Shopify storefront for Sass aplication

Shopify Apps

Topic summary

A developer is exploring how to integrate Shopify with a custom SaaS application using a unified domain structure:

Desired Flow:

  • Landing page on Shopify for subscriptions/digital product purchases (my-sass-name.com)
  • Custom login page that authenticates users via the SaaS app’s API (my-sass-name.com/login)
  • Redirect authenticated subscribers to the SaaS application, ideally under the same domain (my-sass-name.com/sass)

Technical Considerations:

  • Webhook integration to notify the SaaS backend when users subscribe or purchase
  • Periodic user data synchronization between Shopify and the SaaS app
  • Alternative subdomain approach if same-domain routing isn’t feasible (app.my-sass-name.com)

Key Questions:

  1. Is building a custom app (available in the app store) a viable approach for this integration?
  2. Would this setup violate Shopify’s Terms & Conditions?

The discussion remains open with no responses yet.

Summarized with AI on November 3. AI used: claude-sonnet-4-5-20250929.
1

Hello,

I am researching possibilities to achieve such flow:

  1. Having landing page built via Shopify where end user can subscribe or buy digital products.

Domain example: (my-sass-name.com)

  1. Having a sign-in page to be part of sass-web-app, user would enter their email, submit the form (it would execute endpoint to my own sass web app.
    Domain example: (my-sass-name.com/login)

  2. Then, if user is subscribed or bought digital product, after they successfully logged (email, passwordless auth) in, they would be redirect to my sass web app.
    Domain example 1 (my-sass-name.com/sass) (if possible I would like to do redirect under same domain, just different path name).

Domain example 2 (app.my-sass-name.com) if example 1 wouldn’t be possible to achieve.

The main questions:

  1. Is it possible to achieve something like this by building custom app, that would be available in app-store?
  2. Would it be against shopify T&C ?

Any info would be appreciated.

UPDATE:

SO my vision would be something like this - when user becomes subscriber, or buys a digital product.
(There would be webhook that would notify sass-web app backend, so I could update user list).
Or if that’s not achievable - it would be possible to periodically fetch users to sync it with sass-web app db.