Rillwork: Privacy Notice
DRAFT — not legal advice. Plain English, for the free beta. Have it reviewed before you publish it, and check it again against the live site and form before launch.
Last updated: 24 October 2026
Controller: Jake Cadwell, postal address to be added (PO box being set up). Contact: hello@rillwork.com.
The short version
- Your models never leave your computer. The app runs in your browser. Nothing is uploaded, and no server of ours touches your models or results.
- The sign-up form collects your email and your survey answers. We use them to run the beta and to decide what to build.
- Optional online features contact third parties only when you turn them on.
- No ads. We do not sell your data, and the website and app have no advertising trackers.
1. Your models and results
- When you open an
.inpfile, the app reads it inside your browser. - The EPA SWMM engine runs in your browser tab, on your own processor.
- Reports and saved files are written on your device.
We never receive your model files, data files, results or reports. We cannot see them and cannot recover them.
The app may keep settings or a working copy in your browser's local storage on your own device, so that your work survives a page reload. Clearing your browser's site data removes them.
2. The beta sign-up form
The sign-up form is part of our own landing page. It collects:
- your email address (required);
- your answers to the survey: your type of work, whether you've tried the beta, the tools you use now, your typical model size, your view of the planned price, what has to work on day one, and any beta problems you choose to describe (the free-text answers are optional);
- your consent to beta emails (a required checkbox).
Where your answers are stored. When you press the button, the page sends your answers to our own sign-up service, which stores them in our own database at Cloudflare (Cloudflare D1). Cloudflare runs that service and database for us as our processor; we decide what is stored and why.
Bot protection. The form uses Cloudflare Turnstile to block automated sign-ups. Its check loads when you reach the form. Turnstile processes technical data such as your IP address and signals from your browser and device, to tell people from bots. Cloudflare's Turnstile privacy addendum explains how: https://www.cloudflare.com/turnstile-privacy-policy/
Your IP address. Our sign-up service uses your IP address briefly, to limit how many sign-ups can come from one address. We do not store it: the limit uses a scrambled (keyed hash) form of it that is kept only for the current time window.
No other company receives your answers through the form. (An earlier plan used the form service Tally; Tally is no longer involved.)
We use this information to:
- send beta updates;
- invite you to give feedback or to become a design partner;
- tell you when paid licences start;
- understand what engineers need.
Legal basis, where one is needed: your consent (the checkbox), and our legitimate interest in improving the product. Survey answers are reported only in aggregate. Anything we publish about the results never names you.
3. Optional online features (off until you turn them on)
The app works offline. These features make network requests only after you switch them on:
| Feature | Who it contacts | What they receive |
|---|---|---|
| NOAA rainfall lookup | US National Oceanic and Atmospheric Administration, Precipitation Frequency Data Server | The latitude and longitude you ask about, plus your IP address and browser details, as with any web request |
| Map background | OpenFreeMap tile servers | The map area and zoom level being viewed, plus your IP address and browser details |
Neither request includes your model file. Each provider handles the data under its own terms. Turn a feature off and those requests stop.
4. Website hosting
The website and app files are served by Cloudflare Pages. Like any web host, it may log technical data such as IP addresses, requested pages and browser type, for security and operations, under its own privacy policy.
The website and app load no analytics, tracking or advertising scripts, and set no analytics or advertising cookies. If that ever changes, we will update this notice before turning anything on.
5. Email
We send beta emails from hello@rillwork.com through Cloudflare Email Sending. Every email has an unsubscribe link. You can also reply "unsubscribe" or write to hello@rillwork.com.
6. Files you choose to send us
If you email us a sample model or a bug report:
- we use it only to fix and test Rillwork;
- we keep it only as long as that needs;
- we never share it outside the people working on Rillwork, and never publish it, without your written permission.
Remove client-confidential data first, or ask us before sending.
7. How long we keep data
- Beta-list data: until you unsubscribe or ask us to delete it, or 12 months after the beta ends, whichever comes first.
- Sample files: deleted when the related issue is closed, unless you agree otherwise.
8. Your rights
You can ask us to show, correct, export or delete your data, or to stop emailing you: write to hello@rillwork.com. Depending on where you live (for example the EU, the UK or California), you may have further rights, including complaining to your data-protection authority.
9. Children
Rillwork is a professional tool and is not aimed at children under 16.
10. Payments (after the beta, not now)
The beta takes no payments. If paid licences start (planned at $490 per user per year), a payment provider will handle card details, and we will update this notice before taking any payment. We will not see your full card number.
11. Changes
We will update the date above when this notice changes, and email the beta list about significant changes.