Terms of service

Last updated 9 October 2026

Stacklens is a Shopify app operated by Blackout Media, a company established in Brazil ("we"). These terms apply to the store that installs it ("you"). Installing or using the app means you accept them. Your use of Shopify itself stays under your agreement with Shopify.

What the app does

Stacklens reads your discounts and products from Shopify and shows how the discounts combine: which pairs stack, which clash, which are silently left out, which reach products you never discount, and which settings may need a look. It can send alerts to Slack.

It does not change your store. The app has read-only access. Fixes are made by you, in Shopify's own discount pages.

Estimates

The matrix and the cart simulator follow each discount's settings and Shopify's published combination rules. They are estimates, not checkout results. Shopify decides what a cart gets at checkout, and discounts created by other apps are shown as unknown. Test a real checkout before a launch.

Price

Stacklens is free. If we introduce paid plans, we will say so in the app before anything is charged, any charge will go through Shopify's billing, and you will have to approve it there.

Your data

The settings you enter are yours. You give us permission to store and process them, and what the app reads from your store, to run the app for you, and for nothing else. What we collect and how long we keep it is in the privacy policy.

What you are responsible for

• Your discounts and the decisions you make from the app's findings.
• Who has access to your Shopify admin, and so to the app.
• The Slack webhook you give for alerts.
• Using the app lawfully, and not trying to disrupt it or reach another store's data.

Availability and changes

We work to keep the app available and correct, but we do not promise that it will be uninterrupted or free of errors. We may change, add or remove features.

Ending

You can stop at any time by uninstalling the app from your Shopify admin; your data is then deleted as the privacy policy describes. We may suspend a store that breaks these terms.

No warranty

The app is provided as it is, without warranties of any kind, to the extent the law allows.

Liability

To the extent the law allows, we are not liable for lost profits, lost data or indirect losses arising from the use of the app, and our total liability to you is limited to what you paid us for the app in the twelve months before the claim.

Law

These terms are governed by the laws of Brazil.

Changes to these terms

When these terms change, the date at the top changes with it. Questions: support@merchantsuite.io.