PHP Composer and Autoloading

Automate PHP dependency management and PSR-4 autoloading configuration.

187|20|Updated Nov 20, 2025

Search Tags:#php #composer #dependency-management #autoloading #psr-4

Ready to run

npx skills add https://github.com/TheBushidoCollective/han --skill php-composer-and-autoloading

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: PHP Composer and Autoloading
Source: https://github.com/TheBushidoCollective/han/tree/main/jutsu/jutsu-php/skills/php-composer-autoloading
Command: npx skills add https://github.com/TheBushidoCollective/han --skill php-composer-and-autoloading

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill covers Composer basics, dependency management, autoloading strategies, and modern PHP project organization.

Core Features & Use Cases

Composer Basics: Manage dependencies with composer.json and composer.lock.
PSR-4 Autoloading: Autoload classes based on namespace and directory structure.
Versioning & Scripts: Run tests and linters via composer scripts.

Quick Start

Initialize a PHP project with Composer and add a PSR-4 autoload rule for the App namespace.

Frequently Asked Questions about PHP Composer and Autoloading

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I manage PHP dependencies with Composer?▼

Composer automates PHP dependency management through a composer.json file that lists project requirements and version constraints. Running `composer install` downloads dependencies into a vendor directory and generates composer.lock to ensure reproducible builds across environments.

What is PSR-4 autoloading and how does it work in PHP?▼

PSR-4 autoloading automatically loads PHP classes based on namespace and directory structure without manual require statements. Composer maps namespace prefixes to directories in composer.json, allowing the autoloader to locate and instantiate classes on demand.

How do I set up PSR-4 autoload rules in my PHP project?▼

Define autoload mappings in the composer.json file by specifying namespace prefixes and their corresponding directory paths. After updating composer.json, run `composer dump-autoload` to regenerate the autoloader and enable class resolution.

Can I run tests and linters automatically with Composer?▼

Composer scripts allow you to define custom commands in composer.json that execute tests, linters, and other workflows. Run these scripts with `composer run [script-name]` to automate quality checks across development, testing, and production environments.

What's the difference between composer.json and composer.lock?▼

composer.json defines project dependencies with flexible version constraints, while composer.lock locks exact versions of all installed packages. composer.lock ensures every developer and deployment uses identical dependency versions for reproducible builds.

Do I need to commit composer.lock to version control?▼

Yes, committing composer.lock to version control ensures that all team members and production deployments install the exact same dependency versions, preventing unexpected behavior from version mismatches.