHP_EOL;
         exit(0);
     }
 
@@ -160,7 +276,6 @@ private function handleHelp(): bool
     private function handleClear(): bool
     {
         system('clear');
-
         $this->showWelcomeBanner();
 
         return true;
@@ -169,7 +284,6 @@ private function handleClear(): bool
     private function handleDebugToggle(): bool
     {
         $this->debugMode = !$this->debugMode;
-
         echo 'Debug mode: ' . ($this->debugMode ? 'Enabled' : 'Disabled') . PHP_EOL;
 
         return true;
@@ -190,25 +304,6 @@ private function readInput(): string | false
         return readline("\n➜ ");
     }
 
-    private function writeOutput(MonkeyObject $result): void
-    {
-        // Skip output for NullObject unless in debug mode
-        if ($result instanceof NullObject && !$this->debugMode) {
-            return;
-        }
-
-        if ($this->debugMode) {
-            echo $result::class . ': ';
-        }
-
-        echo $result->inspect() . PHP_EOL;
-    }
-
-    private function writeError(string $message): void
-    {
-        fwrite(STDERR, 'Error: ' . $message . PHP_EOL);
-    }
-
     private function showVersion(): int
     {
         echo 'Monkey Programming Language v' . self::VERSION . PHP_EOL;
@@ -227,6 +322,7 @@ private function showHelp(): int
             --version, -v     Show version information
             --help, -h        Show this help message
             --debug           Enable debug mode
+            --stats           Show performance statistics
 
         Examples:
             monkey repl
@@ -235,11 +331,4 @@ private function showHelp(): int
 
         return 0;
     }
-
-    private function enableDebugMode(): int
-    {
-        $this->debugMode = true;
-
-        return $this->startRepl();
-    }
 }

From d36cc463ba032b652e760b89813780e323a69c26 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 11:42:28 -0300
Subject: [PATCH 02/22] Chore

---
 src/Monkey.php | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/src/Monkey.php b/src/Monkey.php
index 7549b01..9336d71 100644
--- a/src/Monkey.php
+++ b/src/Monkey.php
@@ -13,10 +13,14 @@
 use Monkey\Parser\ProgramParser;
 use RuntimeException;
 use Symfony\Component\Console\Formatter\OutputFormatterStyle;
+use Symfony\Component\Console\Helper\QuestionHelper;
 use Symfony\Component\Console\Helper\Table;
 use Symfony\Component\Console\Helper\TableStyle;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\StringInput;
 use Symfony\Component\Console\Output\ConsoleOutput;
 use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Question\Question;
 use Throwable;
 
 use function count;
@@ -35,6 +39,10 @@ final class Monkey
 
     private readonly OutputInterface $output;
 
+    private readonly InputInterface $input;
+
+    private readonly QuestionHelper $questionHelper;
+
     private bool $debugMode = false;
 
     private bool $showStats = false;
@@ -50,10 +58,14 @@ public function __construct()
         $this->startMemory = memory_get_usage();
 
         $this->output = new ConsoleOutput();
+        $this->input = new StringInput('');
+        $this->questionHelper = new QuestionHelper();
+
         $this->output->getFormatter()->setStyle('title', new OutputFormatterStyle('white', null, ['bold']));
         $this->output->getFormatter()->setStyle('memory', new OutputFormatterStyle('green'));
         $this->output->getFormatter()->setStyle('peak', new OutputFormatterStyle('yellow'));
         $this->output->getFormatter()->setStyle('time', new OutputFormatterStyle('blue'));
+        $this->output->getFormatter()->setStyle('prompt', new OutputFormatterStyle('cyan'));
     }
 
     /**
@@ -175,10 +187,11 @@ private function startRepl(): int
         $this->showWelcomeBanner();
 
         while (true) {
+            $this->output->writeln(''); // Add newline before prompt
             $input = $this->readInput();
 
             if ($input === false) {
-                echo PHP_EOL . 'Goodbye!' . PHP_EOL;
+                $this->output->writeln(PHP_EOL . 'Goodbye!');
 
                 return 0;
             }
@@ -301,7 +314,15 @@ private function showWelcomeBanner(): void
 
     private function readInput(): string | false
     {
-        return readline("\n➜ ");
+        $question = new Question('<prompt>➜</prompt> ');
+
+        try {
+            $answer = $this->questionHelper->ask($this->input, $this->output, $question);
+
+            return $answer ?? false;
+        } catch (Throwable) {
+            return false;
+        }
     }
 
     private function showVersion(): int

From fe045f54c8920138288891428da92331a88e6e4f Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 11:50:59 -0300
Subject: [PATCH 03/22] Chore

---
 src/Monkey.php | 67 ++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 51 insertions(+), 16 deletions(-)

diff --git a/src/Monkey.php b/src/Monkey.php
index 9336d71..d845d9d 100644
--- a/src/Monkey.php
+++ b/src/Monkey.php
@@ -26,6 +26,8 @@
 use function count;
 
 use function in_array;
+use function is_scalar;
+
 use function sprintf;
 
 use const PHP_EOL;
@@ -47,15 +49,13 @@ final class Monkey
 
     private bool $showStats = false;
 
-    private readonly float $startTime;
+    private ?float $evalStartTime = null;
 
-    private readonly int $startMemory;
+    private ?int $evalStartMemory = null;
 
     public function __construct()
     {
         $this->environment = new Environment();
-        $this->startTime = microtime(true);
-        $this->startMemory = memory_get_usage();
 
         $this->output = new ConsoleOutput();
         $this->input = new StringInput('');
@@ -117,13 +117,29 @@ public function run(array $argv): int
         }
     }
 
+    private function startPerfTracking(): void
+    {
+        $this->evalStartTime = microtime(true);
+        $this->evalStartMemory = memory_get_usage();
+    }
+
+    private function stopPerfTracking(): void
+    {
+        $this->evalStartTime = null;
+        $this->evalStartMemory = null;
+    }
+
     private function printPerformanceStats(): void
     {
+        if ($this->evalStartTime === null || $this->evalStartMemory === null) {
+            return;
+        }
+
         $timeEnd = microtime(true);
         $memEnd = memory_get_usage();
-        $memUsed = $memEnd - $this->startMemory;
+        $memUsed = $memEnd - $this->evalStartMemory;
         $peakMem = memory_get_peak_usage(true);
-        $timeTaken = $timeEnd - $this->startTime;
+        $timeTaken = $timeEnd - $this->evalStartTime;
 
         $this->output->writeln('');
         $this->output->writeln('');
@@ -148,6 +164,8 @@ private function printPerformanceStats(): void
         $table->render();
 
         $this->output->writeln('');
+
+        $this->stopPerfTracking();
     }
 
     private function writeOutput(MonkeyObject $result): void
@@ -235,19 +253,32 @@ private function runFile(?string $filename): int
 
     private function evaluate(string $input): MonkeyObject
     {
-        $lexer = new Lexer($input);
-        $parser = new Parser($lexer);
+        try {
+            $this->startPerfTracking();
 
-        $errors = $parser->errors();
+            $lexer = new Lexer($input);
+            $parser = new Parser($lexer);
 
-        if ($errors !== []) {
-            throw new RuntimeException("Parser errors:\n" . implode("\n", $errors));
-        }
+            $errors = $parser->errors();
 
-        $program = new ProgramParser()($parser);
-        $evaluator = new Evaluator();
+            if ($errors !== []) {
+                throw new RuntimeException("Parser errors:\n" . implode("\n", $errors));
+            }
+
+            $program = new ProgramParser()($parser);
+            $evaluator = new Evaluator();
+            $result = $evaluator->eval($program, $this->environment);
+
+            if ($this->showStats) {
+                $this->printPerformanceStats();
+            }
 
-        return $evaluator->eval($program, $this->environment);
+            return $result;
+        } catch (Throwable $throwable) {
+            $this->stopPerfTracking();
+
+            throw $throwable;
+        }
     }
 
     private function handleSpecialCommand(string $input): bool
@@ -319,7 +350,11 @@ private function readInput(): string | false
         try {
             $answer = $this->questionHelper->ask($this->input, $this->output, $question);
 
-            return $answer ?? false;
+            if (!is_scalar($answer)) {
+                return false;
+            }
+
+            return (string)$answer;
         } catch (Throwable) {
             return false;
         }

From 131afc4b16db6a2ce85beed4d48207178ad95454 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 12:34:45 -0300
Subject: [PATCH 04/22] Chore

---
 monkey                                        |  43 +-
 src/Monkey.php                                | 390 ------------------
 src/Monkey/Command/Command.php                |  12 +
 src/Monkey/Command/CommandFactory.php         |  44 ++
 src/Monkey/Command/CommandRunner.php          |  22 +
 src/Monkey/Command/HelpCommand.php            |  37 ++
 src/Monkey/Command/ReplCommand.php            |  21 +
 src/Monkey/Command/RunFileCommand.php         |  82 ++++
 src/Monkey/Command/VersionCommand.php         |  23 ++
 src/Monkey/Config/Configuration.php           |  30 ++
 src/Monkey/Config/ConfigurationManager.php    |  57 +++
 .../Exceptions/MonkeyRuntimeException.php     |  22 +
 src/Monkey/IO/ConsoleOutput.php               |  11 +
 src/Monkey/IO/FileReader.php                  |  30 ++
 src/Monkey/IO/InputReader.php                 |  40 ++
 src/Monkey/IO/InputValidator.php              |  37 ++
 src/Monkey/IO/OutputFormatter.php             | 115 ++++++
 src/Monkey/Monkey.php                         |  40 ++
 src/Monkey/Performance/PerformanceMetrics.php |  15 +
 src/Monkey/Performance/PerformanceTracker.php |  38 ++
 src/Monkey/Repl/ReplManager.php               | 233 +++++++++++
 21 files changed, 949 insertions(+), 393 deletions(-)
 delete mode 100644 src/Monkey.php
 create mode 100644 src/Monkey/Command/Command.php
 create mode 100644 src/Monkey/Command/CommandFactory.php
 create mode 100644 src/Monkey/Command/CommandRunner.php
 create mode 100644 src/Monkey/Command/HelpCommand.php
 create mode 100644 src/Monkey/Command/ReplCommand.php
 create mode 100644 src/Monkey/Command/RunFileCommand.php
 create mode 100644 src/Monkey/Command/VersionCommand.php
 create mode 100644 src/Monkey/Config/Configuration.php
 create mode 100644 src/Monkey/Config/ConfigurationManager.php
 create mode 100644 src/Monkey/Exceptions/MonkeyRuntimeException.php
 create mode 100644 src/Monkey/IO/ConsoleOutput.php
 create mode 100644 src/Monkey/IO/FileReader.php
 create mode 100644 src/Monkey/IO/InputReader.php
 create mode 100644 src/Monkey/IO/InputValidator.php
 create mode 100644 src/Monkey/IO/OutputFormatter.php
 create mode 100644 src/Monkey/Monkey.php
 create mode 100644 src/Monkey/Performance/PerformanceMetrics.php
 create mode 100644 src/Monkey/Performance/PerformanceTracker.php
 create mode 100644 src/Monkey/Repl/ReplManager.php

diff --git a/monkey b/monkey
index eb78a6d..d8e704b 100755
--- a/monkey
+++ b/monkey
@@ -5,7 +5,17 @@ declare(strict_types=1);
 
 require 'vendor/autoload.php';
 
-use Monkey\Monkey;
+use Monkey\Monkey\Command\CommandFactory;
+use Monkey\Monkey\Command\CommandRunner;
+use Monkey\Monkey\Config\ConfigurationManager;
+use Monkey\Monkey\IO\ConsoleOutput;
+use Monkey\Monkey\IO\InputReader;
+use Monkey\Monkey\IO\OutputFormatter;
+use Monkey\Monkey\Monkey;
+use Monkey\Monkey\Performance\PerformanceTracker;
+use Monkey\Monkey\Repl\ReplManager;
+use Symfony\Component\Console\Helper\QuestionHelper;
+use Symfony\Component\Console\Input\ArgvInput;
 
 if (PHP_SAPI !== 'cli') {
     exit;
@@ -15,5 +25,32 @@ if (!isset($GLOBALS['argv']) || !is_array($GLOBALS['argv'])) {
     exit(1);
 }
 
-$cli = new Monkey();
-exit($cli->run($GLOBALS['argv']));
+try {
+    $input = new ArgvInput();
+    $output = new ConsoleOutput();
+    $questionHelper = new QuestionHelper();
+
+    $outputFormatter = new OutputFormatter($output);
+    $inputReader = new InputReader($input, $output, $questionHelper);
+    $performanceTracker = new PerformanceTracker();
+    $replManager = new ReplManager(
+        $inputReader,
+        $outputFormatter,
+        $performanceTracker
+    );
+
+    $commandFactory = new CommandFactory(
+        //$inputReader,
+        $outputFormatter,
+        $performanceTracker,
+        $replManager
+    );
+    $commandRunner = new CommandRunner($commandFactory);
+    $configManager = new ConfigurationManager();
+
+    $monkey = new Monkey($commandRunner, $configManager);
+    exit($monkey->run($GLOBALS['argv']));
+} catch (Throwable $e) {
+    fwrite(STDERR, "Fatal error: {$e->getMessage()}\n");
+    exit(1);
+}
diff --git a/src/Monkey.php b/src/Monkey.php
deleted file mode 100644
index d845d9d..0000000
--- a/src/Monkey.php
+++ /dev/null
@@ -1,390 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Monkey;
-
-use Monkey\Evaluator\Environment;
-use Monkey\Evaluator\Evaluator;
-use Monkey\Lexer\Lexer;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
-use Monkey\Parser\Parser;
-use Monkey\Parser\ProgramParser;
-use RuntimeException;
-use Symfony\Component\Console\Formatter\OutputFormatterStyle;
-use Symfony\Component\Console\Helper\QuestionHelper;
-use Symfony\Component\Console\Helper\Table;
-use Symfony\Component\Console\Helper\TableStyle;
-use Symfony\Component\Console\Input\InputInterface;
-use Symfony\Component\Console\Input\StringInput;
-use Symfony\Component\Console\Output\ConsoleOutput;
-use Symfony\Component\Console\Output\OutputInterface;
-use Symfony\Component\Console\Question\Question;
-use Throwable;
-
-use function count;
-
-use function in_array;
-use function is_scalar;
-
-use function sprintf;
-
-use const PHP_EOL;
-use const STR_PAD_RIGHT;
-
-final class Monkey
-{
-    private const string VERSION = '1.0.0';
-
-    private readonly Environment $environment;
-
-    private readonly OutputInterface $output;
-
-    private readonly InputInterface $input;
-
-    private readonly QuestionHelper $questionHelper;
-
-    private bool $debugMode = false;
-
-    private bool $showStats = false;
-
-    private ?float $evalStartTime = null;
-
-    private ?int $evalStartMemory = null;
-
-    public function __construct()
-    {
-        $this->environment = new Environment();
-
-        $this->output = new ConsoleOutput();
-        $this->input = new StringInput('');
-        $this->questionHelper = new QuestionHelper();
-
-        $this->output->getFormatter()->setStyle('title', new OutputFormatterStyle('white', null, ['bold']));
-        $this->output->getFormatter()->setStyle('memory', new OutputFormatterStyle('green'));
-        $this->output->getFormatter()->setStyle('peak', new OutputFormatterStyle('yellow'));
-        $this->output->getFormatter()->setStyle('time', new OutputFormatterStyle('blue'));
-        $this->output->getFormatter()->setStyle('prompt', new OutputFormatterStyle('cyan'));
-    }
-
-    /**
-     * @param array<string> $argv
-     */
-    public function run(array $argv): int
-    {
-        if (count($argv) <= 1) {
-            return $this->showHelp();
-        }
-
-        if (in_array('--debug', $argv)) {
-            $this->debugMode = true;
-            $argv = array_values(array_filter($argv, fn ($arg): bool => $arg !== '--debug'));
-        }
-
-        if (in_array('--stats', $argv)) {
-            $this->showStats = true;
-            $argv = array_values(array_filter($argv, fn ($arg): bool => $arg !== '--stats'));
-        }
-
-        try {
-            // If we removed --debug and no other args remain, show help
-            if (count($argv) <= 1) {
-                return $this->showHelp();
-            }
-
-            $result = match ($argv[1]) {
-                'repl' => $this->startRepl(),
-                'run' => $this->runFile($argv[2] ?? null),
-                '--version', '-v' => $this->showVersion(),
-                '--help', '-h' => $this->showHelp(),
-                default => $this->showHelp(),
-            };
-
-            if ($this->showStats) {
-                $this->printPerformanceStats();
-            }
-
-            return $result;
-        } catch (Throwable $throwable) {
-            $this->writeError($throwable->getMessage());
-
-            if ($this->showStats) {
-                $this->printPerformanceStats();
-            }
-
-            return 1;
-        }
-    }
-
-    private function startPerfTracking(): void
-    {
-        $this->evalStartTime = microtime(true);
-        $this->evalStartMemory = memory_get_usage();
-    }
-
-    private function stopPerfTracking(): void
-    {
-        $this->evalStartTime = null;
-        $this->evalStartMemory = null;
-    }
-
-    private function printPerformanceStats(): void
-    {
-        if ($this->evalStartTime === null || $this->evalStartMemory === null) {
-            return;
-        }
-
-        $timeEnd = microtime(true);
-        $memEnd = memory_get_usage();
-        $memUsed = $memEnd - $this->evalStartMemory;
-        $peakMem = memory_get_peak_usage(true);
-        $timeTaken = $timeEnd - $this->evalStartTime;
-
-        $this->output->writeln('');
-        $this->output->writeln('');
-        $this->output->writeln('<title>Performance Statistics</title>');
-
-        $tableStyle = new TableStyle();
-        $tableStyle
-            ->setHorizontalBorderChars('-')
-            ->setVerticalBorderChars('|')
-            ->setCrossingChars('+', '+', '+', '+', '+', '+', '+', '+', '+')
-            ->setPadType(STR_PAD_RIGHT);
-
-        $table = new Table($this->output);
-        $table->setStyle($tableStyle);
-
-        $table->setRows([
-            ['Memory used', "<memory>{$this->formatBytes($memUsed)}</memory>"],
-            ['Peak memory', "<peak>{$this->formatBytes($peakMem)}</peak>"],
-            ['Time taken', '<time>' . number_format($timeTaken, 6) . ' seconds</time>'],
-        ]);
-
-        $table->render();
-
-        $this->output->writeln('');
-
-        $this->stopPerfTracking();
-    }
-
-    private function writeOutput(MonkeyObject $result): void
-    {
-        // Skip output for NullObject unless in debug mode
-        if ($result instanceof NullObject && !$this->debugMode) {
-            return;
-        }
-
-        if ($this->debugMode) {
-            $class = $result::class;
-            $this->output->write("<comment>{$class}:</comment> ");
-        }
-
-        $this->output->writeln($result->inspect());
-    }
-
-    private function writeError(string $message): void
-    {
-        $this->output->writeln("<error>Error: {$message}</error>");
-    }
-
-    private function formatBytes(int $bytes): string
-    {
-        $units = ['B', 'KB', 'MB', 'GB'];
-        $bytes = max($bytes, 0);
-        $pow = floor(($bytes ? log($bytes) : 0) / log(1024));
-        $pow = min($pow, count($units) - 1);
-
-        $bytes /= (1 << (10 * $pow));
-
-        return sprintf('%.2f %s', $bytes, $units[$pow]);
-    }
-
-    private function startRepl(): int
-    {
-        $this->showWelcomeBanner();
-
-        while (true) {
-            $this->output->writeln(''); // Add newline before prompt
-            $input = $this->readInput();
-
-            if ($input === false) {
-                $this->output->writeln(PHP_EOL . 'Goodbye!');
-
-                return 0;
-            }
-
-            if (trim($input) === '') {
-                continue;
-            }
-
-            if ($this->handleSpecialCommand($input)) {
-                continue;
-            }
-
-            try {
-                $this->writeOutput($this->evaluate($input));
-            } catch (Throwable $e) {
-                $this->writeError($e->getMessage());
-            }
-        }
-    }
-
-    private function runFile(?string $filename): int
-    {
-        if ($filename === null) {
-            throw new RuntimeException('No input file specified');
-        }
-
-        if (!file_exists($filename)) {
-            throw new RuntimeException("File not found: {$filename}");
-        }
-
-        $contents = file_get_contents($filename);
-
-        if ($contents === false) {
-            throw new RuntimeException("Could not read file: {$filename}");
-        }
-
-        $this->writeOutput($this->evaluate($contents));
-
-        return 0;
-    }
-
-    private function evaluate(string $input): MonkeyObject
-    {
-        try {
-            $this->startPerfTracking();
-
-            $lexer = new Lexer($input);
-            $parser = new Parser($lexer);
-
-            $errors = $parser->errors();
-
-            if ($errors !== []) {
-                throw new RuntimeException("Parser errors:\n" . implode("\n", $errors));
-            }
-
-            $program = new ProgramParser()($parser);
-            $evaluator = new Evaluator();
-            $result = $evaluator->eval($program, $this->environment);
-
-            if ($this->showStats) {
-                $this->printPerformanceStats();
-            }
-
-            return $result;
-        } catch (Throwable $throwable) {
-            $this->stopPerfTracking();
-
-            throw $throwable;
-        }
-    }
-
-    private function handleSpecialCommand(string $input): bool
-    {
-        return match (trim($input)) {
-            ':q', ':quit', 'exit' => $this->handleQuit(),
-            ':h', ':help' => $this->handleHelp(),
-            ':c', ':clear' => $this->handleClear(),
-            ':d', ':debug' => $this->handleDebugToggle(),
-            default => false,
-        };
-    }
-
-    private function handleQuit(): bool
-    {
-        if ($this->showStats) {
-            $this->printPerformanceStats();
-        }
-
-        echo 'Goodbye!' . PHP_EOL;
-        exit(0);
-    }
-
-    private function handleHelp(): bool
-    {
-        echo <<<HELP
-        \nMonkey REPL Commands:
-        :q, :quit, exit   Exit the REPL
-        :h, :help         Show this help message
-        :c, :clear        Clear the screen
-        :d, :debug        Toggle debug mode
-
-        Press Ctrl+C to cancel current input
-        HELP . PHP_EOL;
-
-        return true;
-    }
-
-    private function handleClear(): bool
-    {
-        system('clear');
-        $this->showWelcomeBanner();
-
-        return true;
-    }
-
-    private function handleDebugToggle(): bool
-    {
-        $this->debugMode = !$this->debugMode;
-        echo 'Debug mode: ' . ($this->debugMode ? 'Enabled' : 'Disabled') . PHP_EOL;
-
-        return true;
-    }
-
-    private function showWelcomeBanner(): void
-    {
-        $version = self::VERSION;
-
-        echo <<<BANNER
-        🐒 Monkey Programming Language v{$version}
-        Type ':h' for help, ':c' for clear, ':q' to quit
-        BANNER . PHP_EOL . PHP_EOL;
-    }
-
-    private function readInput(): string | false
-    {
-        $question = new Question('<prompt>➜</prompt> ');
-
-        try {
-            $answer = $this->questionHelper->ask($this->input, $this->output, $question);
-
-            if (!is_scalar($answer)) {
-                return false;
-            }
-
-            return (string)$answer;
-        } catch (Throwable) {
-            return false;
-        }
-    }
-
-    private function showVersion(): int
-    {
-        echo 'Monkey Programming Language v' . self::VERSION . PHP_EOL;
-
-        return 0;
-    }
-
-    private function showHelp(): int
-    {
-        echo <<<HELP
-        Usage: monkey [command]
-
-        Commands:
-            repl              Start the interactive REPL
-            run <file>        Execute a Monkey source file
-            --version, -v     Show version information
-            --help, -h        Show this help message
-            --debug           Enable debug mode
-            --stats           Show performance statistics
-
-        Examples:
-            monkey repl
-            monkey run example.monkey
-        HELP . PHP_EOL;
-
-        return 0;
-    }
-}
diff --git a/src/Monkey/Command/Command.php b/src/Monkey/Command/Command.php
new file mode 100644
index 0000000..1d2b68a
--- /dev/null
+++ b/src/Monkey/Command/Command.php
@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Command;
+
+use Monkey\Monkey\Config\Configuration;
+
+interface Command
+{
+    public function execute(Configuration $config): int;
+}
diff --git a/src/Monkey/Command/CommandFactory.php b/src/Monkey/Command/CommandFactory.php
new file mode 100644
index 0000000..e5b630b
--- /dev/null
+++ b/src/Monkey/Command/CommandFactory.php
@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Command;
+
+use Monkey\Monkey\IO\OutputFormatter;
+use Monkey\Monkey\Performance\PerformanceTracker;
+use Monkey\Monkey\Repl\ReplManager;
+use RuntimeException;
+
+final class CommandFactory
+{
+    private array $commands = [];
+
+    public function __construct(
+        private readonly OutputFormatter $outputFormatter,
+        private readonly PerformanceTracker $performanceTracker,
+        private readonly ReplManager $replManager,
+    ) {
+        $this->registerCommands();
+    }
+
+    public function create(string $commandName): Command
+    {
+        if (!isset($this->commands[$commandName])) {
+            throw new RuntimeException("Unknown command: {$commandName}");
+        }
+
+        return $this->commands[$commandName];
+    }
+
+    private function registerCommands(): void
+    {
+        $this->commands = [
+            'repl' => new ReplCommand($this->replManager, $this->outputFormatter),
+            'run' => new RunFileCommand($this->outputFormatter, $this->performanceTracker),
+            '--help' => new HelpCommand($this->outputFormatter),
+            '-h' => new HelpCommand($this->outputFormatter),
+            '--version' => new VersionCommand($this->outputFormatter),
+            '-v' => new VersionCommand($this->outputFormatter),
+        ];
+    }
+}
diff --git a/src/Monkey/Command/CommandRunner.php b/src/Monkey/Command/CommandRunner.php
new file mode 100644
index 0000000..fc5e38e
--- /dev/null
+++ b/src/Monkey/Command/CommandRunner.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Command;
+
+use Monkey\Monkey\Config\Configuration;
+
+final readonly class CommandRunner
+{
+    public function __construct(
+        private CommandFactory $commandFactory,
+    ) {
+    }
+
+    public function execute(Configuration $config): int
+    {
+        $command = $this->commandFactory->create($config->command);
+
+        return $command->execute($config);
+    }
+}
diff --git a/src/Monkey/Command/HelpCommand.php b/src/Monkey/Command/HelpCommand.php
new file mode 100644
index 0000000..47d5e38
--- /dev/null
+++ b/src/Monkey/Command/HelpCommand.php
@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Command;
+
+use Monkey\Monkey\Config\Configuration;
+use Monkey\Monkey\IO\OutputFormatter;
+
+final readonly class HelpCommand implements Command
+{
+    public function __construct(
+        private OutputFormatter $outputFormatter,
+    ) {
+    }
+
+    public function execute(Configuration $config): int
+    {
+        $this->outputFormatter->write(<<<HELP
+        Usage: monkey [command]
+
+        Commands:
+            repl              Start the interactive REPL
+            run <file>        Execute a Monkey source file
+            --version, -v     Show version information
+            --help, -h        Show this help message
+            --debug           Enable debug mode
+            --stats          Show performance statistics
+
+        Examples:
+            monkey repl
+            monkey run example.monkey
+        HELP);
+
+        return 0;
+    }
+}
diff --git a/src/Monkey/Command/ReplCommand.php b/src/Monkey/Command/ReplCommand.php
new file mode 100644
index 0000000..7e86a80
--- /dev/null
+++ b/src/Monkey/Command/ReplCommand.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Command;
+
+use Monkey\Monkey\Config\Configuration;
+use Monkey\Monkey\Repl\ReplManager;
+
+final readonly class ReplCommand implements Command
+{
+    public function __construct(
+        private ReplManager $replManager,
+    ) {
+    }
+
+    public function execute(Configuration $config): int
+    {
+        return $this->replManager->start($config);
+    }
+}
diff --git a/src/Monkey/Command/RunFileCommand.php b/src/Monkey/Command/RunFileCommand.php
new file mode 100644
index 0000000..2cbda0c
--- /dev/null
+++ b/src/Monkey/Command/RunFileCommand.php
@@ -0,0 +1,82 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Command;
+
+use Monkey\Evaluator\Environment;
+use Monkey\Evaluator\Evaluator;
+use Monkey\Lexer\Lexer;
+use Monkey\Monkey\Config\Configuration;
+use Monkey\Monkey\IO\OutputFormatter;
+use Monkey\Monkey\Performance\PerformanceTracker;
+use Monkey\Object\MonkeyObject;
+use Monkey\Parser\Parser;
+use Monkey\Parser\ProgramParser;
+use RuntimeException;
+use Throwable;
+
+final readonly class RunFileCommand implements Command
+{
+    public function __construct(
+        private OutputFormatter $outputFormatter,
+        private PerformanceTracker $performanceTracker,
+    ) {
+    }
+
+    public function execute(Configuration $config): int
+    {
+        $filename = $config->getFilename();
+
+        if ($filename === null) {
+            throw new RuntimeException('No input file specified');
+        }
+
+        if (!file_exists($filename)) {
+            throw new RuntimeException("File not found: {$filename}");
+        }
+
+        $contents = file_get_contents($filename);
+
+        if ($contents === false) {
+            throw new RuntimeException("Could not read file: {$filename}");
+        }
+
+        if ($config->hasStats()) {
+            $this->performanceTracker->start();
+        }
+
+        try {
+            $result = $this->evaluateCode($contents);
+            $this->outputFormatter->writeOutput($result, $config->hasDebug());
+
+            if ($config->hasStats()) {
+                $metrics = $this->performanceTracker->stop();
+                $this->outputFormatter->writePerformanceStats($metrics);
+            }
+
+            return 0;
+        } catch (Throwable $throwable) {
+            $this->outputFormatter->writeError($throwable->getMessage());
+
+            return 1;
+        }
+    }
+
+    private function evaluateCode(string $contents): MonkeyObject
+    {
+        $lexer = new Lexer($contents);
+        $parser = new Parser($lexer);
+
+        if ($parser->errors() !== []) {
+            throw new RuntimeException(
+                "Parser errors:\n" . implode("\n", $parser->errors()),
+            );
+        }
+
+        $program = new ProgramParser()($parser);
+        $evaluator = new Evaluator();
+
+        return $evaluator->eval($program, new Environment());
+    }
+}
diff --git a/src/Monkey/Command/VersionCommand.php b/src/Monkey/Command/VersionCommand.php
new file mode 100644
index 0000000..da7d795
--- /dev/null
+++ b/src/Monkey/Command/VersionCommand.php
@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Command;
+
+use Monkey\Monkey\Config\Configuration;
+use Monkey\Monkey\IO\OutputFormatter;
+
+final readonly class VersionCommand implements Command
+{
+    public function __construct(
+        private OutputFormatter $outputFormatter,
+    ) {
+    }
+
+    public function execute(Configuration $config): int
+    {
+        $this->outputFormatter->write('Monkey Programming Language v 1.0');
+
+        return 0;
+    }
+}
diff --git a/src/Monkey/Config/Configuration.php b/src/Monkey/Config/Configuration.php
new file mode 100644
index 0000000..80deea7
--- /dev/null
+++ b/src/Monkey/Config/Configuration.php
@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Config;
+
+final readonly class Configuration
+{
+    public function __construct(
+        public string $command,
+        public array $options,
+        public array $arguments,
+    ) {
+    }
+
+    public function hasDebug(): bool
+    {
+        return isset($this->options['debug']);
+    }
+
+    public function hasStats(): bool
+    {
+        return isset($this->options['stats']);
+    }
+
+    public function getFilename(): ?string
+    {
+        return $this->arguments[0] ?? null;
+    }
+}
diff --git a/src/Monkey/Config/ConfigurationManager.php b/src/Monkey/Config/ConfigurationManager.php
new file mode 100644
index 0000000..e5c7e80
--- /dev/null
+++ b/src/Monkey/Config/ConfigurationManager.php
@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Config;
+
+use RuntimeException;
+
+use function count;
+use function in_array;
+
+final class ConfigurationManager
+{
+    private const array VALID_COMMANDS = ['repl', 'run', '--version', '-v', '--help', '-h'];
+
+    private const array VALID_OPTIONS = ['--debug', '--stats'];
+
+    public function parseArguments(array $argv): Configuration
+    {
+        if (count($argv) <= 1) {
+            throw new RuntimeException('No command specified');
+        }
+
+        $options = [];
+        $arguments = [];
+        $command = '';
+
+        foreach ($argv as $index => $arg) {
+            if ($index === 0) {
+                continue;
+            } // Skip script name
+
+            if (str_starts_with((string)$arg, '--')) {
+                if (!in_array($arg, self::VALID_OPTIONS)) {
+                    throw new RuntimeException("Invalid option: {$arg}");
+                }
+
+                $options[trim((string)$arg, '-')] = true;
+            } elseif ($command === '') {
+                if (!in_array($arg, self::VALID_COMMANDS)) {
+                    throw new RuntimeException("Invalid command: {$arg}");
+                }
+
+                $command = $arg;
+            } else {
+                $arguments[] = $arg;
+            }
+        }
+
+        // If no command was found after processing options
+        if ($command === '') {
+            $command = '--help';
+        }
+
+        return new Configuration($command, $options, $arguments);
+    }
+}
diff --git a/src/Monkey/Exceptions/MonkeyRuntimeException.php b/src/Monkey/Exceptions/MonkeyRuntimeException.php
new file mode 100644
index 0000000..e761f03
--- /dev/null
+++ b/src/Monkey/Exceptions/MonkeyRuntimeException.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Exceptions;
+
+use RuntimeException;
+
+use function sprintf;
+
+final class MonkeyRuntimeException extends RuntimeException
+{
+    public static function fileNotFound(string $filename): self
+    {
+        return new self(sprintf('File "%s" not found', $filename));
+    }
+
+    public static function fileNotReadable(string $filename): self
+    {
+        return new self(sprintf('File "%s" is not readable', $filename));
+    }
+}
diff --git a/src/Monkey/IO/ConsoleOutput.php b/src/Monkey/IO/ConsoleOutput.php
new file mode 100644
index 0000000..023c0a2
--- /dev/null
+++ b/src/Monkey/IO/ConsoleOutput.php
@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\IO;
+
+use Symfony\Component\Console\Output\ConsoleOutput as SymfonyConsoleOutput;
+
+final class ConsoleOutput extends SymfonyConsoleOutput
+{
+}
diff --git a/src/Monkey/IO/FileReader.php b/src/Monkey/IO/FileReader.php
new file mode 100644
index 0000000..840d17d
--- /dev/null
+++ b/src/Monkey/IO/FileReader.php
@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\IO;
+
+use Monkey\Monkey\Exceptions\MonkeyRuntimeException;
+
+final class FileReader
+{
+    public function read(string $filename): string
+    {
+        if (!file_exists($filename)) {
+            throw MonkeyRuntimeException::fileNotFound($filename);
+        }
+
+        $contents = file_get_contents($filename);
+
+        if ($contents === false) {
+            throw MonkeyRuntimeException::fileNotReadable($filename);
+        }
+
+        return $contents;
+    }
+
+    public function isReadable(string $filename): bool
+    {
+        return file_exists($filename) && is_readable($filename);
+    }
+}
diff --git a/src/Monkey/IO/InputReader.php b/src/Monkey/IO/InputReader.php
new file mode 100644
index 0000000..52a21c7
--- /dev/null
+++ b/src/Monkey/IO/InputReader.php
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\IO;
+
+use Symfony\Component\Console\Helper\QuestionHelper;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Question\Question;
+use Throwable;
+
+use function is_scalar;
+
+final readonly class InputReader
+{
+    public function __construct(
+        private InputInterface $input,
+        private OutputInterface $output,
+        private QuestionHelper $questionHelper,
+    ) {
+    }
+
+    public function readLine(string $prompt = '➜ '): string | false
+    {
+        $question = new Question("<prompt>{$prompt}</prompt> ");
+
+        try {
+            $answer = $this->questionHelper->ask($this->input, $this->output, $question);
+
+            if (!is_scalar($answer)) {
+                return false;
+            }
+
+            return (string)$answer;
+        } catch (Throwable) {
+            return false;
+        }
+    }
+}
diff --git a/src/Monkey/IO/InputValidator.php b/src/Monkey/IO/InputValidator.php
new file mode 100644
index 0000000..b3b492a
--- /dev/null
+++ b/src/Monkey/IO/InputValidator.php
@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\IO;
+
+use Monkey\Monkey\Exceptions\MonkeyRuntimeException;
+
+use function in_array;
+use function sprintf;
+use function strlen;
+
+final class InputValidator
+{
+    public function validateNotEmpty(string $input): void
+    {
+        if (trim($input) === '') {
+            throw new MonkeyRuntimeException('Input cannot be empty');
+        }
+    }
+
+    public function validateMaxLength(string $input, int $maxLength): void
+    {
+        if (strlen($input) > $maxLength) {
+            throw new MonkeyRuntimeException(
+                sprintf('Input exceeds maximum length of %d characters', $maxLength),
+            );
+        }
+    }
+
+    public function validatePattern(string $input, string $pattern): void
+    {
+        if (in_array(preg_match($pattern, $input), [0, false], true)) {
+            throw new MonkeyRuntimeException('Input format is invalid');
+        }
+    }
+}
diff --git a/src/Monkey/IO/OutputFormatter.php b/src/Monkey/IO/OutputFormatter.php
new file mode 100644
index 0000000..c95d8c2
--- /dev/null
+++ b/src/Monkey/IO/OutputFormatter.php
@@ -0,0 +1,115 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\IO;
+
+use Monkey\Monkey\Performance\PerformanceMetrics;
+use Monkey\Object\MonkeyObject;
+use Monkey\Object\NullObject;
+use Symfony\Component\Console\Formatter\OutputFormatterStyle;
+use Symfony\Component\Console\Helper\Table;
+use Symfony\Component\Console\Helper\TableStyle;
+use Symfony\Component\Console\Output\OutputInterface;
+
+use function count;
+use function sprintf;
+
+use const STR_PAD_RIGHT;
+
+final readonly class OutputFormatter
+{
+    public function __construct(
+        private OutputInterface $output,
+    ) {
+        $this->configureStyles();
+    }
+
+    public function writeOutput(MonkeyObject $result, bool $debug = false): void
+    {
+        // Skip output for NullObject unless in debug mode
+        if ($result instanceof NullObject && !$debug) {
+            return;
+        }
+
+        if ($debug) {
+            $class = $result::class;
+            $this->output->write("<comment>{$class}:</comment> ");
+        }
+
+        $this->output->writeln($result->inspect());
+    }
+
+    public function writeError(string $message): void
+    {
+        $this->output->writeln("<error>Error: {$message}</error>");
+    }
+
+    public function write(string $message): void
+    {
+        $this->output->writeln($message);
+    }
+
+    public function writePerformanceStats(PerformanceMetrics $metrics): void
+    {
+        $this->output->writeln('');
+        $this->output->writeln('');
+        $this->output->writeln('<title>Performance Statistics</title>');
+
+        $tableStyle = new TableStyle();
+        $tableStyle
+            ->setHorizontalBorderChars('-')
+            ->setVerticalBorderChars('|')
+            ->setCrossingChars('+', '+', '+', '+', '+', '+', '+', '+', '+')
+            ->setPadType(STR_PAD_RIGHT);
+
+        $table = new Table($this->output);
+        $table->setStyle($tableStyle);
+
+        $table->setRows([
+            ['Memory used', "<memory>{$this->formatBytes($metrics->memoryUsed)}</memory>"],
+            ['Peak memory', "<peak>{$this->formatBytes($metrics->peakMemory)}</peak>"],
+            ['Time taken', '<time>' . number_format($metrics->timeElapsed, 6) . ' seconds</time>'],
+        ]);
+
+        $table->render();
+
+        $this->output->writeln('');
+    }
+
+    private function configureStyles(): void
+    {
+        $this->output->getFormatter()->setStyle(
+            'title',
+            new OutputFormatterStyle('white', null, ['bold']),
+        );
+        $this->output->getFormatter()->setStyle(
+            'memory',
+            new OutputFormatterStyle('green'),
+        );
+        $this->output->getFormatter()->setStyle(
+            'peak',
+            new OutputFormatterStyle('yellow'),
+        );
+        $this->output->getFormatter()->setStyle(
+            'time',
+            new OutputFormatterStyle('blue'),
+        );
+        $this->output->getFormatter()->setStyle(
+            'prompt',
+            new OutputFormatterStyle('cyan'),
+        );
+    }
+
+    private function formatBytes(int $bytes): string
+    {
+        $units = ['B', 'KB', 'MB', 'GB'];
+        $bytes = max($bytes, 0);
+        $pow = floor(($bytes ? log($bytes) : 0) / log(1024));
+        $pow = min($pow, count($units) - 1);
+
+        $bytes /= (1 << (10 * $pow));
+
+        return sprintf('%.2f %s', $bytes, $units[$pow]);
+    }
+}
diff --git a/src/Monkey/Monkey.php b/src/Monkey/Monkey.php
new file mode 100644
index 0000000..a5e30e1
--- /dev/null
+++ b/src/Monkey/Monkey.php
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey;
+
+use Monkey\Monkey\Command\CommandRunner;
+use Monkey\Monkey\Config\ConfigurationManager;
+use Throwable;
+
+use const STDERR;
+
+final readonly class Monkey
+{
+    private const string VERSION = '1.0.0';
+
+    public function __construct(
+        private CommandRunner $commandRunner,
+        private ConfigurationManager $configManager,
+    ) {
+    }
+
+    public static function version(): string
+    {
+        return self::VERSION;
+    }
+
+    public function run(array $argv): int
+    {
+        try {
+            $config = $this->configManager->parseArguments($argv);
+
+            return $this->commandRunner->execute($config);
+        } catch (Throwable $throwable) {
+            fwrite(STDERR, "Error: {$throwable->getMessage()}\n");
+
+            return 1;
+        }
+    }
+}
diff --git a/src/Monkey/Performance/PerformanceMetrics.php b/src/Monkey/Performance/PerformanceMetrics.php
new file mode 100644
index 0000000..cc4d613
--- /dev/null
+++ b/src/Monkey/Performance/PerformanceMetrics.php
@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Performance;
+
+final readonly class PerformanceMetrics
+{
+    public function __construct(
+        public float $timeElapsed,
+        public int $memoryUsed,
+        public int $peakMemory,
+    ) {
+    }
+}
diff --git a/src/Monkey/Performance/PerformanceTracker.php b/src/Monkey/Performance/PerformanceTracker.php
new file mode 100644
index 0000000..3438f11
--- /dev/null
+++ b/src/Monkey/Performance/PerformanceTracker.php
@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Performance;
+
+use RuntimeException;
+
+final class PerformanceTracker
+{
+    private ?float $startTime = null;
+
+    private ?int $startMemory = null;
+
+    public function start(): void
+    {
+        $this->startTime = microtime(true);
+        $this->startMemory = memory_get_usage();
+    }
+
+    public function stop(): PerformanceMetrics
+    {
+        if ($this->startTime === null || $this->startMemory === null) {
+            throw new RuntimeException('Performance tracking not started');
+        }
+
+        $metrics = new PerformanceMetrics(
+            timeElapsed: microtime(true) - $this->startTime,
+            memoryUsed: memory_get_usage() - $this->startMemory,
+            peakMemory: memory_get_peak_usage(true),
+        );
+
+        $this->startTime = null;
+        $this->startMemory = null;
+
+        return $metrics;
+    }
+}
diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
new file mode 100644
index 0000000..2806cc8
--- /dev/null
+++ b/src/Monkey/Repl/ReplManager.php
@@ -0,0 +1,233 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Monkey\Monkey\Repl;
+
+use Monkey\Evaluator\Environment;
+use Monkey\Evaluator\Evaluator;
+use Monkey\Lexer\Lexer;
+use Monkey\Monkey\Config\Configuration;
+use Monkey\Monkey\Exceptions\MonkeyRuntimeException;
+use Monkey\Monkey\IO\InputReader;
+use Monkey\Monkey\IO\OutputFormatter;
+use Monkey\Monkey\Performance\PerformanceTracker;
+use Monkey\Object\MonkeyObject;
+use Monkey\Parser\Parser;
+use Monkey\Parser\ProgramParser;
+use Throwable;
+
+use const PHP_OS_FAMILY;
+
+final class ReplManager
+{
+    private const array SPECIAL_COMMANDS = [
+        ':q' => 'handleQuit',
+        ':quit' => 'handleQuit',
+        'exit' => 'handleQuit',
+        ':h' => 'handleHelp',
+        ':help' => 'handleHelp',
+        ':c' => 'handleClear',
+        ':clear' => 'handleClear',
+        ':d' => 'handleDebugToggle',
+        ':debug' => 'handleDebugToggle',
+        ':r' => 'handleResetEnvironment',
+        ':reset' => 'handleResetEnvironment',
+    ];
+
+    private bool $debugMode = false;
+
+    private bool $running = true;
+
+    public function __construct(
+        private readonly InputReader $inputReader,
+        private readonly OutputFormatter $outputFormatter,
+        private readonly PerformanceTracker $performanceTracker,
+        private Environment $environment = new Environment(),
+        private readonly Evaluator $evaluator = new Evaluator(),
+    ) {
+    }
+
+    public function start(Configuration $config): int
+    {
+        try {
+            $this->debugMode = $config->hasDebug();
+            $this->showWelcomeBanner();
+
+            while ($this->running) {
+                $this->outputFormatter->write(''); // Add newline before prompt
+                $input = $this->inputReader->readLine();
+
+                if ($input === false) {
+                    $this->outputFormatter->write("\nGoodbye!");
+
+                    return 0;
+                }
+
+                if (trim($input) === '') {
+                    continue;
+                }
+
+                if ($this->handleSpecialCommand($input)) {
+                    continue;
+                }
+
+                try {
+                    $this->evaluateAndOutput($input, $config);
+                } catch (MonkeyRuntimeException $e) {
+                    $this->outputFormatter->writeError($e->getMessage());
+                } catch (Throwable $e) {
+                    $this->outputFormatter->writeError("Unexpected error: {$e->getMessage()}");
+
+                    if ($this->debugMode) {
+                        $this->outputFormatter->write($e->getTraceAsString());
+                    }
+                }
+            }
+
+            return 0;
+        } catch (Throwable $throwable) {
+            $this->outputFormatter->writeError("Fatal error: {$throwable->getMessage()}");
+
+            if ($this->debugMode) {
+                $this->outputFormatter->write($throwable->getTraceAsString());
+            }
+
+            return 1;
+        }
+    }
+
+    public function isDebugMode(): bool
+    {
+        return $this->debugMode;
+    }
+
+    public function getEnvironment(): Environment
+    {
+        return $this->environment;
+    }
+
+    private function evaluateAndOutput(string $input, Configuration $config): void
+    {
+        if ($config->hasStats()) {
+            $this->performanceTracker->start();
+        }
+
+        $result = $this->evaluate($input);
+        $this->outputFormatter->writeOutput($result, $this->debugMode);
+
+        if ($config->hasStats()) {
+            $metrics = $this->performanceTracker->stop();
+            $this->outputFormatter->writePerformanceStats($metrics);
+        }
+    }
+
+    private function evaluate(string $input): MonkeyObject
+    {
+        $lexer = new Lexer($input);
+        $parser = new Parser($lexer);
+
+        $errors = $parser->errors();
+
+        if ($errors !== []) {
+            throw new MonkeyRuntimeException(
+                "Parser errors:\n" . implode("\n", $errors),
+            );
+        }
+
+        $program = (new ProgramParser())($parser);
+
+        return $this->evaluator->eval($program, $this->environment);
+    }
+
+    private function handleSpecialCommand(string $input): bool
+    {
+        $trimmedInput = trim($input);
+
+        if (isset(self::SPECIAL_COMMANDS[$trimmedInput])) {
+            $method = self::SPECIAL_COMMANDS[$trimmedInput];
+
+            return $this->{$method}();
+        }
+
+        return false;
+    }
+
+    private function handleQuit(): bool
+    {
+        $this->running = false;
+        $this->outputFormatter->write('Goodbye!');
+
+        return true;
+    }
+
+    private function handleHelp(): bool
+    {
+        $this->outputFormatter->write(<<<HELP
+        \nMonkey REPL Commands:
+        :q, :quit, exit   Exit the REPL
+        :h, :help         Show this help message
+        :c, :clear        Clear the screen
+        :d, :debug        Toggle debug mode
+        :r, :reset        Reset the environment
+
+        Press Ctrl+C to cancel current input
+        HELP);
+
+        return true;
+    }
+
+    private function handleClear(): bool
+    {
+        if (PHP_OS_FAMILY === 'Windows') {
+            system('cls');
+        } else {
+            system('clear');
+        }
+
+        $this->showWelcomeBanner();
+
+        return true;
+    }
+
+    private function handleDebugToggle(): bool
+    {
+        $this->debugMode = !$this->debugMode;
+        $this->outputFormatter->write(
+            'Debug mode: ' . ($this->debugMode ? 'Enabled' : 'Disabled'),
+        );
+
+        return true;
+    }
+
+    private function handleResetEnvironment(): bool
+    {
+        $this->environment = new Environment();
+        $this->outputFormatter->write('Environment has been reset');
+
+        return true;
+    }
+
+    private function showWelcomeBanner(): void
+    {
+        $this->outputFormatter->write(<<<BANNER
+                    __,__
+           .--.  .-"     "-.  .--.
+          / .. \\/  .-. .-.  \\/ .. \\
+         | |  '|  /   Y   \\  |'  | |
+         | \\   \\  \\ 0 | 0 /  /   / |
+          \\ '- ,\\.-"`` ``"-./, -' /
+           `'-' /_   ^ ^   _\\ '-'`
+               |  \\._   _./  |
+               \\   \\ `~` /   /
+                '._ '-=-' _.'
+                   '~---~'
+        -------------------------------
+        | Monkey Programming Language |
+        -------------------------------
+
+        Type ':h' for help, ':c' for clear, ':q' to quit
+        BANNER);
+        $this->outputFormatter->write('');
+    }
+}

From 5f80cd0de36d8899b7dd41d2c22646305f9df81a Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 12:36:23 -0300
Subject: [PATCH 05/22] Namespace

---
 composer.json                                 |  2 +-
 monkey                                        | 18 ++---
 src/Ast/Expressions/BinaryExpression.php      |  6 +-
 src/Ast/Expressions/CallExpression.php        |  6 +-
 src/Ast/Expressions/Expression.php            |  4 +-
 src/Ast/Expressions/IdentifierExpression.php  |  4 +-
 src/Ast/Expressions/IfExpression.php          |  8 +-
 src/Ast/Expressions/IndexExpression.php       |  6 +-
 src/Ast/Expressions/PostfixExpression.php     |  6 +-
 src/Ast/Expressions/UnaryExpression.php       |  6 +-
 src/Ast/Expressions/WhileExpression.php       |  8 +-
 src/Ast/Node.php                              |  2 +-
 src/Ast/Program.php                           |  6 +-
 src/Ast/Statements/AssignStatement.php        | 10 +--
 src/Ast/Statements/BlockStatement.php         |  8 +-
 src/Ast/Statements/ExpressionStatement.php    |  6 +-
 src/Ast/Statements/LetStatement.php           | 10 +--
 src/Ast/Statements/ReturnStatement.php        | 10 +--
 src/Ast/Statements/Statement.php              |  4 +-
 src/Ast/Types/ArrayLiteral.php                |  8 +-
 src/Ast/Types/BooleanLiteral.php              |  6 +-
 src/Ast/Types/FloatLiteral.php                |  6 +-
 src/Ast/Types/FunctionLiteral.php             | 12 +--
 src/Ast/Types/IntegerLiteral.php              |  6 +-
 src/Ast/Types/StringLiteral.php               |  6 +-
 src/Evaluator/Builtin/EvalBuiltinFunction.php |  6 +-
 src/Evaluator/Builtin/EvalFirstFunction.php   | 10 +--
 src/Evaluator/Builtin/EvalLastFunction.php    | 10 +--
 src/Evaluator/Builtin/EvalLenFunction.php     | 12 +--
 src/Evaluator/Builtin/EvalMapFunction.php     | 12 +--
 src/Evaluator/Builtin/EvalPushFunction.php    |  8 +-
 src/Evaluator/Builtin/EvalPutsFunction.php    |  8 +-
 src/Evaluator/Builtin/EvalSliceFunction.php   | 12 +--
 src/Evaluator/BuiltinFunction.php             |  6 +-
 src/Evaluator/Environment.php                 |  4 +-
 src/Evaluator/EvalArrayBinaryExpression.php   |  8 +-
 src/Evaluator/EvalArrayLiteral.php            | 10 +--
 src/Evaluator/EvalAssingStatement.php         |  8 +-
 src/Evaluator/EvalBinaryExpression.php        | 18 ++---
 src/Evaluator/EvalBlockStatement.php          | 12 +--
 src/Evaluator/EvalCallExpression.php          | 16 ++--
 src/Evaluator/EvalIdentifier.php              |  8 +-
 src/Evaluator/EvalIfExpression.php            | 12 +--
 src/Evaluator/EvalIndexExpression.php         | 16 ++--
 src/Evaluator/EvalLetStatement.php            |  8 +-
 .../EvalMinusUnaryOperatorExpression.php      |  8 +-
 src/Evaluator/EvalNotOperatorExpression.php   |  8 +-
 src/Evaluator/EvalNumericBinaryExpression.php |  8 +-
 src/Evaluator/EvalPostfixExpression.php       | 10 +--
 src/Evaluator/EvalProgram.php                 | 12 +--
 src/Evaluator/EvalReturnStatement.php         | 10 +--
 src/Evaluator/EvalStringBinaryExpression.php  | 10 +--
 src/Evaluator/EvalUnaryExpression.php         |  6 +-
 src/Evaluator/EvalWhileExpression.php         | 10 +--
 src/Evaluator/Evaluator.php                   | 76 +++++++++----------
 src/Lexer/Char.php                            |  2 +-
 src/Lexer/Input.php                           |  2 +-
 src/Lexer/Lexer.php                           |  6 +-
 src/Monkey/Command/Command.php                |  4 +-
 src/Monkey/Command/CommandFactory.php         |  8 +-
 src/Monkey/Command/CommandRunner.php          |  4 +-
 src/Monkey/Command/HelpCommand.php            |  6 +-
 src/Monkey/Command/ReplCommand.php            |  6 +-
 src/Monkey/Command/RunFileCommand.php         | 22 +++---
 src/Monkey/Command/VersionCommand.php         |  6 +-
 src/Monkey/Config/Configuration.php           |  2 +-
 src/Monkey/Config/ConfigurationManager.php    |  2 +-
 .../Exceptions/MonkeyRuntimeException.php     |  2 +-
 src/Monkey/IO/ConsoleOutput.php               |  2 +-
 src/Monkey/IO/FileReader.php                  |  4 +-
 src/Monkey/IO/InputReader.php                 |  2 +-
 src/Monkey/IO/InputValidator.php              |  4 +-
 src/Monkey/IO/OutputFormatter.php             |  8 +-
 src/Monkey/Monkey.php                         |  6 +-
 src/Monkey/Performance/PerformanceMetrics.php |  2 +-
 src/Monkey/Performance/PerformanceTracker.php |  2 +-
 src/Monkey/Repl/ReplManager.php               | 26 +++----
 src/Object/ArrayObject.php                    |  2 +-
 src/Object/BooleanObject.php                  |  2 +-
 src/Object/BuiltinFunctionObject.php          |  2 +-
 src/Object/ErrorObject.php                    |  2 +-
 src/Object/FloatObject.php                    |  2 +-
 src/Object/FunctionObject.php                 |  8 +-
 src/Object/IntegerObject.php                  |  2 +-
 src/Object/MonkeyObject.php                   |  2 +-
 src/Object/MonkeyObjectType.php               |  2 +-
 src/Object/NullObject.php                     |  2 +-
 src/Object/ReturnValueObject.php              |  2 +-
 src/Object/StringObject.php                   |  2 +-
 src/Parser/ExpressionListParser.php           |  6 +-
 src/Parser/FunctionParametersParser.php       |  6 +-
 src/Parser/Parselet/ArrayParselet.php         | 12 +--
 .../Parselet/BinaryOperatorParselet.php       |  8 +-
 .../Parselet/CallExpressionParselet.php       | 12 +--
 .../Parselet/FunctionLiteralParselet.php      | 16 ++--
 .../Parselet/GroupedExpressionParselet.php    | 10 +--
 src/Parser/Parselet/IdentifierParselet.php    |  8 +-
 src/Parser/Parselet/IfExpressionParselet.php  | 16 ++--
 .../Parselet/IndexExpressionParselet.php      | 12 +--
 src/Parser/Parselet/InfixParselet.php         |  4 +-
 .../Parselet/PostfixOperatorParselet.php      |  8 +-
 src/Parser/Parselet/PostfixParselet.php       |  4 +-
 src/Parser/Parselet/PrefixParselet.php        |  4 +-
 src/Parser/Parselet/ScalarParselet.php        | 16 ++--
 src/Parser/Parselet/UnaryOperatorParselet.php | 10 +--
 .../Parselet/WhileExpressionParselet.php      | 16 ++--
 src/Parser/Parser.php                         | 42 +++++-----
 src/Parser/Precedence.php                     |  2 +-
 src/Parser/ProgramParser.php                  | 10 +--
 .../Statements/AssignStatementParser.php      | 16 ++--
 .../Statements/BlockStatementParser.php       | 10 +--
 .../Statements/ExpressionStatementParser.php  | 12 +--
 src/Parser/Statements/LetStatementParser.php  | 16 ++--
 .../Statements/ReturnStatementParser.php      | 12 +--
 src/Parser/Statements/StatementParser.php     |  8 +-
 src/Support/StringBuilder.php                 |  2 +-
 src/Token/Token.php                           |  2 +-
 src/Token/TokenType.php                       |  6 +-
 tests/AstTest.php                             | 12 +--
 tests/EvaluatorTest.php                       | 20 ++---
 tests/Helpers.php                             | 20 ++---
 tests/LexerTest.php                           |  4 +-
 tests/ParserTest.php                          | 36 ++++-----
 123 files changed, 546 insertions(+), 546 deletions(-)

diff --git a/composer.json b/composer.json
index 8ebdd53..c5a0142 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,7 @@
   },
   "autoload": {
     "psr-4": {
-      "Monkey\\": "src"
+      "MonkeyLang\\": "src"
     }
   },
   "autoload-dev": {
diff --git a/monkey b/monkey
index d8e704b..11f4a97 100755
--- a/monkey
+++ b/monkey
@@ -5,15 +5,15 @@ declare(strict_types=1);
 
 require 'vendor/autoload.php';
 
-use Monkey\Monkey\Command\CommandFactory;
-use Monkey\Monkey\Command\CommandRunner;
-use Monkey\Monkey\Config\ConfigurationManager;
-use Monkey\Monkey\IO\ConsoleOutput;
-use Monkey\Monkey\IO\InputReader;
-use Monkey\Monkey\IO\OutputFormatter;
-use Monkey\Monkey\Monkey;
-use Monkey\Monkey\Performance\PerformanceTracker;
-use Monkey\Monkey\Repl\ReplManager;
+use MonkeyLang\Monkey\Command\CommandFactory;
+use MonkeyLang\Monkey\Command\CommandRunner;
+use MonkeyLang\Monkey\Config\ConfigurationManager;
+use MonkeyLang\Monkey\IO\ConsoleOutput;
+use MonkeyLang\Monkey\IO\InputReader;
+use MonkeyLang\Monkey\IO\OutputFormatter;
+use MonkeyLang\Monkey\Monkey;
+use MonkeyLang\Monkey\Performance\PerformanceTracker;
+use MonkeyLang\Monkey\Repl\ReplManager;
 use Symfony\Component\Console\Helper\QuestionHelper;
 use Symfony\Component\Console\Input\ArgvInput;
 
diff --git a/src/Ast/Expressions/BinaryExpression.php b/src/Ast/Expressions/BinaryExpression.php
index 606ada0..6ca0f8f 100644
--- a/src/Ast/Expressions/BinaryExpression.php
+++ b/src/Ast/Expressions/BinaryExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class BinaryExpression extends Expression
 {
diff --git a/src/Ast/Expressions/CallExpression.php b/src/Ast/Expressions/CallExpression.php
index bc7a42f..ad619fa 100644
--- a/src/Ast/Expressions/CallExpression.php
+++ b/src/Ast/Expressions/CallExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 use function count;
 
diff --git a/src/Ast/Expressions/Expression.php b/src/Ast/Expressions/Expression.php
index 0c95382..b95f7e7 100644
--- a/src/Ast/Expressions/Expression.php
+++ b/src/Ast/Expressions/Expression.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Ast\Node;
+use MonkeyLang\Ast\Node;
 
 abstract class Expression extends Node
 {
diff --git a/src/Ast/Expressions/IdentifierExpression.php b/src/Ast/Expressions/IdentifierExpression.php
index 1fde759..aba00c2 100644
--- a/src/Ast/Expressions/IdentifierExpression.php
+++ b/src/Ast/Expressions/IdentifierExpression.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Token\Token;
+use MonkeyLang\Token\Token;
 
 final class IdentifierExpression extends Expression
 {
diff --git a/src/Ast/Expressions/IfExpression.php b/src/Ast/Expressions/IfExpression.php
index 6cbee49..0619338 100644
--- a/src/Ast/Expressions/IfExpression.php
+++ b/src/Ast/Expressions/IfExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class IfExpression extends Expression
 {
diff --git a/src/Ast/Expressions/IndexExpression.php b/src/Ast/Expressions/IndexExpression.php
index 0103042..8ee8bdb 100644
--- a/src/Ast/Expressions/IndexExpression.php
+++ b/src/Ast/Expressions/IndexExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class IndexExpression extends Expression
 {
diff --git a/src/Ast/Expressions/PostfixExpression.php b/src/Ast/Expressions/PostfixExpression.php
index 1013baf..f06d938 100644
--- a/src/Ast/Expressions/PostfixExpression.php
+++ b/src/Ast/Expressions/PostfixExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class PostfixExpression extends Expression
 {
diff --git a/src/Ast/Expressions/UnaryExpression.php b/src/Ast/Expressions/UnaryExpression.php
index 160725c..0243e9f 100644
--- a/src/Ast/Expressions/UnaryExpression.php
+++ b/src/Ast/Expressions/UnaryExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class UnaryExpression extends Expression
 {
diff --git a/src/Ast/Expressions/WhileExpression.php b/src/Ast/Expressions/WhileExpression.php
index da01e47..dee2e7d 100644
--- a/src/Ast/Expressions/WhileExpression.php
+++ b/src/Ast/Expressions/WhileExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Expressions;
+namespace MonkeyLang\Ast\Expressions;
 
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class WhileExpression extends Expression
 {
diff --git a/src/Ast/Node.php b/src/Ast/Node.php
index 4034f65..a3290c5 100644
--- a/src/Ast/Node.php
+++ b/src/Ast/Node.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast;
+namespace MonkeyLang\Ast;
 
 use Stringable;
 
diff --git a/src/Ast/Program.php b/src/Ast/Program.php
index c189859..f8c0fad 100644
--- a/src/Ast/Program.php
+++ b/src/Ast/Program.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast;
+namespace MonkeyLang\Ast;
 
-use Monkey\Ast\Statements\Statement;
+use MonkeyLang\Ast\Statements\Statement;
 
-use Monkey\Support\StringBuilder;
+use MonkeyLang\Support\StringBuilder;
 
 use function count;
 
diff --git a/src/Ast/Statements/AssignStatement.php b/src/Ast/Statements/AssignStatement.php
index d98a1cf..6439b22 100644
--- a/src/Ast/Statements/AssignStatement.php
+++ b/src/Ast/Statements/AssignStatement.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class AssignStatement extends Statement
 {
diff --git a/src/Ast/Statements/BlockStatement.php b/src/Ast/Statements/BlockStatement.php
index 3638227..e50095f 100644
--- a/src/Ast/Statements/BlockStatement.php
+++ b/src/Ast/Statements/BlockStatement.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class BlockStatement extends Statement
 {
diff --git a/src/Ast/Statements/ExpressionStatement.php b/src/Ast/Statements/ExpressionStatement.php
index b2054a8..b893277 100644
--- a/src/Ast/Statements/ExpressionStatement.php
+++ b/src/Ast/Statements/ExpressionStatement.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Token\Token;
 
 final class ExpressionStatement extends Statement
 {
diff --git a/src/Ast/Statements/LetStatement.php b/src/Ast/Statements/LetStatement.php
index b385491..be5c5bf 100644
--- a/src/Ast/Statements/LetStatement.php
+++ b/src/Ast/Statements/LetStatement.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class LetStatement extends Statement
 {
diff --git a/src/Ast/Statements/ReturnStatement.php b/src/Ast/Statements/ReturnStatement.php
index be0eef8..a3c70e6 100644
--- a/src/Ast/Statements/ReturnStatement.php
+++ b/src/Ast/Statements/ReturnStatement.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 final class ReturnStatement extends Statement
 {
diff --git a/src/Ast/Statements/Statement.php b/src/Ast/Statements/Statement.php
index ef010f1..6d753d5 100644
--- a/src/Ast/Statements/Statement.php
+++ b/src/Ast/Statements/Statement.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Statements;
+namespace MonkeyLang\Ast\Statements;
 
-use Monkey\Ast\Node;
+use MonkeyLang\Ast\Node;
 
 abstract class Statement extends Node
 {
diff --git a/src/Ast/Types/ArrayLiteral.php b/src/Ast/Types/ArrayLiteral.php
index 7ad7f0d..93d4748 100644
--- a/src/Ast/Types/ArrayLiteral.php
+++ b/src/Ast/Types/ArrayLiteral.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Types;
+namespace MonkeyLang\Ast\Types;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 use function count;
 
diff --git a/src/Ast/Types/BooleanLiteral.php b/src/Ast/Types/BooleanLiteral.php
index e603226..9e2aed2 100644
--- a/src/Ast/Types/BooleanLiteral.php
+++ b/src/Ast/Types/BooleanLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Types;
+namespace MonkeyLang\Ast\Types;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Token\Token;
 
 final class BooleanLiteral extends Expression
 {
diff --git a/src/Ast/Types/FloatLiteral.php b/src/Ast/Types/FloatLiteral.php
index 8350a0a..31102ae 100644
--- a/src/Ast/Types/FloatLiteral.php
+++ b/src/Ast/Types/FloatLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Types;
+namespace MonkeyLang\Ast\Types;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Token\Token;
 
 final class FloatLiteral extends Expression
 {
diff --git a/src/Ast/Types/FunctionLiteral.php b/src/Ast/Types/FunctionLiteral.php
index 6e15721..184f1a6 100644
--- a/src/Ast/Types/FunctionLiteral.php
+++ b/src/Ast/Types/FunctionLiteral.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Types;
+namespace MonkeyLang\Ast\Types;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Support\StringBuilder;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Token\Token;
 
 use function count;
 
diff --git a/src/Ast/Types/IntegerLiteral.php b/src/Ast/Types/IntegerLiteral.php
index 3ee392c..ef4e84e 100644
--- a/src/Ast/Types/IntegerLiteral.php
+++ b/src/Ast/Types/IntegerLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Types;
+namespace MonkeyLang\Ast\Types;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Token\Token;
 
 final class IntegerLiteral extends Expression
 {
diff --git a/src/Ast/Types/StringLiteral.php b/src/Ast/Types/StringLiteral.php
index 12f1c6a..825c533 100644
--- a/src/Ast/Types/StringLiteral.php
+++ b/src/Ast/Types/StringLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Ast\Types;
+namespace MonkeyLang\Ast\Types;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Token\Token;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Token\Token;
 
 final class StringLiteral extends Expression
 {
diff --git a/src/Evaluator/Builtin/EvalBuiltinFunction.php b/src/Evaluator/Builtin/EvalBuiltinFunction.php
index ca364fb..ebfab33 100644
--- a/src/Evaluator/Builtin/EvalBuiltinFunction.php
+++ b/src/Evaluator/Builtin/EvalBuiltinFunction.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Evaluator\Evaluator;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Evaluator\Evaluator;
+use MonkeyLang\Object\MonkeyObject;
 
 abstract readonly class EvalBuiltinFunction
 {
diff --git a/src/Evaluator/Builtin/EvalFirstFunction.php b/src/Evaluator/Builtin/EvalFirstFunction.php
index 799766c..0359df3 100644
--- a/src/Evaluator/Builtin/EvalFirstFunction.php
+++ b/src/Evaluator/Builtin/EvalFirstFunction.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalLastFunction.php b/src/Evaluator/Builtin/EvalLastFunction.php
index d2663d9..208b1f5 100644
--- a/src/Evaluator/Builtin/EvalLastFunction.php
+++ b/src/Evaluator/Builtin/EvalLastFunction.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalLenFunction.php b/src/Evaluator/Builtin/EvalLenFunction.php
index fd7de98..b506833 100644
--- a/src/Evaluator/Builtin/EvalLenFunction.php
+++ b/src/Evaluator/Builtin/EvalLenFunction.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\StringObject;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\StringObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalMapFunction.php b/src/Evaluator/Builtin/EvalMapFunction.php
index 330afa8..24241e2 100644
--- a/src/Evaluator/Builtin/EvalMapFunction.php
+++ b/src/Evaluator/Builtin/EvalMapFunction.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\FunctionObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\FunctionObject;
+use MonkeyLang\Object\MonkeyObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalPushFunction.php b/src/Evaluator/Builtin/EvalPushFunction.php
index d63baa2..7d38c1a 100644
--- a/src/Evaluator/Builtin/EvalPushFunction.php
+++ b/src/Evaluator/Builtin/EvalPushFunction.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalPutsFunction.php b/src/Evaluator/Builtin/EvalPutsFunction.php
index becf514..b2580e0 100644
--- a/src/Evaluator/Builtin/EvalPutsFunction.php
+++ b/src/Evaluator/Builtin/EvalPutsFunction.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalSliceFunction.php b/src/Evaluator/Builtin/EvalSliceFunction.php
index 48c5a4d..58dac80 100644
--- a/src/Evaluator/Builtin/EvalSliceFunction.php
+++ b/src/Evaluator/Builtin/EvalSliceFunction.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator\Builtin;
+namespace MonkeyLang\Evaluator\Builtin;
 
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\StringObject;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\StringObject;
 
 use function array_slice;
 use function count;
diff --git a/src/Evaluator/BuiltinFunction.php b/src/Evaluator/BuiltinFunction.php
index 00e0d6a..40abace 100644
--- a/src/Evaluator/BuiltinFunction.php
+++ b/src/Evaluator/BuiltinFunction.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
 use Closure;
-use Monkey\Object\BuiltinFunctionObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Object\BuiltinFunctionObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final class BuiltinFunction
 {
diff --git a/src/Evaluator/Environment.php b/src/Evaluator/Environment.php
index 4a03aa7..8397798 100644
--- a/src/Evaluator/Environment.php
+++ b/src/Evaluator/Environment.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final class Environment
 {
diff --git a/src/Evaluator/EvalArrayBinaryExpression.php b/src/Evaluator/EvalArrayBinaryExpression.php
index 68bf03e..9e092ba 100644
--- a/src/Evaluator/EvalArrayBinaryExpression.php
+++ b/src/Evaluator/EvalArrayBinaryExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final class EvalArrayBinaryExpression
 {
diff --git a/src/Evaluator/EvalArrayLiteral.php b/src/Evaluator/EvalArrayLiteral.php
index 0372f39..da1db64 100644
--- a/src/Evaluator/EvalArrayLiteral.php
+++ b/src/Evaluator/EvalArrayLiteral.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Types\ArrayLiteral;
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 use function count;
 
diff --git a/src/Evaluator/EvalAssingStatement.php b/src/Evaluator/EvalAssingStatement.php
index 4b289b5..9677758 100644
--- a/src/Evaluator/EvalAssingStatement.php
+++ b/src/Evaluator/EvalAssingStatement.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Statements\AssignStatement;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Ast\Statements\AssignStatement;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final readonly class EvalAssingStatement
 {
diff --git a/src/Evaluator/EvalBinaryExpression.php b/src/Evaluator/EvalBinaryExpression.php
index 1dd3b01..29a251c 100644
--- a/src/Evaluator/EvalBinaryExpression.php
+++ b/src/Evaluator/EvalBinaryExpression.php
@@ -2,15 +2,15 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
-
-use Monkey\Object\ArrayObject;
-use Monkey\Object\BooleanObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\FloatObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\StringObject;
+namespace MonkeyLang\Evaluator;
+
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\BooleanObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\FloatObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\StringObject;
 
 final class EvalBinaryExpression
 {
diff --git a/src/Evaluator/EvalBlockStatement.php b/src/Evaluator/EvalBlockStatement.php
index 726a1ab..2bc4b0d 100644
--- a/src/Evaluator/EvalBlockStatement.php
+++ b/src/Evaluator/EvalBlockStatement.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
-use Monkey\Object\ReturnValueObject;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
+use MonkeyLang\Object\ReturnValueObject;
 
 final readonly class EvalBlockStatement
 {
diff --git a/src/Evaluator/EvalCallExpression.php b/src/Evaluator/EvalCallExpression.php
index 4632f10..53e5f8c 100644
--- a/src/Evaluator/EvalCallExpression.php
+++ b/src/Evaluator/EvalCallExpression.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
-
-use Monkey\Ast\Expressions\CallExpression;
-use Monkey\Object\BuiltinFunctionObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\FunctionObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\ReturnValueObject;
+namespace MonkeyLang\Evaluator;
+
+use MonkeyLang\Ast\Expressions\CallExpression;
+use MonkeyLang\Object\BuiltinFunctionObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\FunctionObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\ReturnValueObject;
 
 use function call_user_func;
 use function count;
diff --git a/src/Evaluator/EvalIdentifier.php b/src/Evaluator/EvalIdentifier.php
index 90fda02..080d4b0 100644
--- a/src/Evaluator/EvalIdentifier.php
+++ b/src/Evaluator/EvalIdentifier.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final readonly class EvalIdentifier
 {
diff --git a/src/Evaluator/EvalIfExpression.php b/src/Evaluator/EvalIfExpression.php
index 67f1429..370ddb2 100644
--- a/src/Evaluator/EvalIfExpression.php
+++ b/src/Evaluator/EvalIfExpression.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Expressions\IfExpression;
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
+use MonkeyLang\Ast\Expressions\IfExpression;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
 
 final readonly class EvalIfExpression
 {
diff --git a/src/Evaluator/EvalIndexExpression.php b/src/Evaluator/EvalIndexExpression.php
index bbe3269..402236a 100644
--- a/src/Evaluator/EvalIndexExpression.php
+++ b/src/Evaluator/EvalIndexExpression.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
-
-use Monkey\Ast\Expressions\IndexExpression;
-use Monkey\Object\ArrayObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
+namespace MonkeyLang\Evaluator;
+
+use MonkeyLang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
 
 final readonly class EvalIndexExpression
 {
diff --git a/src/Evaluator/EvalLetStatement.php b/src/Evaluator/EvalLetStatement.php
index 74f8365..7437fec 100644
--- a/src/Evaluator/EvalLetStatement.php
+++ b/src/Evaluator/EvalLetStatement.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Statements\LetStatement;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Ast\Statements\LetStatement;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final readonly class EvalLetStatement
 {
diff --git a/src/Evaluator/EvalMinusUnaryOperatorExpression.php b/src/Evaluator/EvalMinusUnaryOperatorExpression.php
index b81cbac..2abb607 100644
--- a/src/Evaluator/EvalMinusUnaryOperatorExpression.php
+++ b/src/Evaluator/EvalMinusUnaryOperatorExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Object\ErrorObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final class EvalMinusUnaryOperatorExpression
 {
diff --git a/src/Evaluator/EvalNotOperatorExpression.php b/src/Evaluator/EvalNotOperatorExpression.php
index 3f11695..46743b8 100644
--- a/src/Evaluator/EvalNotOperatorExpression.php
+++ b/src/Evaluator/EvalNotOperatorExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Object\BooleanObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
+use MonkeyLang\Object\BooleanObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
 
 final class EvalNotOperatorExpression
 {
diff --git a/src/Evaluator/EvalNumericBinaryExpression.php b/src/Evaluator/EvalNumericBinaryExpression.php
index e04d366..5b53000 100644
--- a/src/Evaluator/EvalNumericBinaryExpression.php
+++ b/src/Evaluator/EvalNumericBinaryExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Object\BooleanObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Object\BooleanObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final class EvalNumericBinaryExpression
 {
diff --git a/src/Evaluator/EvalPostfixExpression.php b/src/Evaluator/EvalPostfixExpression.php
index 4cebe18..f022174 100644
--- a/src/Evaluator/EvalPostfixExpression.php
+++ b/src/Evaluator/EvalPostfixExpression.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Expressions\PostfixExpression;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final readonly class EvalPostfixExpression
 {
diff --git a/src/Evaluator/EvalProgram.php b/src/Evaluator/EvalProgram.php
index 253e8a7..b1d4854 100644
--- a/src/Evaluator/EvalProgram.php
+++ b/src/Evaluator/EvalProgram.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Program;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
-use Monkey\Object\ReturnValueObject;
+use MonkeyLang\Ast\Program;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
+use MonkeyLang\Object\ReturnValueObject;
 
 final readonly class EvalProgram
 {
diff --git a/src/Evaluator/EvalReturnStatement.php b/src/Evaluator/EvalReturnStatement.php
index 5d6a4c2..75fd6f3 100644
--- a/src/Evaluator/EvalReturnStatement.php
+++ b/src/Evaluator/EvalReturnStatement.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Statements\ReturnStatement;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\ReturnValueObject;
+use MonkeyLang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\ReturnValueObject;
 
 final readonly class EvalReturnStatement
 {
diff --git a/src/Evaluator/EvalStringBinaryExpression.php b/src/Evaluator/EvalStringBinaryExpression.php
index c8610c2..a667893 100644
--- a/src/Evaluator/EvalStringBinaryExpression.php
+++ b/src/Evaluator/EvalStringBinaryExpression.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Object\BooleanObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\StringObject;
+use MonkeyLang\Object\BooleanObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\StringObject;
 
 final class EvalStringBinaryExpression
 {
diff --git a/src/Evaluator/EvalUnaryExpression.php b/src/Evaluator/EvalUnaryExpression.php
index 26bb673..5a01ce9 100644
--- a/src/Evaluator/EvalUnaryExpression.php
+++ b/src/Evaluator/EvalUnaryExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final class EvalUnaryExpression
 {
diff --git a/src/Evaluator/EvalWhileExpression.php b/src/Evaluator/EvalWhileExpression.php
index 264a860..0042895 100644
--- a/src/Evaluator/EvalWhileExpression.php
+++ b/src/Evaluator/EvalWhileExpression.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Expressions\WhileExpression;
-use Monkey\Object\BooleanObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\MonkeyObject;
+use MonkeyLang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Object\BooleanObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\MonkeyObject;
 
 final readonly class EvalWhileExpression
 {
diff --git a/src/Evaluator/Evaluator.php b/src/Evaluator/Evaluator.php
index 161e580..0f72e55 100644
--- a/src/Evaluator/Evaluator.php
+++ b/src/Evaluator/Evaluator.php
@@ -2,45 +2,45 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Evaluator;
+namespace MonkeyLang\Evaluator;
 
-use Monkey\Ast\Expressions\BinaryExpression;
-use Monkey\Ast\Expressions\CallExpression;
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Ast\Expressions\IfExpression;
-use Monkey\Ast\Expressions\IndexExpression;
-use Monkey\Ast\Expressions\PostfixExpression;
-use Monkey\Ast\Expressions\UnaryExpression;
-use Monkey\Ast\Expressions\WhileExpression;
-use Monkey\Ast\Node;
-use Monkey\Ast\Program;
-use Monkey\Ast\Statements\AssignStatement;
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Ast\Statements\ExpressionStatement;
-use Monkey\Ast\Statements\LetStatement;
-use Monkey\Ast\Statements\ReturnStatement;
-use Monkey\Ast\Types\ArrayLiteral;
-use Monkey\Ast\Types\BooleanLiteral;
-use Monkey\Ast\Types\FloatLiteral;
-use Monkey\Ast\Types\FunctionLiteral;
-use Monkey\Ast\Types\IntegerLiteral;
-use Monkey\Ast\Types\StringLiteral;
-use Monkey\Evaluator\Builtin\EvalFirstFunction;
-use Monkey\Evaluator\Builtin\EvalLastFunction;
-use Monkey\Evaluator\Builtin\EvalLenFunction;
-use Monkey\Evaluator\Builtin\EvalMapFunction;
-use Monkey\Evaluator\Builtin\EvalPushFunction;
-use Monkey\Evaluator\Builtin\EvalPutsFunction;
-use Monkey\Evaluator\Builtin\EvalSliceFunction;
-use Monkey\Object\BooleanObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\FloatObject;
-use Monkey\Object\FunctionObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
-use Monkey\Object\StringObject;
+use MonkeyLang\Ast\Expressions\BinaryExpression;
+use MonkeyLang\Ast\Expressions\CallExpression;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Ast\Expressions\IfExpression;
+use MonkeyLang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Ast\Expressions\UnaryExpression;
+use MonkeyLang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Ast\Node;
+use MonkeyLang\Ast\Program;
+use MonkeyLang\Ast\Statements\AssignStatement;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Ast\Statements\ExpressionStatement;
+use MonkeyLang\Ast\Statements\LetStatement;
+use MonkeyLang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Ast\Types\FloatLiteral;
+use MonkeyLang\Ast\Types\FunctionLiteral;
+use MonkeyLang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Ast\Types\StringLiteral;
+use MonkeyLang\Evaluator\Builtin\EvalFirstFunction;
+use MonkeyLang\Evaluator\Builtin\EvalLastFunction;
+use MonkeyLang\Evaluator\Builtin\EvalLenFunction;
+use MonkeyLang\Evaluator\Builtin\EvalMapFunction;
+use MonkeyLang\Evaluator\Builtin\EvalPushFunction;
+use MonkeyLang\Evaluator\Builtin\EvalPutsFunction;
+use MonkeyLang\Evaluator\Builtin\EvalSliceFunction;
+use MonkeyLang\Object\BooleanObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\FloatObject;
+use MonkeyLang\Object\FunctionObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
+use MonkeyLang\Object\StringObject;
 
 use function call_user_func;
 
diff --git a/src/Lexer/Char.php b/src/Lexer/Char.php
index 33c480c..3022b87 100644
--- a/src/Lexer/Char.php
+++ b/src/Lexer/Char.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Lexer;
+namespace MonkeyLang\Lexer;
 
 use Stringable;
 
diff --git a/src/Lexer/Input.php b/src/Lexer/Input.php
index 02795b8..a9a6d37 100644
--- a/src/Lexer/Input.php
+++ b/src/Lexer/Input.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Lexer;
+namespace MonkeyLang\Lexer;
 
 final class Input
 {
diff --git a/src/Lexer/Lexer.php b/src/Lexer/Lexer.php
index d4616c3..57ba799 100644
--- a/src/Lexer/Lexer.php
+++ b/src/Lexer/Lexer.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Lexer;
+namespace MonkeyLang\Lexer;
 
-use Monkey\Token\Token;
-use Monkey\Token\TokenType;
+use MonkeyLang\Token\Token;
+use MonkeyLang\Token\TokenType;
 
 final class Lexer
 {
diff --git a/src/Monkey/Command/Command.php b/src/Monkey/Command/Command.php
index 1d2b68a..5b8ab39 100644
--- a/src/Monkey/Command/Command.php
+++ b/src/Monkey/Command/Command.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Command;
+namespace MonkeyLang\Monkey\Command;
 
-use Monkey\Monkey\Config\Configuration;
+use MonkeyLang\Monkey\Config\Configuration;
 
 interface Command
 {
diff --git a/src/Monkey/Command/CommandFactory.php b/src/Monkey/Command/CommandFactory.php
index e5b630b..fa72b52 100644
--- a/src/Monkey/Command/CommandFactory.php
+++ b/src/Monkey/Command/CommandFactory.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Command;
+namespace MonkeyLang\Monkey\Command;
 
-use Monkey\Monkey\IO\OutputFormatter;
-use Monkey\Monkey\Performance\PerformanceTracker;
-use Monkey\Monkey\Repl\ReplManager;
+use MonkeyLang\Monkey\IO\OutputFormatter;
+use MonkeyLang\Monkey\Performance\PerformanceTracker;
+use MonkeyLang\Monkey\Repl\ReplManager;
 use RuntimeException;
 
 final class CommandFactory
diff --git a/src/Monkey/Command/CommandRunner.php b/src/Monkey/Command/CommandRunner.php
index fc5e38e..509f590 100644
--- a/src/Monkey/Command/CommandRunner.php
+++ b/src/Monkey/Command/CommandRunner.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Command;
+namespace MonkeyLang\Monkey\Command;
 
-use Monkey\Monkey\Config\Configuration;
+use MonkeyLang\Monkey\Config\Configuration;
 
 final readonly class CommandRunner
 {
diff --git a/src/Monkey/Command/HelpCommand.php b/src/Monkey/Command/HelpCommand.php
index 47d5e38..aa34caf 100644
--- a/src/Monkey/Command/HelpCommand.php
+++ b/src/Monkey/Command/HelpCommand.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Command;
+namespace MonkeyLang\Monkey\Command;
 
-use Monkey\Monkey\Config\Configuration;
-use Monkey\Monkey\IO\OutputFormatter;
+use MonkeyLang\Monkey\Config\Configuration;
+use MonkeyLang\Monkey\IO\OutputFormatter;
 
 final readonly class HelpCommand implements Command
 {
diff --git a/src/Monkey/Command/ReplCommand.php b/src/Monkey/Command/ReplCommand.php
index 7e86a80..4cc2a98 100644
--- a/src/Monkey/Command/ReplCommand.php
+++ b/src/Monkey/Command/ReplCommand.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Command;
+namespace MonkeyLang\Monkey\Command;
 
-use Monkey\Monkey\Config\Configuration;
-use Monkey\Monkey\Repl\ReplManager;
+use MonkeyLang\Monkey\Config\Configuration;
+use MonkeyLang\Monkey\Repl\ReplManager;
 
 final readonly class ReplCommand implements Command
 {
diff --git a/src/Monkey/Command/RunFileCommand.php b/src/Monkey/Command/RunFileCommand.php
index 2cbda0c..dc68017 100644
--- a/src/Monkey/Command/RunFileCommand.php
+++ b/src/Monkey/Command/RunFileCommand.php
@@ -2,17 +2,17 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Command;
-
-use Monkey\Evaluator\Environment;
-use Monkey\Evaluator\Evaluator;
-use Monkey\Lexer\Lexer;
-use Monkey\Monkey\Config\Configuration;
-use Monkey\Monkey\IO\OutputFormatter;
-use Monkey\Monkey\Performance\PerformanceTracker;
-use Monkey\Object\MonkeyObject;
-use Monkey\Parser\Parser;
-use Monkey\Parser\ProgramParser;
+namespace MonkeyLang\Monkey\Command;
+
+use MonkeyLang\Evaluator\Environment;
+use MonkeyLang\Evaluator\Evaluator;
+use MonkeyLang\Lexer\Lexer;
+use MonkeyLang\Monkey\Config\Configuration;
+use MonkeyLang\Monkey\IO\OutputFormatter;
+use MonkeyLang\Monkey\Performance\PerformanceTracker;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\ProgramParser;
 use RuntimeException;
 use Throwable;
 
diff --git a/src/Monkey/Command/VersionCommand.php b/src/Monkey/Command/VersionCommand.php
index da7d795..ba06153 100644
--- a/src/Monkey/Command/VersionCommand.php
+++ b/src/Monkey/Command/VersionCommand.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Command;
+namespace MonkeyLang\Monkey\Command;
 
-use Monkey\Monkey\Config\Configuration;
-use Monkey\Monkey\IO\OutputFormatter;
+use MonkeyLang\Monkey\Config\Configuration;
+use MonkeyLang\Monkey\IO\OutputFormatter;
 
 final readonly class VersionCommand implements Command
 {
diff --git a/src/Monkey/Config/Configuration.php b/src/Monkey/Config/Configuration.php
index 80deea7..56eabe7 100644
--- a/src/Monkey/Config/Configuration.php
+++ b/src/Monkey/Config/Configuration.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Config;
+namespace MonkeyLang\Monkey\Config;
 
 final readonly class Configuration
 {
diff --git a/src/Monkey/Config/ConfigurationManager.php b/src/Monkey/Config/ConfigurationManager.php
index e5c7e80..5f1d835 100644
--- a/src/Monkey/Config/ConfigurationManager.php
+++ b/src/Monkey/Config/ConfigurationManager.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Config;
+namespace MonkeyLang\Monkey\Config;
 
 use RuntimeException;
 
diff --git a/src/Monkey/Exceptions/MonkeyRuntimeException.php b/src/Monkey/Exceptions/MonkeyRuntimeException.php
index e761f03..c579522 100644
--- a/src/Monkey/Exceptions/MonkeyRuntimeException.php
+++ b/src/Monkey/Exceptions/MonkeyRuntimeException.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Exceptions;
+namespace MonkeyLang\Monkey\Exceptions;
 
 use RuntimeException;
 
diff --git a/src/Monkey/IO/ConsoleOutput.php b/src/Monkey/IO/ConsoleOutput.php
index 023c0a2..882f1d7 100644
--- a/src/Monkey/IO/ConsoleOutput.php
+++ b/src/Monkey/IO/ConsoleOutput.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\IO;
+namespace MonkeyLang\Monkey\IO;
 
 use Symfony\Component\Console\Output\ConsoleOutput as SymfonyConsoleOutput;
 
diff --git a/src/Monkey/IO/FileReader.php b/src/Monkey/IO/FileReader.php
index 840d17d..baee9dc 100644
--- a/src/Monkey/IO/FileReader.php
+++ b/src/Monkey/IO/FileReader.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\IO;
+namespace MonkeyLang\Monkey\IO;
 
-use Monkey\Monkey\Exceptions\MonkeyRuntimeException;
+use MonkeyLang\Monkey\Exceptions\MonkeyRuntimeException;
 
 final class FileReader
 {
diff --git a/src/Monkey/IO/InputReader.php b/src/Monkey/IO/InputReader.php
index 52a21c7..ff3452b 100644
--- a/src/Monkey/IO/InputReader.php
+++ b/src/Monkey/IO/InputReader.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\IO;
+namespace MonkeyLang\Monkey\IO;
 
 use Symfony\Component\Console\Helper\QuestionHelper;
 use Symfony\Component\Console\Input\InputInterface;
diff --git a/src/Monkey/IO/InputValidator.php b/src/Monkey/IO/InputValidator.php
index b3b492a..e9b5c46 100644
--- a/src/Monkey/IO/InputValidator.php
+++ b/src/Monkey/IO/InputValidator.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\IO;
+namespace MonkeyLang\Monkey\IO;
 
-use Monkey\Monkey\Exceptions\MonkeyRuntimeException;
+use MonkeyLang\Monkey\Exceptions\MonkeyRuntimeException;
 
 use function in_array;
 use function sprintf;
diff --git a/src/Monkey/IO/OutputFormatter.php b/src/Monkey/IO/OutputFormatter.php
index c95d8c2..9c59006 100644
--- a/src/Monkey/IO/OutputFormatter.php
+++ b/src/Monkey/IO/OutputFormatter.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\IO;
+namespace MonkeyLang\Monkey\IO;
 
-use Monkey\Monkey\Performance\PerformanceMetrics;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\NullObject;
+use MonkeyLang\Monkey\Performance\PerformanceMetrics;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\NullObject;
 use Symfony\Component\Console\Formatter\OutputFormatterStyle;
 use Symfony\Component\Console\Helper\Table;
 use Symfony\Component\Console\Helper\TableStyle;
diff --git a/src/Monkey/Monkey.php b/src/Monkey/Monkey.php
index a5e30e1..a123547 100644
--- a/src/Monkey/Monkey.php
+++ b/src/Monkey/Monkey.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey;
+namespace MonkeyLang\Monkey;
 
-use Monkey\Monkey\Command\CommandRunner;
-use Monkey\Monkey\Config\ConfigurationManager;
+use MonkeyLang\Monkey\Command\CommandRunner;
+use MonkeyLang\Monkey\Config\ConfigurationManager;
 use Throwable;
 
 use const STDERR;
diff --git a/src/Monkey/Performance/PerformanceMetrics.php b/src/Monkey/Performance/PerformanceMetrics.php
index cc4d613..295f8ec 100644
--- a/src/Monkey/Performance/PerformanceMetrics.php
+++ b/src/Monkey/Performance/PerformanceMetrics.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Performance;
+namespace MonkeyLang\Monkey\Performance;
 
 final readonly class PerformanceMetrics
 {
diff --git a/src/Monkey/Performance/PerformanceTracker.php b/src/Monkey/Performance/PerformanceTracker.php
index 3438f11..32a242c 100644
--- a/src/Monkey/Performance/PerformanceTracker.php
+++ b/src/Monkey/Performance/PerformanceTracker.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Performance;
+namespace MonkeyLang\Monkey\Performance;
 
 use RuntimeException;
 
diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 2806cc8..ab44c64 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -2,19 +2,19 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Monkey\Repl;
-
-use Monkey\Evaluator\Environment;
-use Monkey\Evaluator\Evaluator;
-use Monkey\Lexer\Lexer;
-use Monkey\Monkey\Config\Configuration;
-use Monkey\Monkey\Exceptions\MonkeyRuntimeException;
-use Monkey\Monkey\IO\InputReader;
-use Monkey\Monkey\IO\OutputFormatter;
-use Monkey\Monkey\Performance\PerformanceTracker;
-use Monkey\Object\MonkeyObject;
-use Monkey\Parser\Parser;
-use Monkey\Parser\ProgramParser;
+namespace MonkeyLang\Monkey\Repl;
+
+use MonkeyLang\Evaluator\Environment;
+use MonkeyLang\Evaluator\Evaluator;
+use MonkeyLang\Lexer\Lexer;
+use MonkeyLang\Monkey\Config\Configuration;
+use MonkeyLang\Monkey\Exceptions\MonkeyRuntimeException;
+use MonkeyLang\Monkey\IO\InputReader;
+use MonkeyLang\Monkey\IO\OutputFormatter;
+use MonkeyLang\Monkey\Performance\PerformanceTracker;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\ProgramParser;
 use Throwable;
 
 use const PHP_OS_FAMILY;
diff --git a/src/Object/ArrayObject.php b/src/Object/ArrayObject.php
index 910f09c..2f5cac3 100644
--- a/src/Object/ArrayObject.php
+++ b/src/Object/ArrayObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 use function count;
 use function sprintf;
diff --git a/src/Object/BooleanObject.php b/src/Object/BooleanObject.php
index b489237..79a9382 100644
--- a/src/Object/BooleanObject.php
+++ b/src/Object/BooleanObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 final readonly class BooleanObject extends MonkeyObject
 {
diff --git a/src/Object/BuiltinFunctionObject.php b/src/Object/BuiltinFunctionObject.php
index 87cb2af..6d2708c 100644
--- a/src/Object/BuiltinFunctionObject.php
+++ b/src/Object/BuiltinFunctionObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 use Closure;
 
diff --git a/src/Object/ErrorObject.php b/src/Object/ErrorObject.php
index 108fe88..7331a56 100644
--- a/src/Object/ErrorObject.php
+++ b/src/Object/ErrorObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 use function sprintf;
 
diff --git a/src/Object/FloatObject.php b/src/Object/FloatObject.php
index b219a44..206bbcd 100644
--- a/src/Object/FloatObject.php
+++ b/src/Object/FloatObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 use function sprintf;
 
diff --git a/src/Object/FunctionObject.php b/src/Object/FunctionObject.php
index fa2e0be..6aba678 100644
--- a/src/Object/FunctionObject.php
+++ b/src/Object/FunctionObject.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Evaluator\Environment;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Evaluator\Environment;
 
 use function sprintf;
 
diff --git a/src/Object/IntegerObject.php b/src/Object/IntegerObject.php
index 20a514c..59dbbfa 100644
--- a/src/Object/IntegerObject.php
+++ b/src/Object/IntegerObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 use function sprintf;
 
diff --git a/src/Object/MonkeyObject.php b/src/Object/MonkeyObject.php
index 644bf1b..1c1954f 100644
--- a/src/Object/MonkeyObject.php
+++ b/src/Object/MonkeyObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 abstract readonly class MonkeyObject
 {
diff --git a/src/Object/MonkeyObjectType.php b/src/Object/MonkeyObjectType.php
index 24804cf..867388d 100644
--- a/src/Object/MonkeyObjectType.php
+++ b/src/Object/MonkeyObjectType.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 enum MonkeyObjectType: int
 {
diff --git a/src/Object/NullObject.php b/src/Object/NullObject.php
index 56a85d8..fbec8f3 100644
--- a/src/Object/NullObject.php
+++ b/src/Object/NullObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 final readonly class NullObject extends MonkeyObject
 {
diff --git a/src/Object/ReturnValueObject.php b/src/Object/ReturnValueObject.php
index eb1ad60..fa631f1 100644
--- a/src/Object/ReturnValueObject.php
+++ b/src/Object/ReturnValueObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 final readonly class ReturnValueObject extends MonkeyObject
 {
diff --git a/src/Object/StringObject.php b/src/Object/StringObject.php
index 7dae9d3..9ebafa3 100644
--- a/src/Object/StringObject.php
+++ b/src/Object/StringObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Object;
+namespace MonkeyLang\Object;
 
 final readonly class StringObject extends MonkeyObject
 {
diff --git a/src/Parser/ExpressionListParser.php b/src/Parser/ExpressionListParser.php
index 0a39392..730fd94 100644
--- a/src/Parser/ExpressionListParser.php
+++ b/src/Parser/ExpressionListParser.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser;
+namespace MonkeyLang\Parser;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Token\TokenType;
 
 final class ExpressionListParser
 {
diff --git a/src/Parser/FunctionParametersParser.php b/src/Parser/FunctionParametersParser.php
index af11af3..a56783a 100644
--- a/src/Parser/FunctionParametersParser.php
+++ b/src/Parser/FunctionParametersParser.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser;
+namespace MonkeyLang\Parser;
 
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Token\TokenType;
 
 final class FunctionParametersParser
 {
diff --git a/src/Parser/Parselet/ArrayParselet.php b/src/Parser/Parselet/ArrayParselet.php
index 0e5909f..8e5b851 100644
--- a/src/Parser/Parselet/ArrayParselet.php
+++ b/src/Parser/Parselet/ArrayParselet.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Types\ArrayLiteral;
-use Monkey\Parser\ExpressionListParser;
-use Monkey\Parser\Parser;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Parser\ExpressionListParser;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Token\TokenType;
 
 final readonly class ArrayParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/BinaryOperatorParselet.php b/src/Parser/Parselet/BinaryOperatorParselet.php
index 0522202..2436183 100644
--- a/src/Parser/Parselet/BinaryOperatorParselet.php
+++ b/src/Parser/Parselet/BinaryOperatorParselet.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\BinaryExpression;
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Parser\Parser;
+use MonkeyLang\Ast\Expressions\BinaryExpression;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Parser\Parser;
 
 final readonly class BinaryOperatorParselet implements InfixParselet
 {
diff --git a/src/Parser/Parselet/CallExpressionParselet.php b/src/Parser/Parselet/CallExpressionParselet.php
index c4b5240..62469a0 100644
--- a/src/Parser/Parselet/CallExpressionParselet.php
+++ b/src/Parser/Parselet/CallExpressionParselet.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\CallExpression;
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Parser\ExpressionListParser;
-use Monkey\Parser\Parser;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\CallExpression;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Parser\ExpressionListParser;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Token\TokenType;
 
 final readonly class CallExpressionParselet implements InfixParselet
 {
diff --git a/src/Parser/Parselet/FunctionLiteralParselet.php b/src/Parser/Parselet/FunctionLiteralParselet.php
index efe45a4..5b1e734 100644
--- a/src/Parser/Parselet/FunctionLiteralParselet.php
+++ b/src/Parser/Parselet/FunctionLiteralParselet.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
-
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Types\FunctionLiteral;
-use Monkey\Parser\FunctionParametersParser;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Statements\BlockStatementParser;
-use Monkey\Token\TokenType;
+namespace MonkeyLang\Parser\Parselet;
+
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Types\FunctionLiteral;
+use MonkeyLang\Parser\FunctionParametersParser;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Statements\BlockStatementParser;
+use MonkeyLang\Token\TokenType;
 
 final readonly class FunctionLiteralParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/GroupedExpressionParselet.php b/src/Parser/Parselet/GroupedExpressionParselet.php
index 979d1da..0a7e0bf 100644
--- a/src/Parser/Parselet/GroupedExpressionParselet.php
+++ b/src/Parser/Parselet/GroupedExpressionParselet.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Token\TokenType;
 
 final readonly class GroupedExpressionParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/IdentifierParselet.php b/src/Parser/Parselet/IdentifierParselet.php
index 5327fa0..101562d 100644
--- a/src/Parser/Parselet/IdentifierParselet.php
+++ b/src/Parser/Parselet/IdentifierParselet.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Parser\Parser;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Parser\Parser;
 
 final readonly class IdentifierParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/IfExpressionParselet.php b/src/Parser/Parselet/IfExpressionParselet.php
index 1892e88..3210176 100644
--- a/src/Parser/Parselet/IfExpressionParselet.php
+++ b/src/Parser/Parselet/IfExpressionParselet.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
-
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IfExpression;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Parser\Statements\BlockStatementParser;
-use Monkey\Token\TokenType;
+namespace MonkeyLang\Parser\Parselet;
+
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IfExpression;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Parser\Statements\BlockStatementParser;
+use MonkeyLang\Token\TokenType;
 
 final readonly class IfExpressionParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/IndexExpressionParselet.php b/src/Parser/Parselet/IndexExpressionParselet.php
index 49eaf47..70e544c 100644
--- a/src/Parser/Parselet/IndexExpressionParselet.php
+++ b/src/Parser/Parselet/IndexExpressionParselet.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IndexExpression;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Token\TokenType;
 
 final readonly class IndexExpressionParselet implements InfixParselet
 {
diff --git a/src/Parser/Parselet/InfixParselet.php b/src/Parser/Parselet/InfixParselet.php
index 47270a7..ed723a6 100644
--- a/src/Parser/Parselet/InfixParselet.php
+++ b/src/Parser/Parselet/InfixParselet.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\Expression;
 
 interface InfixParselet
 {
diff --git a/src/Parser/Parselet/PostfixOperatorParselet.php b/src/Parser/Parselet/PostfixOperatorParselet.php
index e3482a1..4a900ca 100644
--- a/src/Parser/Parselet/PostfixOperatorParselet.php
+++ b/src/Parser/Parselet/PostfixOperatorParselet.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\PostfixExpression;
-use Monkey\Parser\Parser;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Parser\Parser;
 
 final readonly class PostfixOperatorParselet implements PostfixParselet
 {
diff --git a/src/Parser/Parselet/PostfixParselet.php b/src/Parser/Parselet/PostfixParselet.php
index 268cb7f..151830c 100644
--- a/src/Parser/Parselet/PostfixParselet.php
+++ b/src/Parser/Parselet/PostfixParselet.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\Expression;
 
 interface PostfixParselet
 {
diff --git a/src/Parser/Parselet/PrefixParselet.php b/src/Parser/Parselet/PrefixParselet.php
index 6cf005c..66c661a 100644
--- a/src/Parser/Parselet/PrefixParselet.php
+++ b/src/Parser/Parselet/PrefixParselet.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\Expression;
 
 interface PrefixParselet
 {
diff --git a/src/Parser/Parselet/ScalarParselet.php b/src/Parser/Parselet/ScalarParselet.php
index b2de936..4a12258 100644
--- a/src/Parser/Parselet/ScalarParselet.php
+++ b/src/Parser/Parselet/ScalarParselet.php
@@ -2,16 +2,16 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
 use InvalidArgumentException;
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Types\BooleanLiteral;
-use Monkey\Ast\Types\FloatLiteral;
-use Monkey\Ast\Types\IntegerLiteral;
-use Monkey\Ast\Types\StringLiteral;
-use Monkey\Parser\Parser;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Ast\Types\FloatLiteral;
+use MonkeyLang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Ast\Types\StringLiteral;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Token\TokenType;
 
 final class ScalarParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/UnaryOperatorParselet.php b/src/Parser/Parselet/UnaryOperatorParselet.php
index 1baf23a..ed69bc8 100644
--- a/src/Parser/Parselet/UnaryOperatorParselet.php
+++ b/src/Parser/Parselet/UnaryOperatorParselet.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
+namespace MonkeyLang\Parser\Parselet;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\UnaryExpression;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\UnaryExpression;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
 
 final readonly class UnaryOperatorParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/WhileExpressionParselet.php b/src/Parser/Parselet/WhileExpressionParselet.php
index 3033a9f..f8255f4 100644
--- a/src/Parser/Parselet/WhileExpressionParselet.php
+++ b/src/Parser/Parselet/WhileExpressionParselet.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Parselet;
-
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\WhileExpression;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Parser\Statements\BlockStatementParser;
-use Monkey\Token\TokenType;
+namespace MonkeyLang\Parser\Parselet;
+
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Parser\Statements\BlockStatementParser;
+use MonkeyLang\Token\TokenType;
 
 final readonly class WhileExpressionParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parser.php b/src/Parser/Parser.php
index bf9cb48..76e2173 100644
--- a/src/Parser/Parser.php
+++ b/src/Parser/Parser.php
@@ -2,27 +2,27 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser;
-
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Lexer\Lexer;
-use Monkey\Parser\Parselet\ArrayParselet;
-use Monkey\Parser\Parselet\BinaryOperatorParselet;
-use Monkey\Parser\Parselet\CallExpressionParselet;
-use Monkey\Parser\Parselet\FunctionLiteralParselet;
-use Monkey\Parser\Parselet\GroupedExpressionParselet;
-use Monkey\Parser\Parselet\IdentifierParselet;
-use Monkey\Parser\Parselet\IfExpressionParselet;
-use Monkey\Parser\Parselet\IndexExpressionParselet;
-use Monkey\Parser\Parselet\InfixParselet;
-use Monkey\Parser\Parselet\PostfixOperatorParselet;
-use Monkey\Parser\Parselet\PostfixParselet;
-use Monkey\Parser\Parselet\PrefixParselet;
-use Monkey\Parser\Parselet\ScalarParselet;
-use Monkey\Parser\Parselet\UnaryOperatorParselet;
-use Monkey\Parser\Parselet\WhileExpressionParselet;
-use Monkey\Token\Token;
-use Monkey\Token\TokenType;
+namespace MonkeyLang\Parser;
+
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Lexer\Lexer;
+use MonkeyLang\Parser\Parselet\ArrayParselet;
+use MonkeyLang\Parser\Parselet\BinaryOperatorParselet;
+use MonkeyLang\Parser\Parselet\CallExpressionParselet;
+use MonkeyLang\Parser\Parselet\FunctionLiteralParselet;
+use MonkeyLang\Parser\Parselet\GroupedExpressionParselet;
+use MonkeyLang\Parser\Parselet\IdentifierParselet;
+use MonkeyLang\Parser\Parselet\IfExpressionParselet;
+use MonkeyLang\Parser\Parselet\IndexExpressionParselet;
+use MonkeyLang\Parser\Parselet\InfixParselet;
+use MonkeyLang\Parser\Parselet\PostfixOperatorParselet;
+use MonkeyLang\Parser\Parselet\PostfixParselet;
+use MonkeyLang\Parser\Parselet\PrefixParselet;
+use MonkeyLang\Parser\Parselet\ScalarParselet;
+use MonkeyLang\Parser\Parselet\UnaryOperatorParselet;
+use MonkeyLang\Parser\Parselet\WhileExpressionParselet;
+use MonkeyLang\Token\Token;
+use MonkeyLang\Token\TokenType;
 
 use function sprintf;
 
diff --git a/src/Parser/Precedence.php b/src/Parser/Precedence.php
index 3f7ecd0..9fd734f 100644
--- a/src/Parser/Precedence.php
+++ b/src/Parser/Precedence.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser;
+namespace MonkeyLang\Parser;
 
 enum Precedence: int
 {
diff --git a/src/Parser/ProgramParser.php b/src/Parser/ProgramParser.php
index 2b0a070..1e988b8 100644
--- a/src/Parser/ProgramParser.php
+++ b/src/Parser/ProgramParser.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser;
+namespace MonkeyLang\Parser;
 
-use Monkey\Ast\Program;
-use Monkey\Ast\Statements\Statement;
-use Monkey\Parser\Statements\StatementParser;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Program;
+use MonkeyLang\Ast\Statements\Statement;
+use MonkeyLang\Parser\Statements\StatementParser;
+use MonkeyLang\Token\TokenType;
 
 final class ProgramParser
 {
diff --git a/src/Parser/Statements/AssignStatementParser.php b/src/Parser/Statements/AssignStatementParser.php
index 6ae964d..a51b524 100644
--- a/src/Parser/Statements/AssignStatementParser.php
+++ b/src/Parser/Statements/AssignStatementParser.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Statements;
-
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Ast\Statements\AssignStatement;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Token\TokenType;
+namespace MonkeyLang\Parser\Statements;
+
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Ast\Statements\AssignStatement;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Token\TokenType;
 
 final class AssignStatementParser
 {
diff --git a/src/Parser/Statements/BlockStatementParser.php b/src/Parser/Statements/BlockStatementParser.php
index 96164f4..85bddd1 100644
--- a/src/Parser/Statements/BlockStatementParser.php
+++ b/src/Parser/Statements/BlockStatementParser.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Statements;
+namespace MonkeyLang\Parser\Statements;
 
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Ast\Statements\Statement;
-use Monkey\Parser\Parser;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Ast\Statements\Statement;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Token\TokenType;
 
 final class BlockStatementParser
 {
diff --git a/src/Parser/Statements/ExpressionStatementParser.php b/src/Parser/Statements/ExpressionStatementParser.php
index 25b06e4..6181b64 100644
--- a/src/Parser/Statements/ExpressionStatementParser.php
+++ b/src/Parser/Statements/ExpressionStatementParser.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Statements;
+namespace MonkeyLang\Parser\Statements;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Statements\ExpressionStatement;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Statements\ExpressionStatement;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Token\TokenType;
 
 final class ExpressionStatementParser
 {
diff --git a/src/Parser/Statements/LetStatementParser.php b/src/Parser/Statements/LetStatementParser.php
index 7001b29..01180f2 100644
--- a/src/Parser/Statements/LetStatementParser.php
+++ b/src/Parser/Statements/LetStatementParser.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Statements;
-
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Ast\Statements\LetStatement;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Token\TokenType;
+namespace MonkeyLang\Parser\Statements;
+
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Ast\Statements\LetStatement;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Token\TokenType;
 
 final class LetStatementParser
 {
diff --git a/src/Parser/Statements/ReturnStatementParser.php b/src/Parser/Statements/ReturnStatementParser.php
index 1c0edf7..c6f7b32 100644
--- a/src/Parser/Statements/ReturnStatementParser.php
+++ b/src/Parser/Statements/ReturnStatementParser.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Statements;
+namespace MonkeyLang\Parser\Statements;
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Statements\ReturnStatement;
-use Monkey\Parser\Parser;
-use Monkey\Parser\Precedence;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Token\TokenType;
 
 final class ReturnStatementParser
 {
diff --git a/src/Parser/Statements/StatementParser.php b/src/Parser/Statements/StatementParser.php
index 7b0e6a0..4614e25 100644
--- a/src/Parser/Statements/StatementParser.php
+++ b/src/Parser/Statements/StatementParser.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Parser\Statements;
+namespace MonkeyLang\Parser\Statements;
 
-use Monkey\Ast\Statements\Statement;
-use Monkey\Parser\Parser;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Statements\Statement;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Token\TokenType;
 
 final class StatementParser
 {
diff --git a/src/Support/StringBuilder.php b/src/Support/StringBuilder.php
index c9dcff9..9181a5a 100644
--- a/src/Support/StringBuilder.php
+++ b/src/Support/StringBuilder.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Support;
+namespace MonkeyLang\Support;
 
 use Stringable;
 
diff --git a/src/Token/Token.php b/src/Token/Token.php
index a9d6075..40d0f41 100644
--- a/src/Token/Token.php
+++ b/src/Token/Token.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Token;
+namespace MonkeyLang\Token;
 
 final readonly class Token
 {
diff --git a/src/Token/TokenType.php b/src/Token/TokenType.php
index 595d723..ef5f8f6 100644
--- a/src/Token/TokenType.php
+++ b/src/Token/TokenType.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace Monkey\Token;
+namespace MonkeyLang\Token;
 
-use Monkey\Lexer\Char;
-use Monkey\Parser\Precedence;
+use MonkeyLang\Lexer\Char;
+use MonkeyLang\Parser\Precedence;
 
 enum TokenType: int
 {
diff --git a/tests/AstTest.php b/tests/AstTest.php
index 99c85ae..8de3107 100644
--- a/tests/AstTest.php
+++ b/tests/AstTest.php
@@ -4,12 +4,12 @@
 
 namespace Tests;
 
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Ast\Program;
-use Monkey\Ast\Statements\LetStatement;
-use Monkey\Ast\Types\IntegerLiteral;
-use Monkey\Token\Token;
-use Monkey\Token\TokenType;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Ast\Program;
+use MonkeyLang\Ast\Statements\LetStatement;
+use MonkeyLang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Token\Token;
+use MonkeyLang\Token\TokenType;
 
 test('to string', function () {
     $program = new Program();
diff --git a/tests/EvaluatorTest.php b/tests/EvaluatorTest.php
index 7b88429..f3f5441 100644
--- a/tests/EvaluatorTest.php
+++ b/tests/EvaluatorTest.php
@@ -4,16 +4,16 @@
 
 namespace Tests;
 
-use Monkey\Object\ArrayObject;
-use Monkey\Object\BooleanObject;
-use Monkey\Object\ErrorObject;
-use Monkey\Object\FloatObject;
-use Monkey\Object\FunctionObject;
-use Monkey\Object\IntegerObject;
-use Monkey\Object\MonkeyObject;
-use Monkey\Object\MonkeyObjectType;
-use Monkey\Object\NullObject;
-use Monkey\Object\StringObject;
+use MonkeyLang\Object\ArrayObject;
+use MonkeyLang\Object\BooleanObject;
+use MonkeyLang\Object\ErrorObject;
+use MonkeyLang\Object\FloatObject;
+use MonkeyLang\Object\FunctionObject;
+use MonkeyLang\Object\IntegerObject;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Object\MonkeyObjectType;
+use MonkeyLang\Object\NullObject;
+use MonkeyLang\Object\StringObject;
 
 function testObjectValue(MonkeyObject $object, $expected)
 {
diff --git a/tests/Helpers.php b/tests/Helpers.php
index 3769c6a..47ba4a9 100644
--- a/tests/Helpers.php
+++ b/tests/Helpers.php
@@ -2,16 +2,16 @@
 
 declare(strict_types=1);
 
-use Monkey\Ast\Expressions\Expression;
-use Monkey\Ast\Program;
-use Monkey\Ast\Types\BooleanLiteral;
-use Monkey\Ast\Types\IntegerLiteral;
-use Monkey\Evaluator\Environment;
-use Monkey\Evaluator\Evaluator;
-use Monkey\Lexer\Lexer;
-use Monkey\Object\MonkeyObject;
-use Monkey\Parser\Parser;
-use Monkey\Parser\ProgramParser;
+use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Ast\Program;
+use MonkeyLang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Evaluator\Environment;
+use MonkeyLang\Evaluator\Evaluator;
+use MonkeyLang\Lexer\Lexer;
+use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Parser\Parser;
+use MonkeyLang\Parser\ProgramParser;
 
 function assertInfixExpression(Expression $expression, $leftValue, string $operator, $rightValue): void
 {
diff --git a/tests/LexerTest.php b/tests/LexerTest.php
index 915829f..1cc1e06 100644
--- a/tests/LexerTest.php
+++ b/tests/LexerTest.php
@@ -4,8 +4,8 @@
 
 namespace Tests;
 
-use Monkey\Lexer\Lexer;
-use Monkey\Token\TokenType;
+use MonkeyLang\Lexer\Lexer;
+use MonkeyLang\Token\TokenType;
 
 test('basic tokens', function () {
     $input = <<<MONKEY
diff --git a/tests/ParserTest.php b/tests/ParserTest.php
index b45c292..95f26d5 100644
--- a/tests/ParserTest.php
+++ b/tests/ParserTest.php
@@ -4,24 +4,24 @@
 
 namespace Tests;
 
-use Monkey\Ast\Expressions\BinaryExpression;
-use Monkey\Ast\Expressions\CallExpression;
-use Monkey\Ast\Expressions\IdentifierExpression;
-use Monkey\Ast\Expressions\IfExpression;
-use Monkey\Ast\Expressions\IndexExpression;
-use Monkey\Ast\Expressions\PostfixExpression;
-use Monkey\Ast\Expressions\UnaryExpression;
-use Monkey\Ast\Expressions\WhileExpression;
-use Monkey\Ast\Statements\AssignStatement;
-use Monkey\Ast\Statements\BlockStatement;
-use Monkey\Ast\Statements\ExpressionStatement;
-use Monkey\Ast\Statements\LetStatement;
-use Monkey\Ast\Statements\ReturnStatement;
-use Monkey\Ast\Types\ArrayLiteral;
-use Monkey\Ast\Types\BooleanLiteral;
-use Monkey\Ast\Types\FunctionLiteral;
-use Monkey\Ast\Types\IntegerLiteral;
-use Monkey\Ast\Types\StringLiteral;
+use MonkeyLang\Ast\Expressions\BinaryExpression;
+use MonkeyLang\Ast\Expressions\CallExpression;
+use MonkeyLang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Ast\Expressions\IfExpression;
+use MonkeyLang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Ast\Expressions\UnaryExpression;
+use MonkeyLang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Ast\Statements\AssignStatement;
+use MonkeyLang\Ast\Statements\BlockStatement;
+use MonkeyLang\Ast\Statements\ExpressionStatement;
+use MonkeyLang\Ast\Statements\LetStatement;
+use MonkeyLang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Ast\Types\FunctionLiteral;
+use MonkeyLang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Ast\Types\StringLiteral;
 
 test('let statements', function (string $input, string $name, $value) {
     $program = newProgram($input);

From 1c3077df3d500f6db2b92139077c6d4068d73b8c Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 12:36:42 -0300
Subject: [PATCH 06/22] Update .gitignore

---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 0065076..fdb64ef 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@
 .DS_Store
 composer.lock
 .php-cs-fixer.cache
+/.phpunit.cache/

From 0733f63aadbe3e1659aa1ec6b95a6fa52748a2ec Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 12:46:22 -0300
Subject: [PATCH 07/22] Namespace

---
 .../Ast/Expressions/BinaryExpression.php      |  6 +-
 .../Ast/Expressions/CallExpression.php        |  6 +-
 src/{ => Lang}/Ast/Expressions/Expression.php |  4 +-
 .../Ast/Expressions/IdentifierExpression.php  |  4 +-
 .../Ast/Expressions/IfExpression.php          |  8 +-
 .../Ast/Expressions/IndexExpression.php       |  6 +-
 .../Ast/Expressions/PostfixExpression.php     |  6 +-
 .../Ast/Expressions/UnaryExpression.php       |  6 +-
 .../Ast/Expressions/WhileExpression.php       |  8 +-
 src/{ => Lang}/Ast/Node.php                   |  2 +-
 src/{ => Lang}/Ast/Program.php                |  7 +-
 .../Ast/Statements/AssignStatement.php        | 10 +--
 .../Ast/Statements/BlockStatement.php         |  6 +-
 .../Ast/Statements/ExpressionStatement.php    |  6 +-
 .../Ast/Statements/LetStatement.php           | 10 +--
 .../Ast/Statements/ReturnStatement.php        |  8 +-
 src/{ => Lang}/Ast/Statements/Statement.php   |  4 +-
 src/{ => Lang}/Ast/Types/ArrayLiteral.php     |  8 +-
 src/{ => Lang}/Ast/Types/BooleanLiteral.php   |  6 +-
 src/{ => Lang}/Ast/Types/FloatLiteral.php     |  6 +-
 src/{ => Lang}/Ast/Types/FunctionLiteral.php  | 12 +--
 src/{ => Lang}/Ast/Types/IntegerLiteral.php   |  6 +-
 src/{ => Lang}/Ast/Types/StringLiteral.php    |  6 +-
 .../Evaluator/Builtin/EvalBuiltinFunction.php |  6 +-
 .../Evaluator/Builtin/EvalFirstFunction.php   | 10 +--
 .../Evaluator/Builtin/EvalLastFunction.php    | 10 +--
 .../Evaluator/Builtin/EvalLenFunction.php     | 12 +--
 .../Evaluator/Builtin/EvalMapFunction.php     | 12 +--
 .../Evaluator/Builtin/EvalPushFunction.php    |  8 +-
 .../Evaluator/Builtin/EvalPutsFunction.php    |  8 +-
 .../Evaluator/Builtin/EvalSliceFunction.php   | 12 +--
 src/{ => Lang}/Evaluator/BuiltinFunction.php  |  6 +-
 src/{ => Lang}/Evaluator/Environment.php      |  4 +-
 .../Evaluator/EvalArrayBinaryExpression.php   |  8 +-
 src/{ => Lang}/Evaluator/EvalArrayLiteral.php | 10 +--
 .../Evaluator/EvalAssingStatement.php         |  8 +-
 .../Evaluator/EvalBinaryExpression.php        | 18 ++---
 .../Evaluator/EvalBlockStatement.php          | 12 +--
 .../Evaluator/EvalCallExpression.php          | 16 ++--
 src/{ => Lang}/Evaluator/EvalIdentifier.php   |  8 +-
 src/{ => Lang}/Evaluator/EvalIfExpression.php | 12 +--
 .../Evaluator/EvalIndexExpression.php         | 16 ++--
 src/{ => Lang}/Evaluator/EvalLetStatement.php |  8 +-
 .../EvalMinusUnaryOperatorExpression.php      |  8 +-
 .../Evaluator/EvalNotOperatorExpression.php   |  8 +-
 .../Evaluator/EvalNumericBinaryExpression.php |  8 +-
 .../Evaluator/EvalPostfixExpression.php       | 10 +--
 src/{ => Lang}/Evaluator/EvalProgram.php      | 12 +--
 .../Evaluator/EvalReturnStatement.php         | 10 +--
 .../Evaluator/EvalStringBinaryExpression.php  | 10 +--
 .../Evaluator/EvalUnaryExpression.php         |  6 +-
 .../Evaluator/EvalWhileExpression.php         | 10 +--
 src/{ => Lang}/Evaluator/Evaluator.php        | 76 +++++++++----------
 src/{ => Lang}/Lexer/Char.php                 |  2 +-
 src/{ => Lang}/Lexer/Input.php                |  2 +-
 src/{ => Lang}/Lexer/Lexer.php                |  6 +-
 src/{ => Lang}/Object/ArrayObject.php         |  2 +-
 src/{ => Lang}/Object/BooleanObject.php       |  2 +-
 .../Object/BuiltinFunctionObject.php          |  2 +-
 src/{ => Lang}/Object/ErrorObject.php         |  2 +-
 src/{ => Lang}/Object/FloatObject.php         |  2 +-
 src/{ => Lang}/Object/FunctionObject.php      |  8 +-
 src/{ => Lang}/Object/IntegerObject.php       |  2 +-
 src/{ => Lang}/Object/MonkeyObject.php        |  2 +-
 src/{ => Lang}/Object/MonkeyObjectType.php    |  2 +-
 src/{ => Lang}/Object/NullObject.php          |  2 +-
 src/{ => Lang}/Object/ReturnValueObject.php   |  2 +-
 src/{ => Lang}/Object/StringObject.php        |  2 +-
 .../Parser/ExpressionListParser.php           |  6 +-
 .../Parser/FunctionParametersParser.php       |  6 +-
 .../Parser/Parselet/ArrayParselet.php         | 12 +--
 .../Parselet/BinaryOperatorParselet.php       |  8 +-
 .../Parselet/CallExpressionParselet.php       | 12 +--
 .../Parselet/FunctionLiteralParselet.php      | 16 ++--
 .../Parselet/GroupedExpressionParselet.php    | 10 +--
 .../Parser/Parselet/IdentifierParselet.php    |  8 +-
 .../Parser/Parselet/IfExpressionParselet.php  | 16 ++--
 .../Parselet/IndexExpressionParselet.php      | 12 +--
 .../Parser/Parselet/InfixParselet.php         |  4 +-
 .../Parselet/PostfixOperatorParselet.php      |  8 +-
 .../Parser/Parselet/PostfixParselet.php       |  4 +-
 .../Parser/Parselet/PrefixParselet.php        |  4 +-
 .../Parser/Parselet/ScalarParselet.php        | 16 ++--
 .../Parser/Parselet/UnaryOperatorParselet.php | 10 +--
 .../Parselet/WhileExpressionParselet.php      | 16 ++--
 src/{ => Lang}/Parser/Parser.php              | 42 +++++-----
 src/{ => Lang}/Parser/Precedence.php          |  2 +-
 src/{ => Lang}/Parser/ProgramParser.php       | 10 +--
 .../Statements/AssignStatementParser.php      | 16 ++--
 .../Statements/BlockStatementParser.php       | 10 +--
 .../Statements/ExpressionStatementParser.php  | 12 +--
 .../Parser/Statements/LetStatementParser.php  | 16 ++--
 .../Statements/ReturnStatementParser.php      | 12 +--
 .../Parser/Statements/StatementParser.php     |  8 +-
 src/{ => Lang}/Support/StringBuilder.php      |  2 +-
 src/{ => Lang}/Token/Token.php                |  2 +-
 src/{ => Lang}/Token/TokenType.php            |  6 +-
 src/Monkey/Command/RunFileCommand.php         | 12 +--
 src/Monkey/IO/OutputFormatter.php             |  4 +-
 src/Monkey/Repl/ReplManager.php               | 12 +--
 tests/AstTest.php                             | 12 +--
 tests/EvaluatorTest.php                       | 20 ++---
 tests/Helpers.php                             | 20 ++---
 tests/LexerTest.php                           |  4 +-
 tests/ParserTest.php                          | 36 ++++-----
 105 files changed, 489 insertions(+), 490 deletions(-)
 rename src/{ => Lang}/Ast/Expressions/BinaryExpression.php (84%)
 rename src/{ => Lang}/Ast/Expressions/CallExpression.php (86%)
 rename src/{ => Lang}/Ast/Expressions/Expression.php (51%)
 rename src/{ => Lang}/Ast/Expressions/IdentifierExpression.php (79%)
 rename src/{ => Lang}/Ast/Expressions/IfExpression.php (81%)
 rename src/{ => Lang}/Ast/Expressions/IndexExpression.php (81%)
 rename src/{ => Lang}/Ast/Expressions/PostfixExpression.php (79%)
 rename src/{ => Lang}/Ast/Expressions/UnaryExpression.php (80%)
 rename src/{ => Lang}/Ast/Expressions/WhileExpression.php (74%)
 rename src/{ => Lang}/Ast/Node.php (88%)
 rename src/{ => Lang}/Ast/Program.php (87%)
 rename src/{ => Lang}/Ast/Statements/AssignStatement.php (70%)
 rename src/{ => Lang}/Ast/Statements/BlockStatement.php (82%)
 rename src/{ => Lang}/Ast/Statements/ExpressionStatement.php (72%)
 rename src/{ => Lang}/Ast/Statements/LetStatement.php (72%)
 rename src/{ => Lang}/Ast/Statements/ReturnStatement.php (75%)
 rename src/{ => Lang}/Ast/Statements/Statement.php (51%)
 rename src/{ => Lang}/Ast/Types/ArrayLiteral.php (80%)
 rename src/{ => Lang}/Ast/Types/BooleanLiteral.php (71%)
 rename src/{ => Lang}/Ast/Types/FloatLiteral.php (71%)
 rename src/{ => Lang}/Ast/Types/FunctionLiteral.php (74%)
 rename src/{ => Lang}/Ast/Types/IntegerLiteral.php (71%)
 rename src/{ => Lang}/Ast/Types/StringLiteral.php (71%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalBuiltinFunction.php (66%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalFirstFunction.php (76%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalLastFunction.php (76%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalLenFunction.php (73%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalMapFunction.php (83%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalPushFunction.php (79%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalPutsFunction.php (75%)
 rename src/{ => Lang}/Evaluator/Builtin/EvalSliceFunction.php (86%)
 rename src/{ => Lang}/Evaluator/BuiltinFunction.php (77%)
 rename src/{ => Lang}/Evaluator/Environment.php (85%)
 rename src/{ => Lang}/Evaluator/EvalArrayBinaryExpression.php (74%)
 rename src/{ => Lang}/Evaluator/EvalArrayLiteral.php (73%)
 rename src/{ => Lang}/Evaluator/EvalAssingStatement.php (82%)
 rename src/{ => Lang}/Evaluator/EvalBinaryExpression.php (83%)
 rename src/{ => Lang}/Evaluator/EvalBlockStatement.php (73%)
 rename src/{ => Lang}/Evaluator/EvalCallExpression.php (87%)
 rename src/{ => Lang}/Evaluator/EvalIdentifier.php (75%)
 rename src/{ => Lang}/Evaluator/EvalIfExpression.php (76%)
 rename src/{ => Lang}/Evaluator/EvalIndexExpression.php (75%)
 rename src/{ => Lang}/Evaluator/EvalLetStatement.php (79%)
 rename src/{ => Lang}/Evaluator/EvalMinusUnaryOperatorExpression.php (70%)
 rename src/{ => Lang}/Evaluator/EvalNotOperatorExpression.php (72%)
 rename src/{ => Lang}/Evaluator/EvalNumericBinaryExpression.php (88%)
 rename src/{ => Lang}/Evaluator/EvalPostfixExpression.php (86%)
 rename src/{ => Lang}/Evaluator/EvalProgram.php (74%)
 rename src/{ => Lang}/Evaluator/EvalReturnStatement.php (71%)
 rename src/{ => Lang}/Evaluator/EvalStringBinaryExpression.php (74%)
 rename src/{ => Lang}/Evaluator/EvalUnaryExpression.php (82%)
 rename src/{ => Lang}/Evaluator/EvalWhileExpression.php (80%)
 rename src/{ => Lang}/Evaluator/Evaluator.php (66%)
 rename src/{ => Lang}/Lexer/Char.php (97%)
 rename src/{ => Lang}/Lexer/Input.php (94%)
 rename src/{ => Lang}/Lexer/Lexer.php (97%)
 rename src/{ => Lang}/Object/ArrayObject.php (96%)
 rename src/{ => Lang}/Object/BooleanObject.php (95%)
 rename src/{ => Lang}/Object/BuiltinFunctionObject.php (93%)
 rename src/{ => Lang}/Object/ErrorObject.php (97%)
 rename src/{ => Lang}/Object/FloatObject.php (93%)
 rename src/{ => Lang}/Object/FunctionObject.php (83%)
 rename src/{ => Lang}/Object/IntegerObject.php (93%)
 rename src/{ => Lang}/Object/MonkeyObject.php (95%)
 rename src/{ => Lang}/Object/MonkeyObjectType.php (96%)
 rename src/{ => Lang}/Object/NullObject.php (93%)
 rename src/{ => Lang}/Object/ReturnValueObject.php (93%)
 rename src/{ => Lang}/Object/StringObject.php (94%)
 rename src/{ => Lang}/Parser/ExpressionListParser.php (86%)
 rename src/{ => Lang}/Parser/FunctionParametersParser.php (87%)
 rename src/{ => Lang}/Parser/Parselet/ArrayParselet.php (61%)
 rename src/{ => Lang}/Parser/Parselet/BinaryOperatorParselet.php (75%)
 rename src/{ => Lang}/Parser/Parselet/CallExpressionParselet.php (63%)
 rename src/{ => Lang}/Parser/Parselet/FunctionLiteralParselet.php (67%)
 rename src/{ => Lang}/Parser/Parselet/GroupedExpressionParselet.php (72%)
 rename src/{ => Lang}/Parser/Parselet/IdentifierParselet.php (65%)
 rename src/{ => Lang}/Parser/Parselet/IfExpressionParselet.php (79%)
 rename src/{ => Lang}/Parser/Parselet/IndexExpressionParselet.php (72%)
 rename src/{ => Lang}/Parser/Parselet/InfixParselet.php (58%)
 rename src/{ => Lang}/Parser/Parselet/PostfixOperatorParselet.php (65%)
 rename src/{ => Lang}/Parser/Parselet/PostfixParselet.php (53%)
 rename src/{ => Lang}/Parser/Parselet/PrefixParselet.php (53%)
 rename src/{ => Lang}/Parser/Parselet/ScalarParselet.php (70%)
 rename src/{ => Lang}/Parser/Parselet/UnaryOperatorParselet.php (69%)
 rename src/{ => Lang}/Parser/Parselet/WhileExpressionParselet.php (73%)
 rename src/{ => Lang}/Parser/Parser.php (85%)
 rename src/{ => Lang}/Parser/Precedence.php (90%)
 rename src/{ => Lang}/Parser/ProgramParser.php (69%)
 rename src/{ => Lang}/Parser/Statements/AssignStatementParser.php (66%)
 rename src/{ => Lang}/Parser/Statements/BlockStatementParser.php (75%)
 rename src/{ => Lang}/Parser/Statements/ExpressionStatementParser.php (67%)
 rename src/{ => Lang}/Parser/Statements/LetStatementParser.php (72%)
 rename src/{ => Lang}/Parser/Statements/ReturnStatementParser.php (66%)
 rename src/{ => Lang}/Parser/Statements/StatementParser.php (79%)
 rename src/{ => Lang}/Support/StringBuilder.php (95%)
 rename src/{ => Lang}/Token/Token.php (94%)
 rename src/{ => Lang}/Token/TokenType.php (97%)

diff --git a/src/Ast/Expressions/BinaryExpression.php b/src/Lang/Ast/Expressions/BinaryExpression.php
similarity index 84%
rename from src/Ast/Expressions/BinaryExpression.php
rename to src/Lang/Ast/Expressions/BinaryExpression.php
index 6ca0f8f..c64bcb0 100644
--- a/src/Ast/Expressions/BinaryExpression.php
+++ b/src/Lang/Ast/Expressions/BinaryExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class BinaryExpression extends Expression
 {
diff --git a/src/Ast/Expressions/CallExpression.php b/src/Lang/Ast/Expressions/CallExpression.php
similarity index 86%
rename from src/Ast/Expressions/CallExpression.php
rename to src/Lang/Ast/Expressions/CallExpression.php
index ad619fa..5df8885 100644
--- a/src/Ast/Expressions/CallExpression.php
+++ b/src/Lang/Ast/Expressions/CallExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 use function count;
 
diff --git a/src/Ast/Expressions/Expression.php b/src/Lang/Ast/Expressions/Expression.php
similarity index 51%
rename from src/Ast/Expressions/Expression.php
rename to src/Lang/Ast/Expressions/Expression.php
index b95f7e7..c06fe36 100644
--- a/src/Ast/Expressions/Expression.php
+++ b/src/Lang/Ast/Expressions/Expression.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Ast\Node;
+use MonkeyLang\Lang\Ast\Node;
 
 abstract class Expression extends Node
 {
diff --git a/src/Ast/Expressions/IdentifierExpression.php b/src/Lang/Ast/Expressions/IdentifierExpression.php
similarity index 79%
rename from src/Ast/Expressions/IdentifierExpression.php
rename to src/Lang/Ast/Expressions/IdentifierExpression.php
index aba00c2..4a2c92a 100644
--- a/src/Ast/Expressions/IdentifierExpression.php
+++ b/src/Lang/Ast/Expressions/IdentifierExpression.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Token\Token;
 
 final class IdentifierExpression extends Expression
 {
diff --git a/src/Ast/Expressions/IfExpression.php b/src/Lang/Ast/Expressions/IfExpression.php
similarity index 81%
rename from src/Ast/Expressions/IfExpression.php
rename to src/Lang/Ast/Expressions/IfExpression.php
index 0619338..208005b 100644
--- a/src/Ast/Expressions/IfExpression.php
+++ b/src/Lang/Ast/Expressions/IfExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class IfExpression extends Expression
 {
diff --git a/src/Ast/Expressions/IndexExpression.php b/src/Lang/Ast/Expressions/IndexExpression.php
similarity index 81%
rename from src/Ast/Expressions/IndexExpression.php
rename to src/Lang/Ast/Expressions/IndexExpression.php
index 8ee8bdb..fb59af6 100644
--- a/src/Ast/Expressions/IndexExpression.php
+++ b/src/Lang/Ast/Expressions/IndexExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class IndexExpression extends Expression
 {
diff --git a/src/Ast/Expressions/PostfixExpression.php b/src/Lang/Ast/Expressions/PostfixExpression.php
similarity index 79%
rename from src/Ast/Expressions/PostfixExpression.php
rename to src/Lang/Ast/Expressions/PostfixExpression.php
index f06d938..37250c6 100644
--- a/src/Ast/Expressions/PostfixExpression.php
+++ b/src/Lang/Ast/Expressions/PostfixExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class PostfixExpression extends Expression
 {
diff --git a/src/Ast/Expressions/UnaryExpression.php b/src/Lang/Ast/Expressions/UnaryExpression.php
similarity index 80%
rename from src/Ast/Expressions/UnaryExpression.php
rename to src/Lang/Ast/Expressions/UnaryExpression.php
index 0243e9f..d46c754 100644
--- a/src/Ast/Expressions/UnaryExpression.php
+++ b/src/Lang/Ast/Expressions/UnaryExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class UnaryExpression extends Expression
 {
diff --git a/src/Ast/Expressions/WhileExpression.php b/src/Lang/Ast/Expressions/WhileExpression.php
similarity index 74%
rename from src/Ast/Expressions/WhileExpression.php
rename to src/Lang/Ast/Expressions/WhileExpression.php
index dee2e7d..bcda764 100644
--- a/src/Ast/Expressions/WhileExpression.php
+++ b/src/Lang/Ast/Expressions/WhileExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Expressions;
+namespace MonkeyLang\Lang\Ast\Expressions;
 
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class WhileExpression extends Expression
 {
diff --git a/src/Ast/Node.php b/src/Lang/Ast/Node.php
similarity index 88%
rename from src/Ast/Node.php
rename to src/Lang/Ast/Node.php
index a3290c5..7bf07de 100644
--- a/src/Ast/Node.php
+++ b/src/Lang/Ast/Node.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast;
+namespace MonkeyLang\Lang\Ast;
 
 use Stringable;
 
diff --git a/src/Ast/Program.php b/src/Lang/Ast/Program.php
similarity index 87%
rename from src/Ast/Program.php
rename to src/Lang/Ast/Program.php
index f8c0fad..6499464 100644
--- a/src/Ast/Program.php
+++ b/src/Lang/Ast/Program.php
@@ -2,11 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast;
+namespace MonkeyLang\Lang\Ast;
 
-use MonkeyLang\Ast\Statements\Statement;
-
-use MonkeyLang\Support\StringBuilder;
+use MonkeyLang\Lang\Ast\Statements\Statement;
+use MonkeyLang\Lang\Support\StringBuilder;
 
 use function count;
 
diff --git a/src/Ast/Statements/AssignStatement.php b/src/Lang/Ast/Statements/AssignStatement.php
similarity index 70%
rename from src/Ast/Statements/AssignStatement.php
rename to src/Lang/Ast/Statements/AssignStatement.php
index 6439b22..0a739f2 100644
--- a/src/Ast/Statements/AssignStatement.php
+++ b/src/Lang/Ast/Statements/AssignStatement.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Statements;
+namespace MonkeyLang\Lang\Ast\Statements;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class AssignStatement extends Statement
 {
diff --git a/src/Ast/Statements/BlockStatement.php b/src/Lang/Ast/Statements/BlockStatement.php
similarity index 82%
rename from src/Ast/Statements/BlockStatement.php
rename to src/Lang/Ast/Statements/BlockStatement.php
index e50095f..80e8fa6 100644
--- a/src/Ast/Statements/BlockStatement.php
+++ b/src/Lang/Ast/Statements/BlockStatement.php
@@ -4,10 +4,10 @@
 
 namespace MonkeyLang\Ast\Statements;
 
-namespace MonkeyLang\Ast\Statements;
+namespace MonkeyLang\Lang\Ast\Statements;
 
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class BlockStatement extends Statement
 {
diff --git a/src/Ast/Statements/ExpressionStatement.php b/src/Lang/Ast/Statements/ExpressionStatement.php
similarity index 72%
rename from src/Ast/Statements/ExpressionStatement.php
rename to src/Lang/Ast/Statements/ExpressionStatement.php
index b893277..0ad5b30 100644
--- a/src/Ast/Statements/ExpressionStatement.php
+++ b/src/Lang/Ast/Statements/ExpressionStatement.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Statements;
+namespace MonkeyLang\Lang\Ast\Statements;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Token\Token;
 
 final class ExpressionStatement extends Statement
 {
diff --git a/src/Ast/Statements/LetStatement.php b/src/Lang/Ast/Statements/LetStatement.php
similarity index 72%
rename from src/Ast/Statements/LetStatement.php
rename to src/Lang/Ast/Statements/LetStatement.php
index be5c5bf..5aa1ca5 100644
--- a/src/Ast/Statements/LetStatement.php
+++ b/src/Lang/Ast/Statements/LetStatement.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Statements;
+namespace MonkeyLang\Lang\Ast\Statements;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class LetStatement extends Statement
 {
diff --git a/src/Ast/Statements/ReturnStatement.php b/src/Lang/Ast/Statements/ReturnStatement.php
similarity index 75%
rename from src/Ast/Statements/ReturnStatement.php
rename to src/Lang/Ast/Statements/ReturnStatement.php
index a3c70e6..5c73d98 100644
--- a/src/Ast/Statements/ReturnStatement.php
+++ b/src/Lang/Ast/Statements/ReturnStatement.php
@@ -4,11 +4,11 @@
 
 namespace MonkeyLang\Ast\Statements;
 
-namespace MonkeyLang\Ast\Statements;
+namespace MonkeyLang\Lang\Ast\Statements;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 final class ReturnStatement extends Statement
 {
diff --git a/src/Ast/Statements/Statement.php b/src/Lang/Ast/Statements/Statement.php
similarity index 51%
rename from src/Ast/Statements/Statement.php
rename to src/Lang/Ast/Statements/Statement.php
index 6d753d5..39b67a4 100644
--- a/src/Ast/Statements/Statement.php
+++ b/src/Lang/Ast/Statements/Statement.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Statements;
+namespace MonkeyLang\Lang\Ast\Statements;
 
-use MonkeyLang\Ast\Node;
+use MonkeyLang\Lang\Ast\Node;
 
 abstract class Statement extends Node
 {
diff --git a/src/Ast/Types/ArrayLiteral.php b/src/Lang/Ast/Types/ArrayLiteral.php
similarity index 80%
rename from src/Ast/Types/ArrayLiteral.php
rename to src/Lang/Ast/Types/ArrayLiteral.php
index 93d4748..b97b387 100644
--- a/src/Ast/Types/ArrayLiteral.php
+++ b/src/Lang/Ast/Types/ArrayLiteral.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Types;
+namespace MonkeyLang\Lang\Ast\Types;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 use function count;
 
diff --git a/src/Ast/Types/BooleanLiteral.php b/src/Lang/Ast/Types/BooleanLiteral.php
similarity index 71%
rename from src/Ast/Types/BooleanLiteral.php
rename to src/Lang/Ast/Types/BooleanLiteral.php
index 9e2aed2..4e77229 100644
--- a/src/Ast/Types/BooleanLiteral.php
+++ b/src/Lang/Ast/Types/BooleanLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Types;
+namespace MonkeyLang\Lang\Ast\Types;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Token\Token;
 
 final class BooleanLiteral extends Expression
 {
diff --git a/src/Ast/Types/FloatLiteral.php b/src/Lang/Ast/Types/FloatLiteral.php
similarity index 71%
rename from src/Ast/Types/FloatLiteral.php
rename to src/Lang/Ast/Types/FloatLiteral.php
index 31102ae..f65bd1b 100644
--- a/src/Ast/Types/FloatLiteral.php
+++ b/src/Lang/Ast/Types/FloatLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Types;
+namespace MonkeyLang\Lang\Ast\Types;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Token\Token;
 
 final class FloatLiteral extends Expression
 {
diff --git a/src/Ast/Types/FunctionLiteral.php b/src/Lang/Ast/Types/FunctionLiteral.php
similarity index 74%
rename from src/Ast/Types/FunctionLiteral.php
rename to src/Lang/Ast/Types/FunctionLiteral.php
index 184f1a6..032a458 100644
--- a/src/Ast/Types/FunctionLiteral.php
+++ b/src/Lang/Ast/Types/FunctionLiteral.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Types;
+namespace MonkeyLang\Lang\Ast\Types;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Support\StringBuilder;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Support\StringBuilder;
+use MonkeyLang\Lang\Token\Token;
 
 use function count;
 
diff --git a/src/Ast/Types/IntegerLiteral.php b/src/Lang/Ast/Types/IntegerLiteral.php
similarity index 71%
rename from src/Ast/Types/IntegerLiteral.php
rename to src/Lang/Ast/Types/IntegerLiteral.php
index ef4e84e..1b641d1 100644
--- a/src/Ast/Types/IntegerLiteral.php
+++ b/src/Lang/Ast/Types/IntegerLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Types;
+namespace MonkeyLang\Lang\Ast\Types;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Token\Token;
 
 final class IntegerLiteral extends Expression
 {
diff --git a/src/Ast/Types/StringLiteral.php b/src/Lang/Ast/Types/StringLiteral.php
similarity index 71%
rename from src/Ast/Types/StringLiteral.php
rename to src/Lang/Ast/Types/StringLiteral.php
index 825c533..5ef4179 100644
--- a/src/Ast/Types/StringLiteral.php
+++ b/src/Lang/Ast/Types/StringLiteral.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Ast\Types;
+namespace MonkeyLang\Lang\Ast\Types;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Token\Token;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Token\Token;
 
 final class StringLiteral extends Expression
 {
diff --git a/src/Evaluator/Builtin/EvalBuiltinFunction.php b/src/Lang/Evaluator/Builtin/EvalBuiltinFunction.php
similarity index 66%
rename from src/Evaluator/Builtin/EvalBuiltinFunction.php
rename to src/Lang/Evaluator/Builtin/EvalBuiltinFunction.php
index ebfab33..347ca37 100644
--- a/src/Evaluator/Builtin/EvalBuiltinFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalBuiltinFunction.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Evaluator\Evaluator;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Evaluator\Evaluator;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 abstract readonly class EvalBuiltinFunction
 {
diff --git a/src/Evaluator/Builtin/EvalFirstFunction.php b/src/Lang/Evaluator/Builtin/EvalFirstFunction.php
similarity index 76%
rename from src/Evaluator/Builtin/EvalFirstFunction.php
rename to src/Lang/Evaluator/Builtin/EvalFirstFunction.php
index 0359df3..2e3ec76 100644
--- a/src/Evaluator/Builtin/EvalFirstFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalFirstFunction.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalLastFunction.php b/src/Lang/Evaluator/Builtin/EvalLastFunction.php
similarity index 76%
rename from src/Evaluator/Builtin/EvalLastFunction.php
rename to src/Lang/Evaluator/Builtin/EvalLastFunction.php
index 208b1f5..6468a65 100644
--- a/src/Evaluator/Builtin/EvalLastFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalLastFunction.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalLenFunction.php b/src/Lang/Evaluator/Builtin/EvalLenFunction.php
similarity index 73%
rename from src/Evaluator/Builtin/EvalLenFunction.php
rename to src/Lang/Evaluator/Builtin/EvalLenFunction.php
index b506833..b730fd1 100644
--- a/src/Evaluator/Builtin/EvalLenFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalLenFunction.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\StringObject;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\StringObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalMapFunction.php b/src/Lang/Evaluator/Builtin/EvalMapFunction.php
similarity index 83%
rename from src/Evaluator/Builtin/EvalMapFunction.php
rename to src/Lang/Evaluator/Builtin/EvalMapFunction.php
index 24241e2..1e587ee 100644
--- a/src/Evaluator/Builtin/EvalMapFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalMapFunction.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\FunctionObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\FunctionObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalPushFunction.php b/src/Lang/Evaluator/Builtin/EvalPushFunction.php
similarity index 79%
rename from src/Evaluator/Builtin/EvalPushFunction.php
rename to src/Lang/Evaluator/Builtin/EvalPushFunction.php
index 7d38c1a..27d6f13 100644
--- a/src/Evaluator/Builtin/EvalPushFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalPushFunction.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalPutsFunction.php b/src/Lang/Evaluator/Builtin/EvalPutsFunction.php
similarity index 75%
rename from src/Evaluator/Builtin/EvalPutsFunction.php
rename to src/Lang/Evaluator/Builtin/EvalPutsFunction.php
index b2580e0..6c146b5 100644
--- a/src/Evaluator/Builtin/EvalPutsFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalPutsFunction.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
 
 use function count;
 
diff --git a/src/Evaluator/Builtin/EvalSliceFunction.php b/src/Lang/Evaluator/Builtin/EvalSliceFunction.php
similarity index 86%
rename from src/Evaluator/Builtin/EvalSliceFunction.php
rename to src/Lang/Evaluator/Builtin/EvalSliceFunction.php
index 58dac80..5560beb 100644
--- a/src/Evaluator/Builtin/EvalSliceFunction.php
+++ b/src/Lang/Evaluator/Builtin/EvalSliceFunction.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator\Builtin;
+namespace MonkeyLang\Lang\Evaluator\Builtin;
 
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\StringObject;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\StringObject;
 
 use function array_slice;
 use function count;
diff --git a/src/Evaluator/BuiltinFunction.php b/src/Lang/Evaluator/BuiltinFunction.php
similarity index 77%
rename from src/Evaluator/BuiltinFunction.php
rename to src/Lang/Evaluator/BuiltinFunction.php
index 40abace..2ccd4e3 100644
--- a/src/Evaluator/BuiltinFunction.php
+++ b/src/Lang/Evaluator/BuiltinFunction.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
 use Closure;
-use MonkeyLang\Object\BuiltinFunctionObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\BuiltinFunctionObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final class BuiltinFunction
 {
diff --git a/src/Evaluator/Environment.php b/src/Lang/Evaluator/Environment.php
similarity index 85%
rename from src/Evaluator/Environment.php
rename to src/Lang/Evaluator/Environment.php
index 8397798..bb8dfb8 100644
--- a/src/Evaluator/Environment.php
+++ b/src/Lang/Evaluator/Environment.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final class Environment
 {
diff --git a/src/Evaluator/EvalArrayBinaryExpression.php b/src/Lang/Evaluator/EvalArrayBinaryExpression.php
similarity index 74%
rename from src/Evaluator/EvalArrayBinaryExpression.php
rename to src/Lang/Evaluator/EvalArrayBinaryExpression.php
index 9e092ba..2bb0cff 100644
--- a/src/Evaluator/EvalArrayBinaryExpression.php
+++ b/src/Lang/Evaluator/EvalArrayBinaryExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final class EvalArrayBinaryExpression
 {
diff --git a/src/Evaluator/EvalArrayLiteral.php b/src/Lang/Evaluator/EvalArrayLiteral.php
similarity index 73%
rename from src/Evaluator/EvalArrayLiteral.php
rename to src/Lang/Evaluator/EvalArrayLiteral.php
index da1db64..d7eb8e1 100644
--- a/src/Evaluator/EvalArrayLiteral.php
+++ b/src/Lang/Evaluator/EvalArrayLiteral.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Types\ArrayLiteral;
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 use function count;
 
diff --git a/src/Evaluator/EvalAssingStatement.php b/src/Lang/Evaluator/EvalAssingStatement.php
similarity index 82%
rename from src/Evaluator/EvalAssingStatement.php
rename to src/Lang/Evaluator/EvalAssingStatement.php
index 9677758..6b8a089 100644
--- a/src/Evaluator/EvalAssingStatement.php
+++ b/src/Lang/Evaluator/EvalAssingStatement.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Statements\AssignStatement;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Ast\Statements\AssignStatement;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final readonly class EvalAssingStatement
 {
diff --git a/src/Evaluator/EvalBinaryExpression.php b/src/Lang/Evaluator/EvalBinaryExpression.php
similarity index 83%
rename from src/Evaluator/EvalBinaryExpression.php
rename to src/Lang/Evaluator/EvalBinaryExpression.php
index 29a251c..335f870 100644
--- a/src/Evaluator/EvalBinaryExpression.php
+++ b/src/Lang/Evaluator/EvalBinaryExpression.php
@@ -2,15 +2,15 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
-
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\BooleanObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\FloatObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\StringObject;
+namespace MonkeyLang\Lang\Evaluator;
+
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\BooleanObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\FloatObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\StringObject;
 
 final class EvalBinaryExpression
 {
diff --git a/src/Evaluator/EvalBlockStatement.php b/src/Lang/Evaluator/EvalBlockStatement.php
similarity index 73%
rename from src/Evaluator/EvalBlockStatement.php
rename to src/Lang/Evaluator/EvalBlockStatement.php
index 2bc4b0d..8fc14fc 100644
--- a/src/Evaluator/EvalBlockStatement.php
+++ b/src/Lang/Evaluator/EvalBlockStatement.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
-use MonkeyLang\Object\ReturnValueObject;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
+use MonkeyLang\Lang\Object\ReturnValueObject;
 
 final readonly class EvalBlockStatement
 {
diff --git a/src/Evaluator/EvalCallExpression.php b/src/Lang/Evaluator/EvalCallExpression.php
similarity index 87%
rename from src/Evaluator/EvalCallExpression.php
rename to src/Lang/Evaluator/EvalCallExpression.php
index 53e5f8c..9d154a5 100644
--- a/src/Evaluator/EvalCallExpression.php
+++ b/src/Lang/Evaluator/EvalCallExpression.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
-
-use MonkeyLang\Ast\Expressions\CallExpression;
-use MonkeyLang\Object\BuiltinFunctionObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\FunctionObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\ReturnValueObject;
+namespace MonkeyLang\Lang\Evaluator;
+
+use MonkeyLang\Lang\Ast\Expressions\CallExpression;
+use MonkeyLang\Lang\Object\BuiltinFunctionObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\FunctionObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\ReturnValueObject;
 
 use function call_user_func;
 use function count;
diff --git a/src/Evaluator/EvalIdentifier.php b/src/Lang/Evaluator/EvalIdentifier.php
similarity index 75%
rename from src/Evaluator/EvalIdentifier.php
rename to src/Lang/Evaluator/EvalIdentifier.php
index 080d4b0..d9a8340 100644
--- a/src/Evaluator/EvalIdentifier.php
+++ b/src/Lang/Evaluator/EvalIdentifier.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final readonly class EvalIdentifier
 {
diff --git a/src/Evaluator/EvalIfExpression.php b/src/Lang/Evaluator/EvalIfExpression.php
similarity index 76%
rename from src/Evaluator/EvalIfExpression.php
rename to src/Lang/Evaluator/EvalIfExpression.php
index 370ddb2..b56a52e 100644
--- a/src/Evaluator/EvalIfExpression.php
+++ b/src/Lang/Evaluator/EvalIfExpression.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Expressions\IfExpression;
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
+use MonkeyLang\Lang\Ast\Expressions\IfExpression;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
 
 final readonly class EvalIfExpression
 {
diff --git a/src/Evaluator/EvalIndexExpression.php b/src/Lang/Evaluator/EvalIndexExpression.php
similarity index 75%
rename from src/Evaluator/EvalIndexExpression.php
rename to src/Lang/Evaluator/EvalIndexExpression.php
index 402236a..5840129 100644
--- a/src/Evaluator/EvalIndexExpression.php
+++ b/src/Lang/Evaluator/EvalIndexExpression.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
-
-use MonkeyLang\Ast\Expressions\IndexExpression;
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
+namespace MonkeyLang\Lang\Evaluator;
+
+use MonkeyLang\Lang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
 
 final readonly class EvalIndexExpression
 {
diff --git a/src/Evaluator/EvalLetStatement.php b/src/Lang/Evaluator/EvalLetStatement.php
similarity index 79%
rename from src/Evaluator/EvalLetStatement.php
rename to src/Lang/Evaluator/EvalLetStatement.php
index 7437fec..c3f3aa1 100644
--- a/src/Evaluator/EvalLetStatement.php
+++ b/src/Lang/Evaluator/EvalLetStatement.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Statements\LetStatement;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Ast\Statements\LetStatement;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final readonly class EvalLetStatement
 {
diff --git a/src/Evaluator/EvalMinusUnaryOperatorExpression.php b/src/Lang/Evaluator/EvalMinusUnaryOperatorExpression.php
similarity index 70%
rename from src/Evaluator/EvalMinusUnaryOperatorExpression.php
rename to src/Lang/Evaluator/EvalMinusUnaryOperatorExpression.php
index 2abb607..47418f5 100644
--- a/src/Evaluator/EvalMinusUnaryOperatorExpression.php
+++ b/src/Lang/Evaluator/EvalMinusUnaryOperatorExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final class EvalMinusUnaryOperatorExpression
 {
diff --git a/src/Evaluator/EvalNotOperatorExpression.php b/src/Lang/Evaluator/EvalNotOperatorExpression.php
similarity index 72%
rename from src/Evaluator/EvalNotOperatorExpression.php
rename to src/Lang/Evaluator/EvalNotOperatorExpression.php
index 46743b8..8f33739 100644
--- a/src/Evaluator/EvalNotOperatorExpression.php
+++ b/src/Lang/Evaluator/EvalNotOperatorExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Object\BooleanObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
+use MonkeyLang\Lang\Object\BooleanObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
 
 final class EvalNotOperatorExpression
 {
diff --git a/src/Evaluator/EvalNumericBinaryExpression.php b/src/Lang/Evaluator/EvalNumericBinaryExpression.php
similarity index 88%
rename from src/Evaluator/EvalNumericBinaryExpression.php
rename to src/Lang/Evaluator/EvalNumericBinaryExpression.php
index 5b53000..89ce950 100644
--- a/src/Evaluator/EvalNumericBinaryExpression.php
+++ b/src/Lang/Evaluator/EvalNumericBinaryExpression.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Object\BooleanObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\BooleanObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final class EvalNumericBinaryExpression
 {
diff --git a/src/Evaluator/EvalPostfixExpression.php b/src/Lang/Evaluator/EvalPostfixExpression.php
similarity index 86%
rename from src/Evaluator/EvalPostfixExpression.php
rename to src/Lang/Evaluator/EvalPostfixExpression.php
index f022174..bf674a2 100644
--- a/src/Evaluator/EvalPostfixExpression.php
+++ b/src/Lang/Evaluator/EvalPostfixExpression.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Expressions\PostfixExpression;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final readonly class EvalPostfixExpression
 {
diff --git a/src/Evaluator/EvalProgram.php b/src/Lang/Evaluator/EvalProgram.php
similarity index 74%
rename from src/Evaluator/EvalProgram.php
rename to src/Lang/Evaluator/EvalProgram.php
index b1d4854..ecf1b60 100644
--- a/src/Evaluator/EvalProgram.php
+++ b/src/Lang/Evaluator/EvalProgram.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Program;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
-use MonkeyLang\Object\ReturnValueObject;
+use MonkeyLang\Lang\Ast\Program;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
+use MonkeyLang\Lang\Object\ReturnValueObject;
 
 final readonly class EvalProgram
 {
diff --git a/src/Evaluator/EvalReturnStatement.php b/src/Lang/Evaluator/EvalReturnStatement.php
similarity index 71%
rename from src/Evaluator/EvalReturnStatement.php
rename to src/Lang/Evaluator/EvalReturnStatement.php
index 75fd6f3..a56b22a 100644
--- a/src/Evaluator/EvalReturnStatement.php
+++ b/src/Lang/Evaluator/EvalReturnStatement.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Statements\ReturnStatement;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\ReturnValueObject;
+use MonkeyLang\Lang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\ReturnValueObject;
 
 final readonly class EvalReturnStatement
 {
diff --git a/src/Evaluator/EvalStringBinaryExpression.php b/src/Lang/Evaluator/EvalStringBinaryExpression.php
similarity index 74%
rename from src/Evaluator/EvalStringBinaryExpression.php
rename to src/Lang/Evaluator/EvalStringBinaryExpression.php
index a667893..08a90ad 100644
--- a/src/Evaluator/EvalStringBinaryExpression.php
+++ b/src/Lang/Evaluator/EvalStringBinaryExpression.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Object\BooleanObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\StringObject;
+use MonkeyLang\Lang\Object\BooleanObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\StringObject;
 
 final class EvalStringBinaryExpression
 {
diff --git a/src/Evaluator/EvalUnaryExpression.php b/src/Lang/Evaluator/EvalUnaryExpression.php
similarity index 82%
rename from src/Evaluator/EvalUnaryExpression.php
rename to src/Lang/Evaluator/EvalUnaryExpression.php
index 5a01ce9..b29b2ae 100644
--- a/src/Evaluator/EvalUnaryExpression.php
+++ b/src/Lang/Evaluator/EvalUnaryExpression.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final class EvalUnaryExpression
 {
diff --git a/src/Evaluator/EvalWhileExpression.php b/src/Lang/Evaluator/EvalWhileExpression.php
similarity index 80%
rename from src/Evaluator/EvalWhileExpression.php
rename to src/Lang/Evaluator/EvalWhileExpression.php
index 0042895..c6dc650 100644
--- a/src/Evaluator/EvalWhileExpression.php
+++ b/src/Lang/Evaluator/EvalWhileExpression.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Expressions\WhileExpression;
-use MonkeyLang\Object\BooleanObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\MonkeyObject;
+use MonkeyLang\Lang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Lang\Object\BooleanObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
 
 final readonly class EvalWhileExpression
 {
diff --git a/src/Evaluator/Evaluator.php b/src/Lang/Evaluator/Evaluator.php
similarity index 66%
rename from src/Evaluator/Evaluator.php
rename to src/Lang/Evaluator/Evaluator.php
index 0f72e55..40a6bf3 100644
--- a/src/Evaluator/Evaluator.php
+++ b/src/Lang/Evaluator/Evaluator.php
@@ -2,45 +2,45 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Evaluator;
+namespace MonkeyLang\Lang\Evaluator;
 
-use MonkeyLang\Ast\Expressions\BinaryExpression;
-use MonkeyLang\Ast\Expressions\CallExpression;
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Ast\Expressions\IfExpression;
-use MonkeyLang\Ast\Expressions\IndexExpression;
-use MonkeyLang\Ast\Expressions\PostfixExpression;
-use MonkeyLang\Ast\Expressions\UnaryExpression;
-use MonkeyLang\Ast\Expressions\WhileExpression;
-use MonkeyLang\Ast\Node;
-use MonkeyLang\Ast\Program;
-use MonkeyLang\Ast\Statements\AssignStatement;
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Ast\Statements\ExpressionStatement;
-use MonkeyLang\Ast\Statements\LetStatement;
-use MonkeyLang\Ast\Statements\ReturnStatement;
-use MonkeyLang\Ast\Types\ArrayLiteral;
-use MonkeyLang\Ast\Types\BooleanLiteral;
-use MonkeyLang\Ast\Types\FloatLiteral;
-use MonkeyLang\Ast\Types\FunctionLiteral;
-use MonkeyLang\Ast\Types\IntegerLiteral;
-use MonkeyLang\Ast\Types\StringLiteral;
-use MonkeyLang\Evaluator\Builtin\EvalFirstFunction;
-use MonkeyLang\Evaluator\Builtin\EvalLastFunction;
-use MonkeyLang\Evaluator\Builtin\EvalLenFunction;
-use MonkeyLang\Evaluator\Builtin\EvalMapFunction;
-use MonkeyLang\Evaluator\Builtin\EvalPushFunction;
-use MonkeyLang\Evaluator\Builtin\EvalPutsFunction;
-use MonkeyLang\Evaluator\Builtin\EvalSliceFunction;
-use MonkeyLang\Object\BooleanObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\FloatObject;
-use MonkeyLang\Object\FunctionObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
-use MonkeyLang\Object\StringObject;
+use MonkeyLang\Lang\Ast\Expressions\BinaryExpression;
+use MonkeyLang\Lang\Ast\Expressions\CallExpression;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Ast\Expressions\IfExpression;
+use MonkeyLang\Lang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Lang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Lang\Ast\Expressions\UnaryExpression;
+use MonkeyLang\Lang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Lang\Ast\Node;
+use MonkeyLang\Lang\Ast\Program;
+use MonkeyLang\Lang\Ast\Statements\AssignStatement;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Ast\Statements\ExpressionStatement;
+use MonkeyLang\Lang\Ast\Statements\LetStatement;
+use MonkeyLang\Lang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Lang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Lang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Lang\Ast\Types\FloatLiteral;
+use MonkeyLang\Lang\Ast\Types\FunctionLiteral;
+use MonkeyLang\Lang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Lang\Ast\Types\StringLiteral;
+use MonkeyLang\Lang\Evaluator\Builtin\EvalFirstFunction;
+use MonkeyLang\Lang\Evaluator\Builtin\EvalLastFunction;
+use MonkeyLang\Lang\Evaluator\Builtin\EvalLenFunction;
+use MonkeyLang\Lang\Evaluator\Builtin\EvalMapFunction;
+use MonkeyLang\Lang\Evaluator\Builtin\EvalPushFunction;
+use MonkeyLang\Lang\Evaluator\Builtin\EvalPutsFunction;
+use MonkeyLang\Lang\Evaluator\Builtin\EvalSliceFunction;
+use MonkeyLang\Lang\Object\BooleanObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\FloatObject;
+use MonkeyLang\Lang\Object\FunctionObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
+use MonkeyLang\Lang\Object\StringObject;
 
 use function call_user_func;
 
diff --git a/src/Lexer/Char.php b/src/Lang/Lexer/Char.php
similarity index 97%
rename from src/Lexer/Char.php
rename to src/Lang/Lexer/Char.php
index 3022b87..39c4b90 100644
--- a/src/Lexer/Char.php
+++ b/src/Lang/Lexer/Char.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Lexer;
+namespace MonkeyLang\Lang\Lexer;
 
 use Stringable;
 
diff --git a/src/Lexer/Input.php b/src/Lang/Lexer/Input.php
similarity index 94%
rename from src/Lexer/Input.php
rename to src/Lang/Lexer/Input.php
index a9a6d37..0fc3e46 100644
--- a/src/Lexer/Input.php
+++ b/src/Lang/Lexer/Input.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Lexer;
+namespace MonkeyLang\Lang\Lexer;
 
 final class Input
 {
diff --git a/src/Lexer/Lexer.php b/src/Lang/Lexer/Lexer.php
similarity index 97%
rename from src/Lexer/Lexer.php
rename to src/Lang/Lexer/Lexer.php
index 57ba799..11ae09c 100644
--- a/src/Lexer/Lexer.php
+++ b/src/Lang/Lexer/Lexer.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Lexer;
+namespace MonkeyLang\Lang\Lexer;
 
-use MonkeyLang\Token\Token;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Token\Token;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class Lexer
 {
diff --git a/src/Object/ArrayObject.php b/src/Lang/Object/ArrayObject.php
similarity index 96%
rename from src/Object/ArrayObject.php
rename to src/Lang/Object/ArrayObject.php
index 2f5cac3..3728cae 100644
--- a/src/Object/ArrayObject.php
+++ b/src/Lang/Object/ArrayObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 use function count;
 use function sprintf;
diff --git a/src/Object/BooleanObject.php b/src/Lang/Object/BooleanObject.php
similarity index 95%
rename from src/Object/BooleanObject.php
rename to src/Lang/Object/BooleanObject.php
index 79a9382..502aab6 100644
--- a/src/Object/BooleanObject.php
+++ b/src/Lang/Object/BooleanObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 final readonly class BooleanObject extends MonkeyObject
 {
diff --git a/src/Object/BuiltinFunctionObject.php b/src/Lang/Object/BuiltinFunctionObject.php
similarity index 93%
rename from src/Object/BuiltinFunctionObject.php
rename to src/Lang/Object/BuiltinFunctionObject.php
index 6d2708c..8e80f23 100644
--- a/src/Object/BuiltinFunctionObject.php
+++ b/src/Lang/Object/BuiltinFunctionObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 use Closure;
 
diff --git a/src/Object/ErrorObject.php b/src/Lang/Object/ErrorObject.php
similarity index 97%
rename from src/Object/ErrorObject.php
rename to src/Lang/Object/ErrorObject.php
index 7331a56..413a4ac 100644
--- a/src/Object/ErrorObject.php
+++ b/src/Lang/Object/ErrorObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 use function sprintf;
 
diff --git a/src/Object/FloatObject.php b/src/Lang/Object/FloatObject.php
similarity index 93%
rename from src/Object/FloatObject.php
rename to src/Lang/Object/FloatObject.php
index 206bbcd..b594a91 100644
--- a/src/Object/FloatObject.php
+++ b/src/Lang/Object/FloatObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 use function sprintf;
 
diff --git a/src/Object/FunctionObject.php b/src/Lang/Object/FunctionObject.php
similarity index 83%
rename from src/Object/FunctionObject.php
rename to src/Lang/Object/FunctionObject.php
index 6aba678..3b1b561 100644
--- a/src/Object/FunctionObject.php
+++ b/src/Lang/Object/FunctionObject.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Evaluator\Environment;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Evaluator\Environment;
 
 use function sprintf;
 
diff --git a/src/Object/IntegerObject.php b/src/Lang/Object/IntegerObject.php
similarity index 93%
rename from src/Object/IntegerObject.php
rename to src/Lang/Object/IntegerObject.php
index 59dbbfa..608f90b 100644
--- a/src/Object/IntegerObject.php
+++ b/src/Lang/Object/IntegerObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 use function sprintf;
 
diff --git a/src/Object/MonkeyObject.php b/src/Lang/Object/MonkeyObject.php
similarity index 95%
rename from src/Object/MonkeyObject.php
rename to src/Lang/Object/MonkeyObject.php
index 1c1954f..0abd0b2 100644
--- a/src/Object/MonkeyObject.php
+++ b/src/Lang/Object/MonkeyObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 abstract readonly class MonkeyObject
 {
diff --git a/src/Object/MonkeyObjectType.php b/src/Lang/Object/MonkeyObjectType.php
similarity index 96%
rename from src/Object/MonkeyObjectType.php
rename to src/Lang/Object/MonkeyObjectType.php
index 867388d..cbadf2e 100644
--- a/src/Object/MonkeyObjectType.php
+++ b/src/Lang/Object/MonkeyObjectType.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 enum MonkeyObjectType: int
 {
diff --git a/src/Object/NullObject.php b/src/Lang/Object/NullObject.php
similarity index 93%
rename from src/Object/NullObject.php
rename to src/Lang/Object/NullObject.php
index fbec8f3..f9d91ee 100644
--- a/src/Object/NullObject.php
+++ b/src/Lang/Object/NullObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 final readonly class NullObject extends MonkeyObject
 {
diff --git a/src/Object/ReturnValueObject.php b/src/Lang/Object/ReturnValueObject.php
similarity index 93%
rename from src/Object/ReturnValueObject.php
rename to src/Lang/Object/ReturnValueObject.php
index fa631f1..2f37c5f 100644
--- a/src/Object/ReturnValueObject.php
+++ b/src/Lang/Object/ReturnValueObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 final readonly class ReturnValueObject extends MonkeyObject
 {
diff --git a/src/Object/StringObject.php b/src/Lang/Object/StringObject.php
similarity index 94%
rename from src/Object/StringObject.php
rename to src/Lang/Object/StringObject.php
index 9ebafa3..ba6ffed 100644
--- a/src/Object/StringObject.php
+++ b/src/Lang/Object/StringObject.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Object;
+namespace MonkeyLang\Lang\Object;
 
 final readonly class StringObject extends MonkeyObject
 {
diff --git a/src/Parser/ExpressionListParser.php b/src/Lang/Parser/ExpressionListParser.php
similarity index 86%
rename from src/Parser/ExpressionListParser.php
rename to src/Lang/Parser/ExpressionListParser.php
index 730fd94..ff1b94c 100644
--- a/src/Parser/ExpressionListParser.php
+++ b/src/Lang/Parser/ExpressionListParser.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser;
+namespace MonkeyLang\Lang\Parser;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class ExpressionListParser
 {
diff --git a/src/Parser/FunctionParametersParser.php b/src/Lang/Parser/FunctionParametersParser.php
similarity index 87%
rename from src/Parser/FunctionParametersParser.php
rename to src/Lang/Parser/FunctionParametersParser.php
index a56783a..ab84438 100644
--- a/src/Parser/FunctionParametersParser.php
+++ b/src/Lang/Parser/FunctionParametersParser.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser;
+namespace MonkeyLang\Lang\Parser;
 
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class FunctionParametersParser
 {
diff --git a/src/Parser/Parselet/ArrayParselet.php b/src/Lang/Parser/Parselet/ArrayParselet.php
similarity index 61%
rename from src/Parser/Parselet/ArrayParselet.php
rename to src/Lang/Parser/Parselet/ArrayParselet.php
index 8e5b851..de3bdde 100644
--- a/src/Parser/Parselet/ArrayParselet.php
+++ b/src/Lang/Parser/Parselet/ArrayParselet.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Types\ArrayLiteral;
-use MonkeyLang\Parser\ExpressionListParser;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Lang\Parser\ExpressionListParser;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final readonly class ArrayParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/BinaryOperatorParselet.php b/src/Lang/Parser/Parselet/BinaryOperatorParselet.php
similarity index 75%
rename from src/Parser/Parselet/BinaryOperatorParselet.php
rename to src/Lang/Parser/Parselet/BinaryOperatorParselet.php
index 2436183..f79a464 100644
--- a/src/Parser/Parselet/BinaryOperatorParselet.php
+++ b/src/Lang/Parser/Parselet/BinaryOperatorParselet.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\BinaryExpression;
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Parser\Parser;
+use MonkeyLang\Lang\Ast\Expressions\BinaryExpression;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Parser\Parser;
 
 final readonly class BinaryOperatorParselet implements InfixParselet
 {
diff --git a/src/Parser/Parselet/CallExpressionParselet.php b/src/Lang/Parser/Parselet/CallExpressionParselet.php
similarity index 63%
rename from src/Parser/Parselet/CallExpressionParselet.php
rename to src/Lang/Parser/Parselet/CallExpressionParselet.php
index 62469a0..f7db74c 100644
--- a/src/Parser/Parselet/CallExpressionParselet.php
+++ b/src/Lang/Parser/Parselet/CallExpressionParselet.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\CallExpression;
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Parser\ExpressionListParser;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\CallExpression;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Parser\ExpressionListParser;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final readonly class CallExpressionParselet implements InfixParselet
 {
diff --git a/src/Parser/Parselet/FunctionLiteralParselet.php b/src/Lang/Parser/Parselet/FunctionLiteralParselet.php
similarity index 67%
rename from src/Parser/Parselet/FunctionLiteralParselet.php
rename to src/Lang/Parser/Parselet/FunctionLiteralParselet.php
index 5b1e734..113c24c 100644
--- a/src/Parser/Parselet/FunctionLiteralParselet.php
+++ b/src/Lang/Parser/Parselet/FunctionLiteralParselet.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
-
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Types\FunctionLiteral;
-use MonkeyLang\Parser\FunctionParametersParser;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Statements\BlockStatementParser;
-use MonkeyLang\Token\TokenType;
+namespace MonkeyLang\Lang\Parser\Parselet;
+
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Types\FunctionLiteral;
+use MonkeyLang\Lang\Parser\FunctionParametersParser;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Statements\BlockStatementParser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final readonly class FunctionLiteralParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/GroupedExpressionParselet.php b/src/Lang/Parser/Parselet/GroupedExpressionParselet.php
similarity index 72%
rename from src/Parser/Parselet/GroupedExpressionParselet.php
rename to src/Lang/Parser/Parselet/GroupedExpressionParselet.php
index 0a7e0bf..4743aef 100644
--- a/src/Parser/Parselet/GroupedExpressionParselet.php
+++ b/src/Lang/Parser/Parselet/GroupedExpressionParselet.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Token\TokenType;
 
 final readonly class GroupedExpressionParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/IdentifierParselet.php b/src/Lang/Parser/Parselet/IdentifierParselet.php
similarity index 65%
rename from src/Parser/Parselet/IdentifierParselet.php
rename to src/Lang/Parser/Parselet/IdentifierParselet.php
index 101562d..31466e8 100644
--- a/src/Parser/Parselet/IdentifierParselet.php
+++ b/src/Lang/Parser/Parselet/IdentifierParselet.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Parser\Parser;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Parser\Parser;
 
 final readonly class IdentifierParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/IfExpressionParselet.php b/src/Lang/Parser/Parselet/IfExpressionParselet.php
similarity index 79%
rename from src/Parser/Parselet/IfExpressionParselet.php
rename to src/Lang/Parser/Parselet/IfExpressionParselet.php
index 3210176..ed787aa 100644
--- a/src/Parser/Parselet/IfExpressionParselet.php
+++ b/src/Lang/Parser/Parselet/IfExpressionParselet.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
-
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IfExpression;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Parser\Statements\BlockStatementParser;
-use MonkeyLang\Token\TokenType;
+namespace MonkeyLang\Lang\Parser\Parselet;
+
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IfExpression;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Parser\Statements\BlockStatementParser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final readonly class IfExpressionParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/IndexExpressionParselet.php b/src/Lang/Parser/Parselet/IndexExpressionParselet.php
similarity index 72%
rename from src/Parser/Parselet/IndexExpressionParselet.php
rename to src/Lang/Parser/Parselet/IndexExpressionParselet.php
index 70e544c..acd2ed2 100644
--- a/src/Parser/Parselet/IndexExpressionParselet.php
+++ b/src/Lang/Parser/Parselet/IndexExpressionParselet.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IndexExpression;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Token\TokenType;
 
 final readonly class IndexExpressionParselet implements InfixParselet
 {
diff --git a/src/Parser/Parselet/InfixParselet.php b/src/Lang/Parser/Parselet/InfixParselet.php
similarity index 58%
rename from src/Parser/Parselet/InfixParselet.php
rename to src/Lang/Parser/Parselet/InfixParselet.php
index ed723a6..89f986c 100644
--- a/src/Parser/Parselet/InfixParselet.php
+++ b/src/Lang/Parser/Parselet/InfixParselet.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
 
 interface InfixParselet
 {
diff --git a/src/Parser/Parselet/PostfixOperatorParselet.php b/src/Lang/Parser/Parselet/PostfixOperatorParselet.php
similarity index 65%
rename from src/Parser/Parselet/PostfixOperatorParselet.php
rename to src/Lang/Parser/Parselet/PostfixOperatorParselet.php
index 4a900ca..0aa796e 100644
--- a/src/Parser/Parselet/PostfixOperatorParselet.php
+++ b/src/Lang/Parser/Parselet/PostfixOperatorParselet.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\PostfixExpression;
-use MonkeyLang\Parser\Parser;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Lang\Parser\Parser;
 
 final readonly class PostfixOperatorParselet implements PostfixParselet
 {
diff --git a/src/Parser/Parselet/PostfixParselet.php b/src/Lang/Parser/Parselet/PostfixParselet.php
similarity index 53%
rename from src/Parser/Parselet/PostfixParselet.php
rename to src/Lang/Parser/Parselet/PostfixParselet.php
index 151830c..4fe251e 100644
--- a/src/Parser/Parselet/PostfixParselet.php
+++ b/src/Lang/Parser/Parselet/PostfixParselet.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
 
 interface PostfixParselet
 {
diff --git a/src/Parser/Parselet/PrefixParselet.php b/src/Lang/Parser/Parselet/PrefixParselet.php
similarity index 53%
rename from src/Parser/Parselet/PrefixParselet.php
rename to src/Lang/Parser/Parselet/PrefixParselet.php
index 66c661a..f5bad8d 100644
--- a/src/Parser/Parselet/PrefixParselet.php
+++ b/src/Lang/Parser/Parselet/PrefixParselet.php
@@ -2,9 +2,9 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
 
 interface PrefixParselet
 {
diff --git a/src/Parser/Parselet/ScalarParselet.php b/src/Lang/Parser/Parselet/ScalarParselet.php
similarity index 70%
rename from src/Parser/Parselet/ScalarParselet.php
rename to src/Lang/Parser/Parselet/ScalarParselet.php
index 4a12258..389fa0f 100644
--- a/src/Parser/Parselet/ScalarParselet.php
+++ b/src/Lang/Parser/Parselet/ScalarParselet.php
@@ -2,16 +2,16 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
 use InvalidArgumentException;
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Types\BooleanLiteral;
-use MonkeyLang\Ast\Types\FloatLiteral;
-use MonkeyLang\Ast\Types\IntegerLiteral;
-use MonkeyLang\Ast\Types\StringLiteral;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Lang\Ast\Types\FloatLiteral;
+use MonkeyLang\Lang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Lang\Ast\Types\StringLiteral;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class ScalarParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/UnaryOperatorParselet.php b/src/Lang/Parser/Parselet/UnaryOperatorParselet.php
similarity index 69%
rename from src/Parser/Parselet/UnaryOperatorParselet.php
rename to src/Lang/Parser/Parselet/UnaryOperatorParselet.php
index ed69bc8..795d9f7 100644
--- a/src/Parser/Parselet/UnaryOperatorParselet.php
+++ b/src/Lang/Parser/Parselet/UnaryOperatorParselet.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
+namespace MonkeyLang\Lang\Parser\Parselet;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\UnaryExpression;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\UnaryExpression;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
 
 final readonly class UnaryOperatorParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parselet/WhileExpressionParselet.php b/src/Lang/Parser/Parselet/WhileExpressionParselet.php
similarity index 73%
rename from src/Parser/Parselet/WhileExpressionParselet.php
rename to src/Lang/Parser/Parselet/WhileExpressionParselet.php
index f8255f4..012a35b 100644
--- a/src/Parser/Parselet/WhileExpressionParselet.php
+++ b/src/Lang/Parser/Parselet/WhileExpressionParselet.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Parselet;
-
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\WhileExpression;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Parser\Statements\BlockStatementParser;
-use MonkeyLang\Token\TokenType;
+namespace MonkeyLang\Lang\Parser\Parselet;
+
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Parser\Statements\BlockStatementParser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final readonly class WhileExpressionParselet implements PrefixParselet
 {
diff --git a/src/Parser/Parser.php b/src/Lang/Parser/Parser.php
similarity index 85%
rename from src/Parser/Parser.php
rename to src/Lang/Parser/Parser.php
index 76e2173..b928af1 100644
--- a/src/Parser/Parser.php
+++ b/src/Lang/Parser/Parser.php
@@ -2,27 +2,27 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser;
-
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Lexer\Lexer;
-use MonkeyLang\Parser\Parselet\ArrayParselet;
-use MonkeyLang\Parser\Parselet\BinaryOperatorParselet;
-use MonkeyLang\Parser\Parselet\CallExpressionParselet;
-use MonkeyLang\Parser\Parselet\FunctionLiteralParselet;
-use MonkeyLang\Parser\Parselet\GroupedExpressionParselet;
-use MonkeyLang\Parser\Parselet\IdentifierParselet;
-use MonkeyLang\Parser\Parselet\IfExpressionParselet;
-use MonkeyLang\Parser\Parselet\IndexExpressionParselet;
-use MonkeyLang\Parser\Parselet\InfixParselet;
-use MonkeyLang\Parser\Parselet\PostfixOperatorParselet;
-use MonkeyLang\Parser\Parselet\PostfixParselet;
-use MonkeyLang\Parser\Parselet\PrefixParselet;
-use MonkeyLang\Parser\Parselet\ScalarParselet;
-use MonkeyLang\Parser\Parselet\UnaryOperatorParselet;
-use MonkeyLang\Parser\Parselet\WhileExpressionParselet;
-use MonkeyLang\Token\Token;
-use MonkeyLang\Token\TokenType;
+namespace MonkeyLang\Lang\Parser;
+
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Lexer\Lexer;
+use MonkeyLang\Lang\Parser\Parselet\ArrayParselet;
+use MonkeyLang\Lang\Parser\Parselet\BinaryOperatorParselet;
+use MonkeyLang\Lang\Parser\Parselet\CallExpressionParselet;
+use MonkeyLang\Lang\Parser\Parselet\FunctionLiteralParselet;
+use MonkeyLang\Lang\Parser\Parselet\GroupedExpressionParselet;
+use MonkeyLang\Lang\Parser\Parselet\IdentifierParselet;
+use MonkeyLang\Lang\Parser\Parselet\IfExpressionParselet;
+use MonkeyLang\Lang\Parser\Parselet\IndexExpressionParselet;
+use MonkeyLang\Lang\Parser\Parselet\InfixParselet;
+use MonkeyLang\Lang\Parser\Parselet\PostfixOperatorParselet;
+use MonkeyLang\Lang\Parser\Parselet\PostfixParselet;
+use MonkeyLang\Lang\Parser\Parselet\PrefixParselet;
+use MonkeyLang\Lang\Parser\Parselet\ScalarParselet;
+use MonkeyLang\Lang\Parser\Parselet\UnaryOperatorParselet;
+use MonkeyLang\Lang\Parser\Parselet\WhileExpressionParselet;
+use MonkeyLang\Lang\Token\Token;
+use MonkeyLang\Lang\Token\TokenType;
 
 use function sprintf;
 
diff --git a/src/Parser/Precedence.php b/src/Lang/Parser/Precedence.php
similarity index 90%
rename from src/Parser/Precedence.php
rename to src/Lang/Parser/Precedence.php
index 9fd734f..ad8d25e 100644
--- a/src/Parser/Precedence.php
+++ b/src/Lang/Parser/Precedence.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser;
+namespace MonkeyLang\Lang\Parser;
 
 enum Precedence: int
 {
diff --git a/src/Parser/ProgramParser.php b/src/Lang/Parser/ProgramParser.php
similarity index 69%
rename from src/Parser/ProgramParser.php
rename to src/Lang/Parser/ProgramParser.php
index 1e988b8..6cc558c 100644
--- a/src/Parser/ProgramParser.php
+++ b/src/Lang/Parser/ProgramParser.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser;
+namespace MonkeyLang\Lang\Parser;
 
-use MonkeyLang\Ast\Program;
-use MonkeyLang\Ast\Statements\Statement;
-use MonkeyLang\Parser\Statements\StatementParser;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Program;
+use MonkeyLang\Lang\Ast\Statements\Statement;
+use MonkeyLang\Lang\Parser\Statements\StatementParser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class ProgramParser
 {
diff --git a/src/Parser/Statements/AssignStatementParser.php b/src/Lang/Parser/Statements/AssignStatementParser.php
similarity index 66%
rename from src/Parser/Statements/AssignStatementParser.php
rename to src/Lang/Parser/Statements/AssignStatementParser.php
index a51b524..541f849 100644
--- a/src/Parser/Statements/AssignStatementParser.php
+++ b/src/Lang/Parser/Statements/AssignStatementParser.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Statements;
-
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Ast\Statements\AssignStatement;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Token\TokenType;
+namespace MonkeyLang\Lang\Parser\Statements;
+
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Ast\Statements\AssignStatement;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class AssignStatementParser
 {
diff --git a/src/Parser/Statements/BlockStatementParser.php b/src/Lang/Parser/Statements/BlockStatementParser.php
similarity index 75%
rename from src/Parser/Statements/BlockStatementParser.php
rename to src/Lang/Parser/Statements/BlockStatementParser.php
index 85bddd1..0d54c6d 100644
--- a/src/Parser/Statements/BlockStatementParser.php
+++ b/src/Lang/Parser/Statements/BlockStatementParser.php
@@ -2,12 +2,12 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Statements;
+namespace MonkeyLang\Lang\Parser\Statements;
 
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Ast\Statements\Statement;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Ast\Statements\Statement;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class BlockStatementParser
 {
diff --git a/src/Parser/Statements/ExpressionStatementParser.php b/src/Lang/Parser/Statements/ExpressionStatementParser.php
similarity index 67%
rename from src/Parser/Statements/ExpressionStatementParser.php
rename to src/Lang/Parser/Statements/ExpressionStatementParser.php
index 6181b64..f48679e 100644
--- a/src/Parser/Statements/ExpressionStatementParser.php
+++ b/src/Lang/Parser/Statements/ExpressionStatementParser.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Statements;
+namespace MonkeyLang\Lang\Parser\Statements;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Statements\ExpressionStatement;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Statements\ExpressionStatement;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class ExpressionStatementParser
 {
diff --git a/src/Parser/Statements/LetStatementParser.php b/src/Lang/Parser/Statements/LetStatementParser.php
similarity index 72%
rename from src/Parser/Statements/LetStatementParser.php
rename to src/Lang/Parser/Statements/LetStatementParser.php
index 01180f2..25cb50f 100644
--- a/src/Parser/Statements/LetStatementParser.php
+++ b/src/Lang/Parser/Statements/LetStatementParser.php
@@ -2,14 +2,14 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Statements;
-
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Ast\Statements\LetStatement;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Token\TokenType;
+namespace MonkeyLang\Lang\Parser\Statements;
+
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Ast\Statements\LetStatement;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class LetStatementParser
 {
diff --git a/src/Parser/Statements/ReturnStatementParser.php b/src/Lang/Parser/Statements/ReturnStatementParser.php
similarity index 66%
rename from src/Parser/Statements/ReturnStatementParser.php
rename to src/Lang/Parser/Statements/ReturnStatementParser.php
index c6f7b32..ee15495 100644
--- a/src/Parser/Statements/ReturnStatementParser.php
+++ b/src/Lang/Parser/Statements/ReturnStatementParser.php
@@ -2,13 +2,13 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Statements;
+namespace MonkeyLang\Lang\Parser\Statements;
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Statements\ReturnStatement;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\Precedence;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\Precedence;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class ReturnStatementParser
 {
diff --git a/src/Parser/Statements/StatementParser.php b/src/Lang/Parser/Statements/StatementParser.php
similarity index 79%
rename from src/Parser/Statements/StatementParser.php
rename to src/Lang/Parser/Statements/StatementParser.php
index 4614e25..57734e3 100644
--- a/src/Parser/Statements/StatementParser.php
+++ b/src/Lang/Parser/Statements/StatementParser.php
@@ -2,11 +2,11 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Parser\Statements;
+namespace MonkeyLang\Lang\Parser\Statements;
 
-use MonkeyLang\Ast\Statements\Statement;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Statements\Statement;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Token\TokenType;
 
 final class StatementParser
 {
diff --git a/src/Support/StringBuilder.php b/src/Lang/Support/StringBuilder.php
similarity index 95%
rename from src/Support/StringBuilder.php
rename to src/Lang/Support/StringBuilder.php
index 9181a5a..cdc6f9a 100644
--- a/src/Support/StringBuilder.php
+++ b/src/Lang/Support/StringBuilder.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Support;
+namespace MonkeyLang\Lang\Support;
 
 use Stringable;
 
diff --git a/src/Token/Token.php b/src/Lang/Token/Token.php
similarity index 94%
rename from src/Token/Token.php
rename to src/Lang/Token/Token.php
index 40d0f41..2a2d1c3 100644
--- a/src/Token/Token.php
+++ b/src/Lang/Token/Token.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Token;
+namespace MonkeyLang\Lang\Token;
 
 final readonly class Token
 {
diff --git a/src/Token/TokenType.php b/src/Lang/Token/TokenType.php
similarity index 97%
rename from src/Token/TokenType.php
rename to src/Lang/Token/TokenType.php
index ef5f8f6..cc97eee 100644
--- a/src/Token/TokenType.php
+++ b/src/Lang/Token/TokenType.php
@@ -2,10 +2,10 @@
 
 declare(strict_types=1);
 
-namespace MonkeyLang\Token;
+namespace MonkeyLang\Lang\Token;
 
-use MonkeyLang\Lexer\Char;
-use MonkeyLang\Parser\Precedence;
+use MonkeyLang\Lang\Lexer\Char;
+use MonkeyLang\Lang\Parser\Precedence;
 
 enum TokenType: int
 {
diff --git a/src/Monkey/Command/RunFileCommand.php b/src/Monkey/Command/RunFileCommand.php
index dc68017..e678736 100644
--- a/src/Monkey/Command/RunFileCommand.php
+++ b/src/Monkey/Command/RunFileCommand.php
@@ -4,15 +4,15 @@
 
 namespace MonkeyLang\Monkey\Command;
 
-use MonkeyLang\Evaluator\Environment;
-use MonkeyLang\Evaluator\Evaluator;
-use MonkeyLang\Lexer\Lexer;
+use MonkeyLang\Lang\Evaluator\Environment;
+use MonkeyLang\Lang\Evaluator\Evaluator;
+use MonkeyLang\Lang\Lexer\Lexer;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\ProgramParser;
 use MonkeyLang\Monkey\Config\Configuration;
 use MonkeyLang\Monkey\IO\OutputFormatter;
 use MonkeyLang\Monkey\Performance\PerformanceTracker;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\ProgramParser;
 use RuntimeException;
 use Throwable;
 
diff --git a/src/Monkey/IO/OutputFormatter.php b/src/Monkey/IO/OutputFormatter.php
index 9c59006..1b9f112 100644
--- a/src/Monkey/IO/OutputFormatter.php
+++ b/src/Monkey/IO/OutputFormatter.php
@@ -4,9 +4,9 @@
 
 namespace MonkeyLang\Monkey\IO;
 
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\NullObject;
 use MonkeyLang\Monkey\Performance\PerformanceMetrics;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\NullObject;
 use Symfony\Component\Console\Formatter\OutputFormatterStyle;
 use Symfony\Component\Console\Helper\Table;
 use Symfony\Component\Console\Helper\TableStyle;
diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index ab44c64..955eaf1 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -4,17 +4,17 @@
 
 namespace MonkeyLang\Monkey\Repl;
 
-use MonkeyLang\Evaluator\Environment;
-use MonkeyLang\Evaluator\Evaluator;
-use MonkeyLang\Lexer\Lexer;
+use MonkeyLang\Lang\Evaluator\Environment;
+use MonkeyLang\Lang\Evaluator\Evaluator;
+use MonkeyLang\Lang\Lexer\Lexer;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\ProgramParser;
 use MonkeyLang\Monkey\Config\Configuration;
 use MonkeyLang\Monkey\Exceptions\MonkeyRuntimeException;
 use MonkeyLang\Monkey\IO\InputReader;
 use MonkeyLang\Monkey\IO\OutputFormatter;
 use MonkeyLang\Monkey\Performance\PerformanceTracker;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\ProgramParser;
 use Throwable;
 
 use const PHP_OS_FAMILY;
diff --git a/tests/AstTest.php b/tests/AstTest.php
index 8de3107..ddfc408 100644
--- a/tests/AstTest.php
+++ b/tests/AstTest.php
@@ -4,12 +4,12 @@
 
 namespace Tests;
 
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Ast\Program;
-use MonkeyLang\Ast\Statements\LetStatement;
-use MonkeyLang\Ast\Types\IntegerLiteral;
-use MonkeyLang\Token\Token;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Ast\Program;
+use MonkeyLang\Lang\Ast\Statements\LetStatement;
+use MonkeyLang\Lang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Lang\Token\Token;
+use MonkeyLang\Lang\Token\TokenType;
 
 test('to string', function () {
     $program = new Program();
diff --git a/tests/EvaluatorTest.php b/tests/EvaluatorTest.php
index f3f5441..2be2d29 100644
--- a/tests/EvaluatorTest.php
+++ b/tests/EvaluatorTest.php
@@ -4,16 +4,16 @@
 
 namespace Tests;
 
-use MonkeyLang\Object\ArrayObject;
-use MonkeyLang\Object\BooleanObject;
-use MonkeyLang\Object\ErrorObject;
-use MonkeyLang\Object\FloatObject;
-use MonkeyLang\Object\FunctionObject;
-use MonkeyLang\Object\IntegerObject;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Object\MonkeyObjectType;
-use MonkeyLang\Object\NullObject;
-use MonkeyLang\Object\StringObject;
+use MonkeyLang\Lang\Object\ArrayObject;
+use MonkeyLang\Lang\Object\BooleanObject;
+use MonkeyLang\Lang\Object\ErrorObject;
+use MonkeyLang\Lang\Object\FloatObject;
+use MonkeyLang\Lang\Object\FunctionObject;
+use MonkeyLang\Lang\Object\IntegerObject;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Object\MonkeyObjectType;
+use MonkeyLang\Lang\Object\NullObject;
+use MonkeyLang\Lang\Object\StringObject;
 
 function testObjectValue(MonkeyObject $object, $expected)
 {
diff --git a/tests/Helpers.php b/tests/Helpers.php
index 47ba4a9..ece3ad6 100644
--- a/tests/Helpers.php
+++ b/tests/Helpers.php
@@ -2,16 +2,16 @@
 
 declare(strict_types=1);
 
-use MonkeyLang\Ast\Expressions\Expression;
-use MonkeyLang\Ast\Program;
-use MonkeyLang\Ast\Types\BooleanLiteral;
-use MonkeyLang\Ast\Types\IntegerLiteral;
-use MonkeyLang\Evaluator\Environment;
-use MonkeyLang\Evaluator\Evaluator;
-use MonkeyLang\Lexer\Lexer;
-use MonkeyLang\Object\MonkeyObject;
-use MonkeyLang\Parser\Parser;
-use MonkeyLang\Parser\ProgramParser;
+use MonkeyLang\Lang\Ast\Expressions\Expression;
+use MonkeyLang\Lang\Ast\Program;
+use MonkeyLang\Lang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Lang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Lang\Evaluator\Environment;
+use MonkeyLang\Lang\Evaluator\Evaluator;
+use MonkeyLang\Lang\Lexer\Lexer;
+use MonkeyLang\Lang\Object\MonkeyObject;
+use MonkeyLang\Lang\Parser\Parser;
+use MonkeyLang\Lang\Parser\ProgramParser;
 
 function assertInfixExpression(Expression $expression, $leftValue, string $operator, $rightValue): void
 {
diff --git a/tests/LexerTest.php b/tests/LexerTest.php
index 1cc1e06..67868a1 100644
--- a/tests/LexerTest.php
+++ b/tests/LexerTest.php
@@ -4,8 +4,8 @@
 
 namespace Tests;
 
-use MonkeyLang\Lexer\Lexer;
-use MonkeyLang\Token\TokenType;
+use MonkeyLang\Lang\Lexer\Lexer;
+use MonkeyLang\Lang\Token\TokenType;
 
 test('basic tokens', function () {
     $input = <<<MONKEY
diff --git a/tests/ParserTest.php b/tests/ParserTest.php
index 95f26d5..89f439c 100644
--- a/tests/ParserTest.php
+++ b/tests/ParserTest.php
@@ -4,24 +4,24 @@
 
 namespace Tests;
 
-use MonkeyLang\Ast\Expressions\BinaryExpression;
-use MonkeyLang\Ast\Expressions\CallExpression;
-use MonkeyLang\Ast\Expressions\IdentifierExpression;
-use MonkeyLang\Ast\Expressions\IfExpression;
-use MonkeyLang\Ast\Expressions\IndexExpression;
-use MonkeyLang\Ast\Expressions\PostfixExpression;
-use MonkeyLang\Ast\Expressions\UnaryExpression;
-use MonkeyLang\Ast\Expressions\WhileExpression;
-use MonkeyLang\Ast\Statements\AssignStatement;
-use MonkeyLang\Ast\Statements\BlockStatement;
-use MonkeyLang\Ast\Statements\ExpressionStatement;
-use MonkeyLang\Ast\Statements\LetStatement;
-use MonkeyLang\Ast\Statements\ReturnStatement;
-use MonkeyLang\Ast\Types\ArrayLiteral;
-use MonkeyLang\Ast\Types\BooleanLiteral;
-use MonkeyLang\Ast\Types\FunctionLiteral;
-use MonkeyLang\Ast\Types\IntegerLiteral;
-use MonkeyLang\Ast\Types\StringLiteral;
+use MonkeyLang\Lang\Ast\Expressions\BinaryExpression;
+use MonkeyLang\Lang\Ast\Expressions\CallExpression;
+use MonkeyLang\Lang\Ast\Expressions\IdentifierExpression;
+use MonkeyLang\Lang\Ast\Expressions\IfExpression;
+use MonkeyLang\Lang\Ast\Expressions\IndexExpression;
+use MonkeyLang\Lang\Ast\Expressions\PostfixExpression;
+use MonkeyLang\Lang\Ast\Expressions\UnaryExpression;
+use MonkeyLang\Lang\Ast\Expressions\WhileExpression;
+use MonkeyLang\Lang\Ast\Statements\AssignStatement;
+use MonkeyLang\Lang\Ast\Statements\BlockStatement;
+use MonkeyLang\Lang\Ast\Statements\ExpressionStatement;
+use MonkeyLang\Lang\Ast\Statements\LetStatement;
+use MonkeyLang\Lang\Ast\Statements\ReturnStatement;
+use MonkeyLang\Lang\Ast\Types\ArrayLiteral;
+use MonkeyLang\Lang\Ast\Types\BooleanLiteral;
+use MonkeyLang\Lang\Ast\Types\FunctionLiteral;
+use MonkeyLang\Lang\Ast\Types\IntegerLiteral;
+use MonkeyLang\Lang\Ast\Types\StringLiteral;
 
 test('let statements', function (string $input, string $name, $value) {
     $program = newProgram($input);

From 090aea12eb52e42c960cc0de9a468698d7d97232 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 12:47:08 -0300
Subject: [PATCH 08/22] Update Monkey.php

---
 src/Monkey/Monkey.php | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Monkey/Monkey.php b/src/Monkey/Monkey.php
index a123547..bd84f7f 100644
--- a/src/Monkey/Monkey.php
+++ b/src/Monkey/Monkey.php
@@ -25,6 +25,9 @@ public static function version(): string
         return self::VERSION;
     }
 
+    /**
+     * @param array<string> $argv
+     */
     public function run(array $argv): int
     {
         try {

From f7fe5d2a34ce4517795a7a6e4859e386760907c0 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 12:48:00 -0300
Subject: [PATCH 09/22] Update VersionCommand.php

---
 src/Monkey/Command/VersionCommand.php | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Monkey/Command/VersionCommand.php b/src/Monkey/Command/VersionCommand.php
index ba06153..a822b65 100644
--- a/src/Monkey/Command/VersionCommand.php
+++ b/src/Monkey/Command/VersionCommand.php
@@ -6,6 +6,7 @@
 
 use MonkeyLang\Monkey\Config\Configuration;
 use MonkeyLang\Monkey\IO\OutputFormatter;
+use MonkeyLang\Monkey\Monkey;
 
 final readonly class VersionCommand implements Command
 {
@@ -16,7 +17,7 @@ public function __construct(
 
     public function execute(Configuration $config): int
     {
-        $this->outputFormatter->write('Monkey Programming Language v 1.0');
+        $this->outputFormatter->write('Monkey Programming Language v' . Monkey::version());
 
         return 0;
     }

From bfad30f832db18588d1f5dde2410c8131d1ec87e Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:02:07 -0300
Subject: [PATCH 10/22] Chore

---
 monkey                                     | 15 +++++++++++----
 src/Monkey/Command/CommandFactory.php      |  7 +++----
 src/Monkey/Config/Configuration.php        |  6 ++++++
 src/Monkey/Config/ConfigurationManager.php | 11 +++++++----
 4 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/monkey b/monkey
index 11f4a97..0369741 100755
--- a/monkey
+++ b/monkey
@@ -21,7 +21,12 @@ if (PHP_SAPI !== 'cli') {
     exit;
 }
 
-if (!isset($GLOBALS['argv']) || !is_array($GLOBALS['argv'])) {
+/**
+ * @var array<string> $argv
+ */
+$argv = (array) ($GLOBALS['argv'] ?? []);
+
+if ($argv === []) {
     exit(1);
 }
 
@@ -33,6 +38,7 @@ try {
     $outputFormatter = new OutputFormatter($output);
     $inputReader = new InputReader($input, $output, $questionHelper);
     $performanceTracker = new PerformanceTracker();
+    
     $replManager = new ReplManager(
         $inputReader,
         $outputFormatter,
@@ -40,16 +46,17 @@ try {
     );
 
     $commandFactory = new CommandFactory(
-        //$inputReader,
         $outputFormatter,
         $performanceTracker,
         $replManager
     );
-    $commandRunner = new CommandRunner($commandFactory);
+
     $configManager = new ConfigurationManager();
+    $commandRunner = new CommandRunner($commandFactory);
 
     $monkey = new Monkey($commandRunner, $configManager);
-    exit($monkey->run($GLOBALS['argv']));
+    
+    exit($monkey->run($argv));
 } catch (Throwable $e) {
     fwrite(STDERR, "Fatal error: {$e->getMessage()}\n");
     exit(1);
diff --git a/src/Monkey/Command/CommandFactory.php b/src/Monkey/Command/CommandFactory.php
index fa72b52..face96c 100644
--- a/src/Monkey/Command/CommandFactory.php
+++ b/src/Monkey/Command/CommandFactory.php
@@ -11,6 +11,7 @@
 
 final class CommandFactory
 {
+    /** @var array<string, Command> */
     private array $commands = [];
 
     public function __construct(
@@ -35,10 +36,8 @@ private function registerCommands(): void
         $this->commands = [
             'repl' => new ReplCommand($this->replManager, $this->outputFormatter),
             'run' => new RunFileCommand($this->outputFormatter, $this->performanceTracker),
-            '--help' => new HelpCommand($this->outputFormatter),
-            '-h' => new HelpCommand($this->outputFormatter),
-            '--version' => new VersionCommand($this->outputFormatter),
-            '-v' => new VersionCommand($this->outputFormatter),
+            'help' => new HelpCommand($this->outputFormatter),
+            'version' => new VersionCommand($this->outputFormatter),
         ];
     }
 }
diff --git a/src/Monkey/Config/Configuration.php b/src/Monkey/Config/Configuration.php
index 56eabe7..2845fb3 100644
--- a/src/Monkey/Config/Configuration.php
+++ b/src/Monkey/Config/Configuration.php
@@ -8,7 +8,13 @@
 {
     public function __construct(
         public string $command,
+        /**
+         * @var array<string, mixed>
+         */
         public array $options,
+        /**
+         * @var array<string>
+         */
         public array $arguments,
     ) {
     }
diff --git a/src/Monkey/Config/ConfigurationManager.php b/src/Monkey/Config/ConfigurationManager.php
index 5f1d835..dcaab1a 100644
--- a/src/Monkey/Config/ConfigurationManager.php
+++ b/src/Monkey/Config/ConfigurationManager.php
@@ -11,10 +11,13 @@
 
 final class ConfigurationManager
 {
-    private const array VALID_COMMANDS = ['repl', 'run', '--version', '-v', '--help', '-h'];
+    private const array VALID_COMMANDS = ['repl', 'run', 'version', 'help'];
 
     private const array VALID_OPTIONS = ['--debug', '--stats'];
 
+    /**
+     * @param array<string> $argv
+     */
     public function parseArguments(array $argv): Configuration
     {
         if (count($argv) <= 1) {
@@ -28,14 +31,14 @@ public function parseArguments(array $argv): Configuration
         foreach ($argv as $index => $arg) {
             if ($index === 0) {
                 continue;
-            } // Skip script name
+            }
 
-            if (str_starts_with((string)$arg, '--')) {
+            if (str_starts_with($arg, '--')) {
                 if (!in_array($arg, self::VALID_OPTIONS)) {
                     throw new RuntimeException("Invalid option: {$arg}");
                 }
 
-                $options[trim((string)$arg, '-')] = true;
+                $options[trim($arg, '-')] = true;
             } elseif ($command === '') {
                 if (!in_array($arg, self::VALID_COMMANDS)) {
                     throw new RuntimeException("Invalid command: {$arg}");

From 8571456644374dc89e2a1b81e5075262ededd77d Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:03:39 -0300
Subject: [PATCH 11/22] Chore

---
 monkey     | 1 +
 rector.php | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/monkey b/monkey
index 0369741..68810de 100755
--- a/monkey
+++ b/monkey
@@ -59,5 +59,6 @@ try {
     exit($monkey->run($argv));
 } catch (Throwable $e) {
     fwrite(STDERR, "Fatal error: {$e->getMessage()}\n");
+    
     exit(1);
 }
diff --git a/rector.php b/rector.php
index 7b89131..83f8d0a 100644
--- a/rector.php
+++ b/rector.php
@@ -3,6 +3,7 @@
 declare(strict_types=1);
 
 use Rector\CodingStyle\Rector\Encapsed\EncapsedStringsToSprintfRector;
+use Rector\CodingStyle\Rector\PostInc\PostIncDecToPreIncDecRector;
 use Rector\Config\RectorConfig;
 use Rector\Set\ValueObject\LevelSetList;
 
@@ -29,6 +30,7 @@
     ])
     ->withSkip([
         EncapsedStringsToSprintfRector::class,
+        PostIncDecToPreIncDecRector::class,
     ])
     ->withPaths([
         __DIR__ . '/src',

From 49cc7d138e1d72affa5de847e4eafaae255589a8 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:05:30 -0300
Subject: [PATCH 12/22] Update ConfigurationManager.php

---
 src/Monkey/Config/ConfigurationManager.php | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/src/Monkey/Config/ConfigurationManager.php b/src/Monkey/Config/ConfigurationManager.php
index dcaab1a..f45cc05 100644
--- a/src/Monkey/Config/ConfigurationManager.php
+++ b/src/Monkey/Config/ConfigurationManager.php
@@ -21,7 +21,7 @@ final class ConfigurationManager
     public function parseArguments(array $argv): Configuration
     {
         if (count($argv) <= 1) {
-            throw new RuntimeException('No command specified');
+            $argv[] = 'help';
         }
 
         $options = [];
@@ -50,11 +50,6 @@ public function parseArguments(array $argv): Configuration
             }
         }
 
-        // If no command was found after processing options
-        if ($command === '') {
-            $command = '--help';
-        }
-
         return new Configuration($command, $options, $arguments);
     }
 }

From 9bc4ae77cd5694d51efef464bf42a0918a0f89d5 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:07:44 -0300
Subject: [PATCH 13/22] Update CommandFactory.php

---
 src/Monkey/Command/CommandFactory.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Monkey/Command/CommandFactory.php b/src/Monkey/Command/CommandFactory.php
index face96c..8941b08 100644
--- a/src/Monkey/Command/CommandFactory.php
+++ b/src/Monkey/Command/CommandFactory.php
@@ -34,7 +34,7 @@ public function create(string $commandName): Command
     private function registerCommands(): void
     {
         $this->commands = [
-            'repl' => new ReplCommand($this->replManager, $this->outputFormatter),
+            'repl' => new ReplCommand($this->replManager),
             'run' => new RunFileCommand($this->outputFormatter, $this->performanceTracker),
             'help' => new HelpCommand($this->outputFormatter),
             'version' => new VersionCommand($this->outputFormatter),

From a12fbf3b8e271195d160f0c077d16863615b638d Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:11:04 -0300
Subject: [PATCH 14/22] Update ReplManager.php

---
 src/Monkey/Repl/ReplManager.php | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 955eaf1..25d1bad 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -35,7 +35,11 @@ final class ReplManager
         ':reset' => 'handleResetEnvironment',
     ];
 
-    private bool $debugMode = false;
+    private bool $debugMode = false {
+        get {
+            return $this->debugMode;
+        }
+    }
 
     private bool $running = true;
 
@@ -43,7 +47,11 @@ public function __construct(
         private readonly InputReader $inputReader,
         private readonly OutputFormatter $outputFormatter,
         private readonly PerformanceTracker $performanceTracker,
-        private Environment $environment = new Environment(),
+        private Environment $environment = new Environment() {
+            get {
+                return $this->environment;
+            }
+        },
         private readonly Evaluator $evaluator = new Evaluator(),
     ) {
     }
@@ -55,7 +63,7 @@ public function start(Configuration $config): int
             $this->showWelcomeBanner();
 
             while ($this->running) {
-                $this->outputFormatter->write(''); // Add newline before prompt
+                $this->outputFormatter->write('');
                 $input = $this->inputReader->readLine();
 
                 if ($input === false) {
@@ -97,16 +105,6 @@ public function start(Configuration $config): int
         }
     }
 
-    public function isDebugMode(): bool
-    {
-        return $this->debugMode;
-    }
-
-    public function getEnvironment(): Environment
-    {
-        return $this->environment;
-    }
-
     private function evaluateAndOutput(string $input, Configuration $config): void
     {
         if ($config->hasStats()) {

From 252e0daa24687d2f30a08fef87b645a5ce92c1d6 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:25:16 -0300
Subject: [PATCH 15/22] chore

---
 src/Monkey/IO/OutputFormatter.php |  2 +-
 src/Monkey/Repl/ReplManager.php   | 93 +++++++++----------------------
 2 files changed, 27 insertions(+), 68 deletions(-)

diff --git a/src/Monkey/IO/OutputFormatter.php b/src/Monkey/IO/OutputFormatter.php
index 1b9f112..abfcd87 100644
--- a/src/Monkey/IO/OutputFormatter.php
+++ b/src/Monkey/IO/OutputFormatter.php
@@ -20,7 +20,7 @@
 final readonly class OutputFormatter
 {
     public function __construct(
-        private OutputInterface $output,
+        private(set) OutputInterface $output,
     ) {
         $this->configureStyles();
     }
diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 25d1bad..856c13c 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -15,26 +15,15 @@
 use MonkeyLang\Monkey\IO\InputReader;
 use MonkeyLang\Monkey\IO\OutputFormatter;
 use MonkeyLang\Monkey\Performance\PerformanceTracker;
+use Symfony\Component\Console\Helper\Table;
+use Symfony\Component\Console\Helper\TableStyle;
 use Throwable;
 
+
 use const PHP_OS_FAMILY;
 
 final class ReplManager
 {
-    private const array SPECIAL_COMMANDS = [
-        ':q' => 'handleQuit',
-        ':quit' => 'handleQuit',
-        'exit' => 'handleQuit',
-        ':h' => 'handleHelp',
-        ':help' => 'handleHelp',
-        ':c' => 'handleClear',
-        ':clear' => 'handleClear',
-        ':d' => 'handleDebugToggle',
-        ':debug' => 'handleDebugToggle',
-        ':r' => 'handleResetEnvironment',
-        ':reset' => 'handleResetEnvironment',
-    ];
-
     private bool $debugMode = false {
         get {
             return $this->debugMode;
@@ -133,7 +122,7 @@ private function evaluate(string $input): MonkeyObject
             );
         }
 
-        $program = (new ProgramParser())($parser);
+        $program = new ProgramParser()($parser);
 
         return $this->evaluator->eval($program, $this->environment);
     }
@@ -142,10 +131,15 @@ private function handleSpecialCommand(string $input): bool
     {
         $trimmedInput = trim($input);
 
-        if (isset(self::SPECIAL_COMMANDS[$trimmedInput])) {
-            $method = self::SPECIAL_COMMANDS[$trimmedInput];
+        $commands = [
+            ':q' => fn(): bool => $this->handleQuit(),
+            ':quit' => fn(): bool => $this->handleQuit(),
+            ':c' => fn(): bool => $this->handleClear(),
+            ':clear' => fn(): bool => $this->handleClear(),
+        ];
 
-            return $this->{$method}();
+        if (isset($commands[$trimmedInput])) {
+            return $commands[$trimmedInput]();
         }
 
         return false;
@@ -159,22 +153,6 @@ private function handleQuit(): bool
         return true;
     }
 
-    private function handleHelp(): bool
-    {
-        $this->outputFormatter->write(<<<HELP
-        \nMonkey REPL Commands:
-        :q, :quit, exit   Exit the REPL
-        :h, :help         Show this help message
-        :c, :clear        Clear the screen
-        :d, :debug        Toggle debug mode
-        :r, :reset        Reset the environment
-
-        Press Ctrl+C to cancel current input
-        HELP);
-
-        return true;
-    }
-
     private function handleClear(): bool
     {
         if (PHP_OS_FAMILY === 'Windows') {
@@ -188,44 +166,25 @@ private function handleClear(): bool
         return true;
     }
 
-    private function handleDebugToggle(): bool
+    private function showWelcomeBanner(): void
     {
-        $this->debugMode = !$this->debugMode;
-        $this->outputFormatter->write(
-            'Debug mode: ' . ($this->debugMode ? 'Enabled' : 'Disabled'),
-        );
+        $tableStyle = new TableStyle();
+        $tableStyle
+            ->setHorizontalBorderChars('-')
+            ->setVerticalBorderChars('|')
+            ->setCrossingChars('+', '+', '+', '+', '+', '+', '+', '+', '+')
+            ->setPadType(STR_PAD_RIGHT);
 
-        return true;
-    }
+        $table = new Table($this->outputFormatter->output);
+        $table->setStyle($tableStyle);
 
-    private function handleResetEnvironment(): bool
-    {
-        $this->environment = new Environment();
-        $this->outputFormatter->write('Environment has been reset');
+        $table->setRows([
+            ['🐒 Monkey Programming Language v1.0.0'],
+            ["Type ':c' for clear, ':q' to quit"],
+        ]);
 
-        return true;
-    }
+        $table->render();
 
-    private function showWelcomeBanner(): void
-    {
-        $this->outputFormatter->write(<<<BANNER
-                    __,__
-           .--.  .-"     "-.  .--.
-          / .. \\/  .-. .-.  \\/ .. \\
-         | |  '|  /   Y   \\  |'  | |
-         | \\   \\  \\ 0 | 0 /  /   / |
-          \\ '- ,\\.-"`` ``"-./, -' /
-           `'-' /_   ^ ^   _\\ '-'`
-               |  \\._   _./  |
-               \\   \\ `~` /   /
-                '._ '-=-' _.'
-                   '~---~'
-        -------------------------------
-        | Monkey Programming Language |
-        -------------------------------
-
-        Type ':h' for help, ':c' for clear, ':q' to quit
-        BANNER);
         $this->outputFormatter->write('');
     }
 }

From c0afb181214bd7d6dad30f20aed46d6315ef918c Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:26:14 -0300
Subject: [PATCH 16/22] Update rector.php

---
 rector.php | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/rector.php b/rector.php
index 83f8d0a..865b8df 100644
--- a/rector.php
+++ b/rector.php
@@ -5,6 +5,7 @@
 use Rector\CodingStyle\Rector\Encapsed\EncapsedStringsToSprintfRector;
 use Rector\CodingStyle\Rector\PostInc\PostIncDecToPreIncDecRector;
 use Rector\Config\RectorConfig;
+use Rector\Php81\Rector\Property\ReadOnlyPropertyRector;
 use Rector\Set\ValueObject\LevelSetList;
 
 return RectorConfig::configure()
@@ -31,6 +32,7 @@
     ->withSkip([
         EncapsedStringsToSprintfRector::class,
         PostIncDecToPreIncDecRector::class,
+        ReadOnlyPropertyRector::class,
     ])
     ->withPaths([
         __DIR__ . '/src',

From 588f5f1d30f244a360df52833013ccee19656e81 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:27:18 -0300
Subject: [PATCH 17/22] Update ReplManager.php

---
 src/Monkey/Repl/ReplManager.php | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 856c13c..5e3d573 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -168,15 +168,7 @@ private function handleClear(): bool
 
     private function showWelcomeBanner(): void
     {
-        $tableStyle = new TableStyle();
-        $tableStyle
-            ->setHorizontalBorderChars('-')
-            ->setVerticalBorderChars('|')
-            ->setCrossingChars('+', '+', '+', '+', '+', '+', '+', '+', '+')
-            ->setPadType(STR_PAD_RIGHT);
-
         $table = new Table($this->outputFormatter->output);
-        $table->setStyle($tableStyle);
 
         $table->setRows([
             ['🐒 Monkey Programming Language v1.0.0'],

From fa9e6ebe4561136207b465a13152a2f3401f2832 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:28:00 -0300
Subject: [PATCH 18/22] Chore

---
 src/Monkey/IO/OutputFormatter.php | 11 -----------
 src/Monkey/Repl/ReplManager.php   |  1 -
 2 files changed, 12 deletions(-)

diff --git a/src/Monkey/IO/OutputFormatter.php b/src/Monkey/IO/OutputFormatter.php
index abfcd87..33fa948 100644
--- a/src/Monkey/IO/OutputFormatter.php
+++ b/src/Monkey/IO/OutputFormatter.php
@@ -9,14 +9,11 @@
 use MonkeyLang\Monkey\Performance\PerformanceMetrics;
 use Symfony\Component\Console\Formatter\OutputFormatterStyle;
 use Symfony\Component\Console\Helper\Table;
-use Symfony\Component\Console\Helper\TableStyle;
 use Symfony\Component\Console\Output\OutputInterface;
 
 use function count;
 use function sprintf;
 
-use const STR_PAD_RIGHT;
-
 final readonly class OutputFormatter
 {
     public function __construct(
@@ -56,15 +53,7 @@ public function writePerformanceStats(PerformanceMetrics $metrics): void
         $this->output->writeln('');
         $this->output->writeln('<title>Performance Statistics</title>');
 
-        $tableStyle = new TableStyle();
-        $tableStyle
-            ->setHorizontalBorderChars('-')
-            ->setVerticalBorderChars('|')
-            ->setCrossingChars('+', '+', '+', '+', '+', '+', '+', '+', '+')
-            ->setPadType(STR_PAD_RIGHT);
-
         $table = new Table($this->output);
-        $table->setStyle($tableStyle);
 
         $table->setRows([
             ['Memory used', "<memory>{$this->formatBytes($metrics->memoryUsed)}</memory>"],
diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 5e3d573..4845e55 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -16,7 +16,6 @@
 use MonkeyLang\Monkey\IO\OutputFormatter;
 use MonkeyLang\Monkey\Performance\PerformanceTracker;
 use Symfony\Component\Console\Helper\Table;
-use Symfony\Component\Console\Helper\TableStyle;
 use Throwable;
 
 

From ecddc343e76bb13d903d45963705ffd35f7bfff5 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:32:04 -0300
Subject: [PATCH 19/22] Chore

---
 monkey                                | 17 ++++++++++-------
 src/Monkey/Command/CommandFactory.php |  2 +-
 src/Monkey/Repl/ReplManager.php       |  6 ++++--
 3 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/monkey b/monkey
index 68810de..c085e2d 100755
--- a/monkey
+++ b/monkey
@@ -40,21 +40,24 @@ try {
     $performanceTracker = new PerformanceTracker();
     
     $replManager = new ReplManager(
-        $inputReader,
-        $outputFormatter,
-        $performanceTracker
+        inputReader: $inputReader,
+        outputFormatter: $outputFormatter,
+        performanceTracker: $performanceTracker
     );
 
     $commandFactory = new CommandFactory(
-        $outputFormatter,
-        $performanceTracker,
-        $replManager
+        replManager: $replManager,
+        outputFormatter: $outputFormatter,
+        performanceTracker: $performanceTracker
     );
 
     $configManager = new ConfigurationManager();
     $commandRunner = new CommandRunner($commandFactory);
 
-    $monkey = new Monkey($commandRunner, $configManager);
+    $monkey = new Monkey(
+        commandRunner: $commandRunner, 
+        configManager: $configManager
+    );
     
     exit($monkey->run($argv));
 } catch (Throwable $e) {
diff --git a/src/Monkey/Command/CommandFactory.php b/src/Monkey/Command/CommandFactory.php
index 8941b08..3d0fbe0 100644
--- a/src/Monkey/Command/CommandFactory.php
+++ b/src/Monkey/Command/CommandFactory.php
@@ -15,9 +15,9 @@ final class CommandFactory
     private array $commands = [];
 
     public function __construct(
+        private readonly ReplManager $replManager,
         private readonly OutputFormatter $outputFormatter,
         private readonly PerformanceTracker $performanceTracker,
-        private readonly ReplManager $replManager,
     ) {
         $this->registerCommands();
     }
diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 4845e55..5d718c0 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -55,7 +55,8 @@ public function start(Configuration $config): int
                 $input = $this->inputReader->readLine();
 
                 if ($input === false) {
-                    $this->outputFormatter->write("\nGoodbye!");
+                    $this->outputFormatter->write('');
+                    $this->outputFormatter->write("Goodbye!");
 
                     return 0;
                 }
@@ -147,7 +148,8 @@ private function handleSpecialCommand(string $input): bool
     private function handleQuit(): bool
     {
         $this->running = false;
-        $this->outputFormatter->write('Goodbye!');
+        $this->outputFormatter->write('');
+        $this->outputFormatter->write("Goodbye!");
 
         return true;
     }

From db1a349891d6c45441a219363cdfbb3cb0d0c9bb Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:35:27 -0300
Subject: [PATCH 20/22] Chore

---
 src/Monkey/IO/InputReader.php   |  2 +-
 src/Monkey/Repl/ReplManager.php | 11 ++++++-----
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/Monkey/IO/InputReader.php b/src/Monkey/IO/InputReader.php
index ff3452b..1971434 100644
--- a/src/Monkey/IO/InputReader.php
+++ b/src/Monkey/IO/InputReader.php
@@ -23,7 +23,7 @@ public function __construct(
 
     public function readLine(string $prompt = '➜ '): string | false
     {
-        $question = new Question("<prompt>{$prompt}</prompt> ");
+        $question = new Question($prompt);
 
         try {
             $answer = $this->questionHelper->ask($this->input, $this->output, $question);
diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 5d718c0..5f48ff4 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -48,7 +48,7 @@ public function start(Configuration $config): int
     {
         try {
             $this->debugMode = $config->hasDebug();
-            $this->showWelcomeBanner();
+            $this->welcome();
 
             while ($this->running) {
                 $this->outputFormatter->write('');
@@ -162,18 +162,19 @@ private function handleClear(): bool
             system('clear');
         }
 
-        $this->showWelcomeBanner();
+        $this->welcome();
 
         return true;
     }
 
-    private function showWelcomeBanner(): void
+    private function welcome(): void
     {
         $table = new Table($this->outputFormatter->output);
 
         $table->setRows([
-            ['🐒 Monkey Programming Language v1.0.0'],
-            ["Type ':c' for clear, ':q' to quit"],
+            ['<fg=green>🐒 Monkey Programming Language</> <fg=yellow>v1.0.0</>'],
+            [''],
+            ["<fg=cyan>Type</> <fg=blue>:c</> <fg=cyan>for clear,</> <fg=blue>:q</> <fg=cyan>to quit</>"],
         ]);
 
         $table->render();

From 05d6c30a5c93f841ef681649cef33dda32b0b9eb Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:37:02 -0300
Subject: [PATCH 21/22] Update ReplManager.php

---
 src/Monkey/Repl/ReplManager.php | 25 +++++++++----------------
 1 file changed, 9 insertions(+), 16 deletions(-)

diff --git a/src/Monkey/Repl/ReplManager.php b/src/Monkey/Repl/ReplManager.php
index 5f48ff4..26137e2 100644
--- a/src/Monkey/Repl/ReplManager.php
+++ b/src/Monkey/Repl/ReplManager.php
@@ -65,7 +65,7 @@ public function start(Configuration $config): int
                     continue;
                 }
 
-                if ($this->handleSpecialCommand($input)) {
+                if ($this->runCommand($input)) {
                     continue;
                 }
 
@@ -127,25 +127,18 @@ private function evaluate(string $input): MonkeyObject
         return $this->evaluator->eval($program, $this->environment);
     }
 
-    private function handleSpecialCommand(string $input): bool
+    private function runCommand(string $input): bool
     {
         $trimmedInput = trim($input);
 
-        $commands = [
-            ':q' => fn(): bool => $this->handleQuit(),
-            ':quit' => fn(): bool => $this->handleQuit(),
-            ':c' => fn(): bool => $this->handleClear(),
-            ':clear' => fn(): bool => $this->handleClear(),
-        ];
-
-        if (isset($commands[$trimmedInput])) {
-            return $commands[$trimmedInput]();
-        }
-
-        return false;
+        return match ($trimmedInput) {
+            ':q', ':quit' => $this->quit(),
+            ':c', ':clear' => $this->clear(),
+            default => false,
+        };
     }
 
-    private function handleQuit(): bool
+    private function quit(): bool
     {
         $this->running = false;
         $this->outputFormatter->write('');
@@ -154,7 +147,7 @@ private function handleQuit(): bool
         return true;
     }
 
-    private function handleClear(): bool
+    private function clear(): bool
     {
         if (PHP_OS_FAMILY === 'Windows') {
             system('cls');

From fd20de5ef6813cb5040a8c5fb69d490fe8472bb1 Mon Sep 17 00:00:00 2001
From: Kennedy Tedesco <kennedyt.tw@gmail.com>
Date: Sun, 15 Dec 2024 13:38:45 -0300
Subject: [PATCH 22/22] Update README.md

---
 README.md | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 1d28e14..3528864 100644
--- a/README.md
+++ b/README.md
@@ -144,7 +144,7 @@ docker run --rm -v $(pwd):/monkey -w /monkey php:8.4-cli ./vendor/bin/pest
 Running from a file contents of the examples folder:
 
 ```bash
-docker run --rm -v (pwd):/monkey -w /monkey php:8.4-cli ./monkey run examples/fibo_while.monkey
+docker run --rm -v (pwd):/monkey -w /monkey php:8.4-cli ./monkey --stats run examples/fibo_while.monkey
 ```
 
 ### Using the REPL
@@ -158,17 +158,23 @@ docker run -it --rm -v (pwd):/monkey -w /monkey php:8.4-cli ./monkey repl
 Example:
 
 ```text
-🐒 Monkey Programming Language v1.0.0
-Type ':h' for help, ':c' for clear, ':q' to quit
++---------------------------------------+
+| 🐒 Monkey Programming Language v1.0.0 |
+|                                       |
+| Type :c for clear, :q to quit         |
++---------------------------------------+
+
 
 ➜ let a = 20 + fn(x){ return x + 10; }(2);
 32
+
+➜
 ```
 
 Or, if you want to execute a file:
 
 ```bash
-docker run --rm -v (pwd):/monkey -w /monkey php:8.4-cli ./monkey run examples/closure.monkey
+docker run --rm -v (pwd):/monkey -w /monkey php:8.4-cli ./monkey --stats run examples/closure.monkey
 ```
 
 ### Contributing