Privacy policy

Last updated 9 October 2026

Stacklens is a Shopify app operated by Blackout Media, a company established in Brazil. It shows how a store's discounts combine and conflict. This page says what the app and this website collect, why, for how long, and where it is processed.

Stacklens does not read or store anything about a store's customers or orders. It has no permission to: the app asks Shopify only for read access to discounts and to products.

What the app reads from a store

• The store's myshopify.com address and its currency.
• Each discount: its Shopify id, title, codes (up to three per discount, and how many it has), type, class, status, start and end dates, usage limit and how many times it has been used, minimum requirement, value, and its "combines with" settings.
• Whether a discount is limited to some customers. The app records only that it is limited; it does not read which customers or segments.
• Which products each discount reaches, as Shopify product ids, including the products in collections a discount targets.
• The ids and titles of products carrying the never-discount tag the merchant chooses.

The app stores the access token Shopify issues for the store, which lets it read discounts and products. It never writes to the store.

What the app works out and keeps

• Its findings: pairs of discounts that clash, stack or are silently excluded, discounts that reach never-discount products, and settings to review, each with the date it was first and last seen.
• A daily count of how many times each discount has been used, to spot a code used much faster than before.
• The totals of each scan, for the chart of conflicts over time, and a log of the alerts sent.

What a merchant enters

• The never-discount tag and the deep stack limit.
• A Slack incoming webhook URL for alerts. It is shown back only in part.

The app does not store the names, email addresses or passwords of the people who use it. Signing in is handled by Shopify.

How it is used

To show the store's discounts and how they combine, and to send the alerts the merchant turns on. Nothing is sold, shared for advertising or used to train models.

Where it is processed

• Cloudflare runs the app and serves this website. Its logs record requests to the app, including the store's address, for a short time.
• Neon hosts the database, on Amazon Web Services in the United States (Ohio).
• Shopify, whose admin the app runs inside.
• Slack, when the merchant connects a Slack webhook: alert messages are sent to it.

How long it is kept

For as long as the app is installed. When a store uninstalls Stacklens, its access token is deleted at once. Shopify then asks the app to erase the store's data 48 hours after the uninstall, and the app deletes everything it holds for that store: its settings, its discounts as last read, the findings, the usage history, the scan history and the alert log. A store that reinstalls within those 48 hours finds its settings as it left them.

This website

This website sets no cookies and runs no analytics or advertising scripts. Cloudflare, which serves it, processes the IP address of each request.

Requests and questions

To see, correct or delete what Stacklens holds for your store, or to ask anything about this policy, write to support@merchantsuite.io from an address that belongs to the store. A buyer who wants their data from a store should ask the store: Stacklens holds none of it.

When this policy changes, the date at the top changes with it.