---
title: "Using PKI Express on PHP"
description: "Using PKI Express on PHP with the lacuna/pki-express Composer package (PHP 5.5+) and the available samples projects."
canonical: "https://docs.lacunasoftware.com/en-us/articles/pki-express/php"
locale: "en"
product: "PKI Express"
last_updated: "2026-10-12"
---

# Using PKI Express on PHP

This article describes how to use [PKI Express](https://docs.lacunasoftware.com/en-us/articles/pki-express) on PHP. To get started, choose one of the available samples' projects (organized by framework):

- [Plain](https://docs.lacunasoftware.com/en-us/articles/pki-express/php/plain)

## Composer Package

> **Note**
>
> This package only supports PHP *5.5+*.

To use PKI Express on PHP, you must include the composer package [lacuna/pki-express](https://packagist.org/packages/lacuna/pki-express), by adding the following line to your `composer.json` file:

```json
{
	"require": {
		"lacuna/pki-express": "^1.17.0"
	}
}
```

After that, execute the command `composer install`  to download the package and its dependencies (if you don't have Composer installed, get it [here](https://getcomposer.org/)).

This package is open-source, hosted on [GitHub](https://github.com/LacunaSoftware/PkiExpressPhp). Feel free to *fork* it if you need to make any customizations, and even submit a *pull request*.