Sub-Processors
Last updated: 6 June 2026
This page lists the third-party service providers that Class Diagnostix Ltd uses, or expects to use, to provide, host, secure, support and administer the Class Diagnostix service.
For school-uploaded pupil and assessment data, schools and trusts are usually the data controller and Class Diagnostix Ltd is usually the data processor. Where a third-party provider processes that data for us, that provider is treated as a sub-processor.
This list should be reviewed before publication and whenever a material supplier is added or replaced.
Current / Expected Production Sub-Processors
| Provider | Purpose | Personal data involved | Location / transfer notes | Status |
|---|---|---|---|---|
| Railway Corp. | Application hosting, infrastructure, persistent storage, PostgreSQL database and Redis task queue/cache services. | Account data, school-uploaded assessment data, generated reports, files, logs and technical metadata. | Confirm the configured production region before publication. If data is processed outside the UK, appropriate UK GDPR transfer safeguards should apply. | Expected production infrastructure. Confirm before publication. |
| Email / mailbox provider | Business email, support enquiries, customer communications and contract administration. | Names, email addresses, school/organisation details, message content and attachments sent to us. | Confirm actual email provider and processing locations before publication. | Replace this row with the actual provider before publication. |
| Backup provider | Production backup storage and restoration support, once the backup service is implemented. | Backup copies of production app data, which may include account data, school-uploaded assessment data and generated reports. | Confirm actual backup provider, region and retention configuration before publication. | Planned. Add the actual provider when implemented. |
Services Not Currently Used For Production App Data
| Service type | Current position |
|---|---|
| External PDF or rendering services | Not currently used. PDF/report rendering is carried out by Class Diagnostix using server-side application code, local Python PDF libraries and local Playwright/Chromium rendering within the app hosting environment. |
| AI or automated content-generation APIs | Not currently used for processing school-uploaded pupil assessment data. |
| Analytics providers | Not currently listed as production sub-processors. If analytics are added, they should be consent-controlled where required and added to this page before use. |
| Payment processors | Not currently listed as production sub-processors. If online card or subscription payments are added, the payment provider should be added to this page before use. |
How We Manage Sub-Processors
We aim to use service providers that offer appropriate security, confidentiality and data protection commitments. Where a provider processes personal data for us as a processor or sub-processor, we will put appropriate contractual protections in place.
We remain responsible to our customers for the performance of our sub-processors where required by our Data Processing Agreement and applicable data protection law.
We will update this page when we add or replace a material sub-processor. Customers who need direct notice of material sub-processor changes should contact us so this can be agreed in the relevant order form or Data Processing Agreement.
Contact
Questions about sub-processors should be sent to hello@classdiagnostix.com.