---
title: "Introduction"
description: "Lightweight kernel with a dependency injection container, inspired by Symfony, with .env files and a container cache"
type: "docs"
category: "doc"
tags: []
authors: [Anonymous]
date: "2026-10-10"
last_update: "2026-10-10"
time_minutes: 2
draft: false
unlisted: false
url: "https://www.derafu.dev/docs/core/kernel/introduction"
---

# Lightweight Kernel Implementation with DI Container

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A lightweight kernel implementation with a dependency injection container, inspired by Symfony but with a minimal approach.

## Overview

Derafu Kernel provides a clean, flexible foundation for PHP applications with minimal dependencies. It offers:

- A lightweight kernel implementation with DI container.
- Environment-aware configuration management.
- Support for PHP and YAML configuration files.
- Container caching for improved performance.
- Built-in support for multiple environments (dev, prod, test, etc.).

## Installation

```bash
composer require derafu/kernel
```

## Basic Usage

### Create a Kernel

The simplest way to use the kernel is to create an instance with a specific environment:

```php
use Derafu\Kernel\MicroKernel;

// Create a kernel with 'dev' environment and debug mode enabled.
$kernel = new MicroKernel('dev', true);

// Boot the kernel to initialize the container.
$kernel->boot();
```

### Custom Kernel Implementation

You can extend the `MicroKernel` class to customize its behavior:

```php
use Derafu\Kernel\MicroKernel;
use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;

class AppKernel extends MicroKernel
{
    // Override the default configuration files.
    protected const CONFIG_FILES = [
        'services.php' => 'php',
        'routes.php' => 'routes',
        'parameters.yaml' => 'yaml',
    ];

    // Add additional container configuration.
    protected function configure(ContainerConfigurator $configurator): void
    {
        $services = $configurator->services();

        // Register application services.
        $services->set('app.service', MyService::class)
            ->public()
            ->args(['param1', 'param2']);
    }
}
```

### Environment Configuration

The kernel uses an environment object to determine settings and directories:

```php
use Derafu\Kernel\Environment;

// Create an environment with custom settings.
$environment = new Environment(
    'prod',                 // Environment name.
    false,                  // Debug mode.
    ['custom' => 'value']   // Context variables.
);

// Create a kernel with the custom environment.
$kernel = new MicroKernel($environment);
```



---
Last updated on 10/10/2026