## Optional support & contact This book is shared freely. If you found it clarifying or useful, you're welcome (but never expected) to send a small Bitcoin or Lightning contribution. If you'd like to reach me directly, you can include your contact information in the payment note. This helps keep correspondence thoughtful and human-scale. {: .qr-code } `marcus_rydberg@strike.me` *Thank you for reading carefully.* --- ## License This work is licensed under a [Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License](https://creativecommons.org/licenses/by-nc-sa/4.0/). You are free to share and adapt this work with attribution, for non-commercial purposes, under the same license.