Secure Heroku Server Deployment for API

I'm in need of an expert developer with a keen understanding of PHP, Heroku, and Shopify. This project entails the deployment of a Heroku server where my API key will be secure and stored in an environment variable. You'll also need to utilize this Heroku-based API key on my Shopify platform to access and display user data through API calls.

Ideal Skillset and Experience Required:
- Proficiency in PHP
- Expertise in deploying and managing Heroku servers
- Understands how to secure API keys on Heroku
- Experience with Shopify API integration and displaying data.