Authenticate Shopify App with custom distribution for multiple clients

Hello everyone,

I’ve created a Shopify App out of the remix template and now have some problems implementing it to multiple clients. I’m using the custom districution method which means I have to create separate Apps in the partners dashboard and then let customers install the app. This works perfectly fine.
The problem now is that I need a better workflow when deploying the app. For example the app is deployed on one specific hoster where the envs are set. Now every customer has a different “SHOPIFY_API_KEY” and “SHOPIFY_API_SECRET”. How can i dynamically assign these based on which customer is accessing the the app?

In the remix template it happens at this specific point:

const shopify = shopifyApp({
  apiKey: process.env.SHOPIFY_API_KEY,
  apiSecretKey: process.env.SHOPIFY_API_SECRET || "",
.....

Right now the only solution I know is to deploy the app for each customer separately and then insert the deployment link for each customer. This is much work an I would prefer to have just one deployment and one link. How is this possible? I wasn’t able to find a good solution so far.

Best regards
Lukas