---
title: "Deleting the Undeletable: Managing PII at Shopify - Shopify"
description: "Shopify describes how its Privacy and Data Science & Engineering teams redesigned analytical event handling to make personal-information deletion workable at Shopify’s scale. The effort addressed a lack of guaranteed event schemas by introducing a human-readable JSON schematization system covering field types, version evolution, ownership, data controllers and subjects, and privacy instructions; more than 4,500 active schemas now govern events. Before warehouse storage, identifying data is either obfuscated into generalized values, such as masked IP addresses with city or country information, or tokenized into consistent random values whose mappings reside in a secured vault and vary by controller and subject. Removing a vault mapping makes warehouse copies of the token non-detokenizable, allowing deletion without warehouse operations; the production platform processes about 20 billion events daily, while tens to hundreds of millions of mappings are deleted daily."
---

# Deleting the Undeletable: Managing PII at Shopify - Shopify

[Shopify](https://yomu.fyi/company/shopify) · 2023-10-18 · Jun 10, 2021

**Type:** Problem & solution

## Summary

Shopify describes how its Privacy and Data Science & Engineering teams redesigned analytical event handling to make personal-information deletion workable at Shopify’s scale. The effort addressed a lack of guaranteed event schemas by introducing a human-readable JSON schematization system covering field types, version evolution, ownership, data controllers and subjects, and privacy instructions; more than 4,500 active schemas now govern events. Before warehouse storage, identifying data is either obfuscated into generalized values, such as masked IP addresses with city or country information, or tokenized into consistent random values whose mappings reside in a secured vault and vary by controller and subject. Removing a vault mapping makes warehouse copies of the token non-detokenizable, allowing deletion without warehouse operations; the production platform processes about 20 billion events daily, while tens to hundreds of millions of mappings are deleted daily.

## Context

Shopify’s analytical events were collected at very large scale, but the lack of guaranteed schemas made it difficult to capture ownership and privacy context, handle personal information consistently, and effect deletion across data stored in the warehouse. Addressing the problem also involved adopting the system across teams and rebuilding historic datasets.

## Approach / What changed

The teams introduced a schematization platform with reviewed JSON schemas that define event structure, evolution, ownership, data subjects, controllers, and privacy handling. Identifying data is transformed before warehouse storage through irreversible obfuscation or tokenization. Token mappings are held in a secured vault, where deleting a mapping makes corresponding warehouse tokens non-detokenizable without operating on the warehouse.

## Takeaways

- Reviewed schemas capture field types, evolution, ownership, data subjects, controllers, and privacy handling, and enforce event structure at generation time.
- Obfuscation removes identifying details while preserving analytical value, whereas tokenization preserves consistent linkage and keeps the original PII-to-token mapping in a secured vault.
- Token deletion happens in the vault without a data-warehouse operation; the platform holds more than 500 billion mappings and deletes tens to hundreds of millions daily.

**Tags:** [Architecture](https://yomu.fyi/topic/architecture), [Data Pipelines](https://yomu.fyi/topic/data-pipelines), [Kafka](https://yomu.fyi/topic/kafka), [Privacy](https://yomu.fyi/topic/privacy), [Scalability](https://yomu.fyi/topic/scalability)

- Source: [Shopify](https://shopify.engineering/managing-pii-shopify-scale)
- Source URL: https://shopify.engineering/managing-pii-shopify-scale
- Ingested by Yomu: 2026-08-30T15:30:14.628Z

[Read original post](https://shopify.engineering/managing-pii-shopify-scale)