Company & subprocessors
Last updated: 5 October 2026
Company information
Whyston is operated by:
Vitero Corp s.r.o.
Primátorská 296/38, 180 00 Prague 8, Czech Republic
Company registration no. (IČO): 10675400
VAT ID (DIČ): CZ10675400
General enquiries and support: support@whyston.com
Privacy and data protection: privacy@whyston.com
Legal: legal@whyston.com
Subprocessors
These companies process customer data on our behalf to provide Whyston. Each is bound by a data processing agreement, and transfers outside the EU/EEA rely on the European Commission's Standard Contractual Clauses. AI providers process content under API terms that exclude training on it. We announce changes to this list on this page.
| Subprocessor | Purpose | Location |
|---|---|---|
| Supabase | Authentication, database and file storage | EU (Ireland) |
| Vercel | Application hosting and serverless functions | EU (Dublin) functions; global edge network |
| OpenAI | Deck generation, assistant and web research (API, no training) | United States |
| Google (Gemini / Vertex AI) | Reading and extracting uploaded sources (API, no training) | EU (Vertex, europe-west1) and United States |
| Anthropic | AI model provider (API, no training) | United States |
| fal.ai | AI image generation, only when requested | United States |
| Polar | Payments, subscriptions and invoicing (merchant of record) | United States |
| Resend | Transactional email | United States |
| PostHog | Product analytics (consent-based) | EU (Frankfurt) |
| Sentry | Error monitoring | EU (Germany) |
| Better Stack | Uptime monitoring and status page (no customer content) | EU |
| Microsoft | Sign-in for the PowerPoint add-in | Global |
Data processing agreement
Business customers can sign a data processing agreement (DPA) with Vitero Corp s.r.o. before a pilot or subscription starts. Write to legal@whyston.com.