Terms of Use
License and usage terms for Versatile Sparks books and the interactive knowledge system.
Last updated: July 2026.
The books
Each book is sold as a DRM-free digital download (PDF + EPUB + source code). Your purchase grants you a personal, non-transferable license to read the book and to use the included source code in your own projects, including commercial projects.
You may not:
- Redistribute the book files or source code publicly.
- Resell, relicense, or bundle the book into a product you sell.
- Remove authorship or license notices from the source code.
Quoting short excerpts for review, teaching, or criticism is fine. If unsure, email yasaka.hanini@protonmail.com.
Updates
Books receive free rolling updates. When a new edition or revision is released, purchasers receive the updated files through Gumroad at no additional cost. The version you purchased remains licensed to you even if you do not update.
Refunds
If a book does not work for you, email us within 14 days of purchase for a full refund. We may ask what did not fit so we can improve it, but we will not withhold a refund.
The website
The interactive knowledge system on versatilesparks.pages.dev is provided as a free reference. It is licensed under CC BY-NC 4.0: you may share and adapt the concept and recipe text for non-commercial use with attribution. The source code shown inside recipes remains governed by the book license above.
No warranty
The books and website are engineering documentation, not legal or security advice. Browser automation against third-party sites may be governed by those sites' terms of service and by applicable law (e.g. CFAA, GDPR). You are responsible for how you use the techniques described. The material is provided "as is" without warranty of any kind.