Trust & privacy

How your data flows

Tax data is sensitive. Here's the full, specific picture of what we store, who processes it, and when it's deleted. No marketing language, no unearned badges.

01

The flow, step by step

  1. 01

    You upload

    PDF, JPG, or PNG from your device

  2. 02

    Swiss storage

    Encrypted at rest, Supabase Zurich region

  3. 03

    Ephemeral sandbox

    An isolated virtual machine reads the file, then is destroyed

  4. 04

    Claude Agent (zero retention)

    Anthropic processes under ZDR — no logging, no training

  5. 05

    Your guide

    Structured entries appear in your session

  6. 06

    Deleted on finish

    All uploads + chat + guide erased when you archive the session

02

Sub-processors

Three parties touch your data, each with a specific role and retention policy.

  • Supabase

    Database + file storage, Zurich (Switzerland) region

    Deleted 24h after you finish your return

  • Anthropic (Claude Agent)

    Document extraction and guide assembly

    Zero data retention — no logging, no training

  • Vercel

    Web application hosting, Frankfurt region

    Standard request logs, no user content

03

Our commitments

  • Your files are stored in Switzerland and deleted within 24 hours of finishing your return
  • We never use your data to train AI models
  • You submit your return yourself in VSTax — we never touch your filing
  • Claude Agent operates under zero data retention for this app
  • You can export or delete your entire session at any time
  • We don't share data with tax authorities or any third party beyond our sub-processors (Supabase, Anthropic, Vercel)
04

Your data rights

Under Swiss and EU data protection law, you have the right to access, export, correct, and delete your data. Every active session has a privacy card showing exactly what's stored and how to remove it. For historical sessions or anything unclear, email privacy@calmtax.ch.

05

Contact

Security concerns, incident reports, or data requests: privacy@calmtax.ch