MarginGuard Data Processing Agreement

Last updated 13 September 2026. These terms apply to every merchant who installs MarginGuard and govern our processing of personal data on the merchant's behalf. A separately signed copy is available on request.

Parties and roles

The merchant operating the Shopify store is the controller and decides why the data is processed. Oleg Hasjanov, a sole trader established in Estonia, operating MarginGuard, is the processor and acts only on the merchant's instructions. Installing and configuring the app, including its rules and thresholds, constitutes those instructions. Contact: admin@shelfcompass.com.

Subject matter, duration and purpose

We process store data to calculate explainable discount-, return- and margin-dependency signals and to write those signals to the merchant's own Klaviyo account. Processing lasts while the app is installed. Local order history is kept for 18 calendar months, encrypted recovery backups expire after seven days, and uninstalling stops processing.

Categories of data and data subjects

Data subjects are the merchant's customers. We process customer email addresses, the Shopify customer identifier, order and refund amounts, dates, discount usage, the product variants bought with their quantities and net prices, and product-cost data. We do not process customer names, postal addresses, phone numbers, payment-card data, product titles or marketing-message content. Separately, a merchant's own contact email and message text are processed when the merchant submits support feedback.

Security measures

The application database and its recovery backups are encrypted at rest, and provider credentials are individually encrypted with separate keys. Transport uses HTTPS. Each store's data is tenant-isolated, authenticated access to customer-data screens is recorded with the acting account, and file access on the host is audited. Administrative accounts use unique credentials and multi-factor authentication where the provider supports it. Test and production data are kept separate.

Sub-processors

Hetzner Online GmbH hosts the application and its backups in Falkenstein, Germany (EU). Telegram Messenger receives support notifications, which contain only the topic, store domain, and the contact email and message text a merchant submits; do not include customer personal data in support messages. The merchant's own Shopify and Klaviyo accounts are the merchant's services, not our sub-processors. We will announce any new sub-processor on this page and by email before it receives data; a merchant who objects may uninstall the app, which ends the processing.

Assistance, data-subject requests and deletion

We handle Shopify's customers/data_request, customers/redact and shop/redact requests. Customer data requests are compiled into an export for delivery to the merchant; customer redaction deletes the matching local orders, refunds, scores, overrides and copies; shop redaction deletes the store and its dependent records. Non-readable keyed identifiers stop an old delivery from recreating erased data. Erased data can persist in encrypted backups until their seven-day expiry and is not reintroduced during recovery. On written request we delete or return the merchant's data instead of waiting for retention to expire.

Personal-data breach

We notify affected merchants without undue delay, and at the latest 72 hours after becoming aware of a personal-data breach, at the store's Shopify contact address, describing the data and stores involved and the steps taken. The merchant remains responsible for notifying its own customers and supervisory authority where required.

Confidentiality, audits and liability

MarginGuard is operated by one person, who is bound by these confidentiality obligations; there are no other staff with data access. On request we provide the information a merchant needs to demonstrate compliance and allow reasonable audit of this processing. We hold no third-party security certification and make no such claim. Estonian law and the GDPR apply.