diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
new file mode 100644
index 0000000..8e74283
--- /dev/null
+++ b/.github/workflows/tests.yml
@@ -0,0 +1,46 @@
+name: Tests
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  tests:
+    name: PHP ${{ matrix.php-version }}
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        php-version:
+          - '8.2'
+          - '8.3'
+          - '8.4'
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php-version }}
+          extensions: sockets, json, pdo
+          coverage: none
+
+      - name: Install dependencies
+        run: composer install --no-interaction --prefer-dist
+
+      - name: Validate Composer package
+        run: composer validate --strict
+
+      - name: Check code style
+        run: composer cs:check
+
+      - name: Run static analysis
+        run: composer analyse
+
+      - name: Run tests
+        run: composer test
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..776c70d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,42 @@
+/vendor/
+/composer.lock
+
+/.phpunit.cache/
+/.php-cs-fixer.cache
+/.phpstan.cache
+/coverage/
+/build/
+/dist/
+
+.zip
+.env
+.env.*
+!.env.example
+
+*.log
+*.tmp
+*.temp
+*.cache
+
+.DS_Store
+Thumbs.db
+desktop.ini
+
+.idea/
+.vscode/
+*.sublime-project
+*.sublime-workspace
+
+.phpunit.result.cache
+
+/storage/*.sqlite
+/storage/*.sqlite3
+/storage/*.db
+
+node_modules/
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+
+/.phpunit.cache
\ No newline at end of file
diff --git a/.php-cs-fixer.php b/.php-cs-fixer.php
new file mode 100644
index 0000000..ec5670b
--- /dev/null
+++ b/.php-cs-fixer.php
@@ -0,0 +1,18 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()
+    ->in(__DIR__ . '/src')
+    ->in(__DIR__ . '/tests')
+    ->name('*.php');
+
+return (new PhpCsFixer\Config())
+    ->setRiskyAllowed(true)
+    ->setRules([
+        '@PSR12' => true,
+        'array_syntax' => ['syntax' => 'short'],
+        'declare_strict_types' => true,
+        'no_unused_imports' => true,
+        'ordered_imports' => ['sort_algorithm' => 'alpha'],
+        'single_quote' => true,
+    ])
+    ->setFinder($finder);
\ No newline at end of file
diff --git a/README.md b/README.md
index 3acde32..f660ceb 100644
--- a/README.md
+++ b/README.md
@@ -1,20 +1,116 @@
 # PHPSockets With WebSockets
 
-PHPSockets With WebSockets is being reborn as a modern native PHP WebSocket and realtime chat library.
+> **Maintenance notice:** this repository is being actively rebuilt as a modern native PHP WebSocket and realtime chat library. The legacy 2016 implementation is preserved for historical reference, while the new Composer-based library is being implemented phase by phase.
 
-The original project was created in 2016 as a simple educational experiment showing how to build a WebSocket server with PHP sockets, without Node.js and without socket.io.
+PHPSockets With WebSockets was originally created in 2016 as an educational experiment showing how to build a WebSocket server with PHP sockets, without Node.js and without socket.io.
 
-This repository is now being progressively redesigned as a Composer package with a clean architecture, modern PHP support, examples, tests, storage adapters, CLI commands, Laravel integration, and a stronger chat-focused developer experience.
+The project is now being progressively redesigned as a Composer package with a clean architecture, modern PHP support, examples, tests, storage adapters, CLI commands, optional Laravel integration, and a stronger chat-focused developer experience.
 
 ## Current status
 
-This repository is currently in the legacy preservation phase.
+The project is currently in the **Composer foundation phase**.
 
-The original 2016 implementation has been moved to the `legacy/` directory so it can be preserved as historical reference while the new library is built from scratch in future phases.
+This means the repository already has the initial Composer package structure, PSR-4 namespace configuration, base configuration classes, PHPUnit setup, PHPStan setup, PHP CS Fixer setup, and GitHub Actions workflow.
+
+The modern WebSocket runtime is not implemented yet.
+
+## Installation for development
+
+Clone the repository and install dependencies:
+
+```bash
+composer install
+```
+
+Validate the Composer package:
+
+```bash
+composer validate --strict
+```
+
+Run the test suite:
+
+```bash
+composer test
+```
+
+Run static analysis:
+
+```bash
+composer analyse
+```
+
+Check code style:
+
+```bash
+composer cs:check
+```
+
+Run all quality checks:
+
+```bash
+composer quality
+```
+
+Fix code style automatically:
+
+```bash
+composer cs:fix
+```
+
+## Requirements
+
+The modern version targets:
+
+- PHP 8.2 or higher.
+- `ext-sockets`.
+- `ext-json`.
+- Composer.
+
+Optional future features may require:
+
+- `ext-pdo` for SQL storage adapters.
+- Laravel packages for optional Laravel integration.
+
+## Namespace
+
+The modern library uses the following namespace:
+
+```txt
+Micilini\PhpSockets\
+```
+
+The current public entry point is:
+
+```php
+use Micilini\PhpSockets\WebSocket;
+
+echo WebSocket::version();
+```
+
+## Current structure
+
+```txt
+src/
+  WebSocket.php
+  Config/
+    ServerConfig.php
+    ChatConfig.php
+
+tests/
+  Unit/
+    SanityTest.php
+
+legacy/
+  EasyChat/
+  MediumChat/
+  README-2016.md
+  NOTES.md
+```
 
 ## Legacy code
 
-The original code is available here:
+The original 2016 implementation is preserved here:
 
 ```txt
 legacy/EasyChat
@@ -26,6 +122,8 @@ legacy/README-2016.md
 
 `MediumChat` contains the more advanced object-oriented version with callbacks and a better separation between the WebSocket server and the chat behavior.
 
+The legacy implementation is kept for historical and educational purposes only. The modern library will be implemented separately and should not depend on the old code structure.
+
 ## Why the legacy code was moved
 
 The old project was designed for PHP 5 and browser-based local testing. At that time, the server could be started by opening `server.php` in the browser or by running it manually.
@@ -53,16 +151,36 @@ The new implementation will be developed gradually and will include:
 - Laravel integration.
 - Tests, static analysis, and CI.
 
-## Roadmap
+## Roadmap phases
+
+The project is being implemented phase by phase:
+
+```txt
+Phase 00: Legacy preservation.
+Phase 01: Composer foundation, namespace, quality tools, and CI.
+Phase 02: WebSocket protocol core.
+Phase 03: Server runtime and events.
+Phase 04: Chat core and unique usernames.
+Phase 05: Modern EasyChat example.
+Phase 06: MediumChat example with callbacks.
+Phase 07: Private direct messaging.
+Phase 08: Private group rooms.
+Phase 09: Storage adapters and migrations.
+Phase 10: CLI runtime commands.
+Phase 11: Small attachments and emoji-safe payloads.
+Phase 12: Bot hooks and automation events.
+Phase 13: Laravel integration.
+Phase 14: Release documentation and Packagist preparation.
+```
 
-Implementation will follow the project roadmap phase by phase.
+## Production readiness
 
-The first phase preserves the legacy code and creates a clean baseline.
+This package is not production-ready yet.
 
-Future phases will introduce Composer, source code structure, WebSocket protocol handling, server runtime, chat features, examples, persistence, CLI tooling, and release documentation.
+The repository is currently being rebuilt. The modern WebSocket protocol, server runtime, chat system, examples, storage adapters, CLI commands, and Laravel integration will be added in future phases.
 
 ## Important note
 
-The legacy implementation is kept for historical and educational purposes.
+The goal is not only to restore an old chat demo.
 
-The new library will be implemented separately and should not depend on the old code structure.
+The goal is to transform PHPSockets With WebSockets into a modern, educational, extensible, native PHP realtime library.
diff --git a/composer.json b/composer.json
new file mode 100644
index 0000000..0dbc102
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,51 @@
+{
+  "name": "micilini/php-sockets-with-websockets",
+  "description": "Native PHP WebSocket and realtime chat library built from scratch. Works standalone or with Laravel.",
+  "type": "library",
+  "license": "MIT",
+  "keywords": [
+    "websocket",
+    "sockets",
+    "chat",
+    "realtime",
+    "php",
+    "laravel"
+  ],
+  "require": {
+    "php": "^8.2",
+    "ext-sockets": "*",
+    "ext-json": "*"
+  },
+  "require-dev": {
+    "phpunit/phpunit": "^10.0|^11.0",
+    "phpstan/phpstan": "^1.10|^2.0",
+    "friendsofphp/php-cs-fixer": "^3.0"
+  },
+  "suggest": {
+    "ext-pdo": "Required for SQL storage adapters and migrations.",
+    "illuminate/support": "Required for Laravel integration."
+  },
+  "autoload": {
+    "psr-4": {
+      "Micilini\\PhpSockets\\": "src/"
+    }
+  },
+  "autoload-dev": {
+    "psr-4": {
+      "Micilini\\PhpSockets\\Tests\\": "tests/"
+    }
+  },
+  "scripts": {
+    "test": "phpunit",
+    "analyse": "phpstan analyse src tests --memory-limit=512M",
+    "cs:check": "php-cs-fixer fix --dry-run --diff",
+    "cs:fix": "php-cs-fixer fix",
+    "quality": [
+      "@cs:check",
+      "@analyse",
+      "@test"
+    ]
+  },
+  "minimum-stability": "stable",
+  "prefer-stable": true
+}
\ No newline at end of file
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..4ba9d80
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,5 @@
+parameters:
+    level: 6
+    paths:
+        - src
+        - tests
\ No newline at end of file
diff --git a/phpunit.xml b/phpunit.xml
new file mode 100644
index 0000000..45a87ab
--- /dev/null
+++ b/phpunit.xml
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.5/phpunit.xsd"
+         bootstrap="vendor/autoload.php"
+         colors="true"
+         cacheDirectory=".phpunit.cache">
+    <testsuites>
+        <testsuite name="PHPSockets Test Suite">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
+    <source>
+        <include>
+            <directory>src</directory>
+        </include>
+    </source>
+</phpunit>
\ No newline at end of file
diff --git a/src/Config/ChatConfig.php b/src/Config/ChatConfig.php
new file mode 100644
index 0000000..2b774d6
--- /dev/null
+++ b/src/Config/ChatConfig.php
@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Micilini\PhpSockets\Config;
+
+use InvalidArgumentException;
+
+final readonly class ChatConfig
+{
+    public function __construct(
+        public int $maxDisplayNameLength,
+        public int $maxRoomNameLength,
+        public int $maxPrivateGroupMembers,
+        public bool $allowGuestSessions,
+        public int $historyLimit,
+    ) {
+        if ($this->maxDisplayNameLength < 1) {
+            throw new InvalidArgumentException('Maximum display name length must be greater than zero.');
+        }
+
+        if ($this->maxRoomNameLength < 1) {
+            throw new InvalidArgumentException('Maximum room name length must be greater than zero.');
+        }
+
+        if ($this->maxPrivateGroupMembers < 2) {
+            throw new InvalidArgumentException('Maximum private group members must be at least 2.');
+        }
+
+        if ($this->historyLimit < 0) {
+            throw new InvalidArgumentException('History limit cannot be negative.');
+        }
+    }
+
+    public static function new(
+        int $maxDisplayNameLength = 40,
+        int $maxRoomNameLength = 80,
+        int $maxPrivateGroupMembers = 20,
+        bool $allowGuestSessions = true,
+        int $historyLimit = 50,
+    ): self {
+        return new self(
+            maxDisplayNameLength: $maxDisplayNameLength,
+            maxRoomNameLength: $maxRoomNameLength,
+            maxPrivateGroupMembers: $maxPrivateGroupMembers,
+            allowGuestSessions: $allowGuestSessions,
+            historyLimit: $historyLimit,
+        );
+    }
+}
diff --git a/src/Config/ServerConfig.php b/src/Config/ServerConfig.php
new file mode 100644
index 0000000..574b5a8
--- /dev/null
+++ b/src/Config/ServerConfig.php
@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Micilini\PhpSockets\Config;
+
+use InvalidArgumentException;
+
+final readonly class ServerConfig
+{
+    public function __construct(
+        public string $host,
+        public int $port,
+        public int $maxPayloadBytes,
+        public int $tickMicroseconds,
+        public int $connectionLimit,
+        public bool $enableDebugLogs,
+    ) {
+        if ($this->host === '') {
+            throw new InvalidArgumentException('Server host cannot be empty.');
+        }
+
+        if ($this->port < 1 || $this->port > 65535) {
+            throw new InvalidArgumentException('Server port must be between 1 and 65535.');
+        }
+
+        if ($this->maxPayloadBytes < 1) {
+            throw new InvalidArgumentException('Maximum payload size must be greater than zero.');
+        }
+
+        if ($this->tickMicroseconds < 1) {
+            throw new InvalidArgumentException('Tick interval must be greater than zero.');
+        }
+
+        if ($this->connectionLimit < 1) {
+            throw new InvalidArgumentException('Connection limit must be greater than zero.');
+        }
+    }
+
+    public static function new(
+        string $host = '127.0.0.1',
+        int $port = 8080,
+        int $maxPayloadBytes = 65536,
+        int $tickMicroseconds = 10000,
+        int $connectionLimit = 100,
+        bool $enableDebugLogs = false,
+    ): self {
+        return new self(
+            host: $host,
+            port: $port,
+            maxPayloadBytes: $maxPayloadBytes,
+            tickMicroseconds: $tickMicroseconds,
+            connectionLimit: $connectionLimit,
+            enableDebugLogs: $enableDebugLogs,
+        );
+    }
+}
diff --git a/src/WebSocket.php b/src/WebSocket.php
new file mode 100644
index 0000000..70570c9
--- /dev/null
+++ b/src/WebSocket.php
@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Micilini\PhpSockets;
+
+final class WebSocket
+{
+    public static function version(): string
+    {
+        return '0.1.0-dev';
+    }
+}
diff --git a/tests/Unit/SanityTest.php b/tests/Unit/SanityTest.php
new file mode 100644
index 0000000..24fa667
--- /dev/null
+++ b/tests/Unit/SanityTest.php
@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Micilini\PhpSockets\Tests\Unit;
+
+use Micilini\PhpSockets\Config\ChatConfig;
+use Micilini\PhpSockets\Config\ServerConfig;
+use Micilini\PhpSockets\WebSocket;
+use PHPUnit\Framework\TestCase;
+
+final class SanityTest extends TestCase
+{
+    public function testVersionIsAvailable(): void
+    {
+        self::assertSame('0.1.0-dev', WebSocket::version());
+    }
+
+    public function testServerConfigDefaultsAreAvailable(): void
+    {
+        $config = ServerConfig::new();
+
+        self::assertSame('127.0.0.1', $config->host);
+        self::assertSame(8080, $config->port);
+        self::assertSame(65536, $config->maxPayloadBytes);
+        self::assertSame(10000, $config->tickMicroseconds);
+        self::assertSame(100, $config->connectionLimit);
+        self::assertFalse($config->enableDebugLogs);
+    }
+
+    public function testChatConfigDefaultsAreAvailable(): void
+    {
+        $config = ChatConfig::new();
+
+        self::assertSame(40, $config->maxDisplayNameLength);
+        self::assertSame(80, $config->maxRoomNameLength);
+        self::assertSame(20, $config->maxPrivateGroupMembers);
+        self::assertTrue($config->allowGuestSessions);
+        self::assertSame(50, $config->historyLimit);
+    }
+}