How to Install Composer with PHP

by Blog Admin
August 26, 2025
24

Composer is the standard tool for managing PHP dependencies. It automates library installation, enforces version constraints, and helps organize autoloading, making it an essential part of modern PHP development. Whether you’re building with frameworks like Laravel, Symfony, or Slim, Composer ensures consistency across environments and simplifies dependency resolution.

This article explains how to install Composer with a specific PHP version on a Linux system. This setup is useful when working across multiple PHP projects or servers that require different runtime versions. You’ll learn how to install Composer safely, bind it to a specific PHP version such as PHP 8.4, and create reusable aliases for scripting or interactive use.

Prerequisites

Before you begin, ensure you have:

Access to a Linux instance.
SSH access to the server.
A non-root user with sudo privileges.
Updated the server.

Install PHP

Install PHP, the command-line interface (CLI), and required tools such as curl and unzip using your distribution’s package manager.

Install PHP on Ubuntu and Debian

Run the following command to install the default PHP version and required utilities on APT-based systems.

console

$ sudo apt install -y php php-cli curl unzip

To install a specific PHP version (such as 8.3 or 8.4), add a third-party repository:

On Ubuntu, use the Ondřej Surý PPA.
On Debian, use the SURY repository.

These repositories provide maintained versions of PHP not available in the default APT sources.

Install PHP on Rocky Linux and AlmaLinux

On DNF-based distributions, install PHP and required tools with:

console

$ sudo dnf install -y php php-cli curl unzip

To install a specific PHP version, enable the EPEL and Remi repositories. These repositories offer multiple PHP versions for RHEL-based systems including Rocky Linux and AlmaLinux.

Install Composer Using a Specific PHP Version

Note

This article uses PHP 8.4 as the example version. On DNF-based distributions (like Rocky Linux or AlmaLinux), the system uses php as the command unless update-alternatives is configured. If php8.4 doesn’t work, use php instead.

Follow these steps to install Composer using PHP 8.4.

Download the Composer installer using PHP 8.4.

console

$ php8.4 -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"

Get the installer signature. This ensures the installer is authentic and has not been tampered with.
console
```
$ curl -s https://composer.github.io/installer.sig
```
Copy the hash from the output. You’ll need it for verification in the next step.

Verify the installer. Replace your_hash_here with the hash you copied:

console

$ php8.4 -r "if (hash_file('sha384', 'composer-setup.php') === 'your_hash_here') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"

Output.

Installer verified

Run the Composer installer using PHP 8.4 and install it system-wide.

console

$ sudo php8.4 composer-setup.php --install-dir=/usr/local/bin --filename=composer

Output.

All settings correct for using Composer
Downloading…

Composer (version 2.8.8) successfully installed to: /usr/local/bin/composer
Use it: php /usr/local/bin/composer

Clean up the installer file.
console
```
$ rm composer-setup.php
```

Verify the Composer installation.

console

$ composer

Output.

    ______
   / ____/___  ____ ___  ____  ____  ________  _____
  / /    / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
 / /___/ /_/ / / / / / / /_/ / /_/ (__  )  __/ /
 \____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
                     /_/
Composer version 2.8.8 2025-04-04 16:56:46

Run Composer with a Specific PHP Version

To run Composer with a specific PHP version (like PHP 8.4), follow these steps to configure your environment.

Confirm the path of the PHP 8.4 binary.
console
```
$ which php8.4
```
Output.
```
/usr/bin/php8.4
```
Run Composer using the PHP 8.4 binary.
console
```
$ php8.4 /usr/local/bin/composer
```
Create an alias so composer always runs with PHP 8.4. (Optional)
console
```
$ echo 'alias composer="php8.4 /usr/local/bin/composer"' >> ~/.bashrc
```
For portability in scripts or cron jobs, consider using a shebang like #!/usr/bin/env php instead of hardcoding a version path.
Reload your shell configuration to apply the alias.
console
```
$ source ~/.bashrc
```
If you’re using the Zsh, replace ~/.bashrc with ~/.zshrc.

Verify that Composer now runs with PHP 8.4.

console

$ composer --version

Output.

Composer version 2.8.8 2025-04-04 16:56:46
PHP version 8.4.0 (/usr/bin/php8.4)
Run the "diagnose" command to get more detailed diagnostics output.

For managing multiple Composer versions or isolating global dependencies per PHP version, consider tools like cgr, composer-bin, or asdf.

Test Composer Functionally (Optional)

To confirm that Composer is functional and can generate project scaffolding:

Run composer init in non-interactive mode to generate a minimal composer.json.

console

$ composer init --name=test/app --description="Test app" --author="Your Name" --require=php:^8.4 --no-interaction

View the generated file to confirm success.

console

$ cat composer.json

Output.

{
    "name": "test/app",
    "description": "Test app",
    "require": {
        "php": "^8.4"
    }
}

You can now run composer install or add additional dependencies to begin building your PHP project.

Conclusion

In this article, you installed Composer on a Linux system and configured it to run with a specific PHP version such as PHP 8.4. You learned how to safely verify the installer, install Composer system-wide, and run it using the correct PHP binary. You also created a reusable alias for convenience and confirmed that Composer works by initializing a basic project.

With this setup, you’re now equipped to manage dependencies across multiple PHP projects with varying version requirements.

How to Install Composer with PHP Composer is the standard tool for managing PHP dependencies. It automates library installation, enforces version constraints, and helps organize autoloading, making it an essential part of modern PHP development. Whether you’re building with frameworks like Laravel, Symfony, or Slim, Composer ensures consistency across environments…

How to Install Composer with PHP Composer is the standard tool for managing PHP dependencies. It automates library installation, enforces version constraints, and helps organize autoloading, making it an essential part of modern PHP development. Whether you’re building with frameworks like Laravel, Symfony, or Slim, Composer ensures consistency across environments…

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