Privacy Policy

1. Controller

Roland Wenzlofsky Kantnergasse 53 1210 Wien Austria

Email: letters@dwhpro.com

We process personal data only for the following purposes and on the legal bases stated:

Purpose Legal basis Notes
Sending the free newsletter Art. 6(1)(a) GDPR (consent, double opt-in) We send content only after explicit confirmation of the email address. Consent can be withdrawn at any time via the unsubscribe link in any email or by emailing us.
Paid subscription ("Premium") Art. 6(1)(b) GDPR (performance of a contract) Processing of the data necessary for ordering, payment, and delivery.
Payment processing via Stripe Art. 6(1)(b) GDPR Transfer of the data needed to take payment to our payment service provider.
Security logs (web server, reverse proxy) Art. 6(1)(f) GDPR (legitimate interest) Detection and defence against attacks; abuse prevention. Retention of at most 14 days.
Backup of the platform Art. 6(1)(f) GDPR Recoverability after technical incidents. Encrypted storage.

3. Recipients / Processors

We use the following processors (Art. 28 GDPR). A data processing agreement is in place with each.

Provider Purpose Location of processing
Hetzner Online GmbH Server hosting Germany (Falkenstein/Nuremberg). EU.
Hetzner Online GmbH Encrypted backups (Storage Box) Finland or Germany. EU.
Cloudflare, Inc. DNS resolution (the dwhpro.com zone) USA — transfer based on EU Standard Contractual Clauses (SCC); Cloudflare also participates in the EU-US Data Privacy Framework (DPF).
Sinch Email Inc. (Mailgun) Sending newsletters and transactional emails EU region (api.eu.mailgun.net, processing in the Netherlands / Frankfurt). US parent — transfer based on SCC and DPF.
Stripe Payments Europe, Limited Payment processing for subscriptions Ireland (EU).
GitHub, Inc. Version control of the server configuration (no personal data of newsletter subscribers) USA — DPF.

4. Retention Periods

Data Retention
Free newsletter subscription until you unsubscribe
Paid subscription until termination of the contract; invoicing data retained for 7 years under § 132 BAO (Austrian tax law)
Web server logs 14 days maximum
Backups rolling: 7 daily, 4 weekly, 12 monthly

5. Your Rights as a Data Subject

You have the right at any time to:

  • Access the data stored about you (Art. 15 GDPR)
  • Rectification of inaccurate data (Art. 16 GDPR)
  • Erasure of your data (Art. 17 GDPR) — for example, by unsubscribing from the newsletter
  • Restriction of processing (Art. 18 GDPR)
  • Data portability in a structured, commonly used format (Art. 20 GDPR)
  • Object to the processing (Art. 21 GDPR)
  • Withdraw consent with effect for the future (Art. 7(3) GDPR)

To exercise these rights, an email to letters@dwhpro.com is sufficient.

6. Right to Lodge a Complaint

You have the right to lodge a complaint with the data protection authority:

Österreichische Datenschutzbehörde Barichgasse 40-42 1030 Wien https://www.dsb.gv.at

7. Cookies

This site uses only technically necessary cookies required for the operation of the membership functionality (login, session continuity). There is no web analytics, no tracking, and no integration of third-party advertising networks. Consent under § 165(3) TKG 2021 / ePrivacy is therefore not required.

If web analytics or third-party tracking is added later, a compliant opt-in cookie banner will be added and this notice updated.

8. Changes to This Notice

We reserve the right to amend this privacy notice in response to legal or technical changes. The current version is always available at this URL.


Last updated: 2026-05-05

Subscribe to DWHPro Letters

Practical field notes on enterprise data engineering, production AI systems, platform migration, and the senior engineering market.
Written by Roland Wenzlofsky Founder of DWHPro Author of Teradata Query Performance Tuning
Get the next issue
Subscribe