---
title: "Subprocessors | Once Books"
description: "The third parties that help run Once Books and what data each receives — the processors active today, and those being onboarded next."
source: "https://www.oncebooks.com/subprocessors/"
---

Legal

# Subprocessors

Effective 18 August 2026

These are the third parties that process data on our behalf to run Once Books. We give **30 days’ notice** before adding or replacing one. This list reflects what is actually enabled today; the sensitive tiers below are named as they’re engaged, before any real photo is processed.

## Active today

| Provider | Purpose | Data received | Location |
| --- | --- | --- | --- |
| BuildBase | Accounts, workspaces, billing and credits | Email, name, workspace membership, and subscription/payment metadata. Never photos or book images. | United States |
| Stripe (via BuildBase) | Payment processing | Billing details and card data, handled on Stripe’s systems — we never see card numbers. | United States / EU |
| Vercel | Website and application hosting, content delivery | Requests to the site and app. The marketing site is static and carries no personal data. | United States |

A boundary worth stating: our accounts and billing provider **never receives a photograph or a generated image** — the platform has no file API at all. That’s architectural, not a policy we hope holds.

## Being onboarded

Not yet enabled. Each provider is named here once it is under a signed agreement — for the tiers that touch a child’s likeness, one that prohibits training on your content.

**AI image & text generation**

These receive a child’s reference images and story text to generate pages. Each will be listed here by name once it is under a signed agreement that prohibits training on your content — and our system refuses, in code, to send identity references to any provider that trains on user data.

**Safety moderation**

Scanning uploads and generated images for harmful content, including child-safety hash-matching. We are selecting vendors with an explicit child-protection mandate; each will be named here once engaged.

**Product analytics & diagnostics**

Privacy-preserving usage metrics and error monitoring, off by default and never carrying your photos or book content. Named here if and when enabled.

Questions, or to be notified of changes: [privacy@oncebooks.com](mailto:privacy@oncebooks.com). How data is handled overall is in the [Privacy Policy](https://www.oncebooks.com/privacy/).