Privacy Policy
This Privacy Policy explains how RangeFlux（運営: 数藤哲平） / RangeFlux (operated by Teppei Sudo) ("we", "us") handles personal data in connection with the RangeFlux website and applications (the "Service").
1. Information we collect
- Account data — your email address and its verified status, received from Google when you sign in, plus the account and session records needed to keep you signed in.
- Solve data — the solver configurations and ranges you save in the web app, the results computed for them, and results you choose to upload from the desktop app. They are stored on our servers so you can reopen them, and their count and size are recorded to manage your storage.
- Shared spots — if you create a share link for a solve, a share ID, the solve it points to, when it was created or revoked, a preview image of its root strategy, and a daily count of views. We do not record who views a share, apart from the technical logs below; a viewer's IP address is used only to limit request rates and is deleted within two days of their last request. If a viewer later creates an account, the share they came from is recorded as usage data.
- Usage records — the number of cloud solves you submit from the web app, counted per account and calendar month, kept to apply the limits of your plan.
- Study records — trainer questions served to you, summaries of your answers, a record of each decision you answer (the spot shown, your hand, the action you chose and its grade), your bookmarks, and your saved drills (their names and question settings).
- Purchase data — if you buy a Local Solver license, the email address, Stripe customer ID, and checkout session ID we receive from our payment processor, Stripe. Card numbers and other payment details are collected by Stripe; we neither receive nor store them.
- License & device data — a license key and per-device identifiers used to activate and verify the desktop app, where a Local Solver license has been issued to you.
- Usage data — linked to your account: when you submit a solve (its job ID and
whether it ran in the cloud or locally), when you first open a solve result, and the UTM parameters
(e.g.
utm_source) of the link that brought you to the web app. The desktop app sends usage data only if you opt in. - Feedback — the text you send with the in-app feedback form, together with your account ID and the context attached to it: the app version, OS name, current screen, the ID of the open solve, and the last error shown to you. Your email address is not attached.
- Error reports — when the app hits an error or a solve fails: the error type, message, and stack trace, the app version, and whether it runs on the web or the desktop app; for a failed solve, the job ID and the numeric solve settings. Reports may be sent while you are signed out. Reports are sent without your account or email address, though the job ID in a failed-solve report can be matched to the account that ran the solve; as with any request, the sender's IP address and request metadata are recorded in technical logs. The desktop app sends reports only if you opt in.
- Technical logs — standard server/access logs (e.g. IP address, request metadata) generated by our hosting provider for security and reliability.
2. How we use it
- To create and authenticate your account and keep you signed in.
- To run the solves you request and store their results for you.
- To publish the solves you choose to share, and to count how often shared links are viewed and lead to sign-ups, including which share a new account came from.
- To meter your cloud solves and apply the limits of your plan.
- To sell Local Solver licenses, issue and verify license keys, restore purchases, and handle refunds.
- To apply your storage limit and notify you before results over it are deleted.
- To provide trainer questions, history, bookmarks, and saved drills.
- To detect and fix bugs.
- To respond to the feedback you send and improve the Service.
- To understand where users drop off and which channels bring them, so we can prioritise improvements.
- To operate, secure, and improve the Service.
- To contact you about your account or important changes to the Service.
3. Service providers and international data transfers
When you create a share link, anyone with the link can view the solve's name and any description, board, ranges, bet and solver settings, solve statistics and dates, and the strategy at every node, without signing in. Your name and email address are not shown. This disclosure happens at your direction, and you can revoke the link at any time.
Apart from that, we share data only with processors that operate the Service on our behalf:
- Cloudflare — website and API hosting, the account, license, and solve databases, storage of solve results, cookie-less web traffic analytics (Cloudflare Web Analytics), and transactional email delivery (e.g. sign-in, license, or storage emails), and forwarding of mail sent to our support address, including the daily summary of feedback you send.
- Stripe — payment processing for Local Solver licenses.
- Google LLC — sign-in and web font delivery. When you sign in we receive your email address and its verified status from Google. Font files are loaded from Google's servers, which receive your IP address as part of the standard HTTP request. Our support mailbox is hosted on Gmail, so emails you send us and the daily summary of feedback are stored there.
- Google Cloud — execution of cloud solves (virtual machines in the Tokyo region receive your solve configuration and compute the result).
These providers may process data on servers located outside Japan, including the United States and the Asia-Pacific region. Where required by applicable law, we rely on appropriate safeguards such as standard contractual clauses. We do not sell your personal data.
4. Cookies and similar technologies
The web app sets a strictly necessary cookie to keep you signed in; the website uses only the strictly necessary cookies and similar technologies required by our hosting provider for security and content delivery. We do not use cookies for advertising, behavioral profiling, or third-party analytics. The desktop application does not use cookies.
The website stores a small amount of data in your browser's localStorage to remember your theme preference. It also keeps the UTM parameters of the link you arrived from in sessionStorage, and the web app keeps them in localStorage until they are sent as usage data (Section 1). The web app also stores your trainer data on your device in localStorage (answer summaries, decision records up to the latest 1,000 decisions, and saved drills) so the trainer works without an account; you can remove it by clearing your browser's site data. We use no other browser storage for tracking or analytics.
5. Where your data is processed
Solves you run in the web app are executed on our servers: the configuration you submit and the result computed for it are transmitted to us and stored in our database and object storage so that you can reopen them. See Section 9 for how long they are kept.
The desktop application performs its solver calculations locally on your computer. Range constructions, solver inputs, and solver outputs created there are processed and stored on your device. Only results you choose to upload, feedback you send, and error reports and usage data you have opted in to (Section 1) are transmitted to our servers; uploaded results are stored like web app solve data.
6. What we do not do
- We do not use your personal data, content, or solver inputs/outputs to train AI or machine-learning models.
- We do not subject you to automated decisions that produce significant legal effects on you. Automated checks may restrict license activation when abuse is suspected; these are operational controls and not decisions affecting your legal rights.
- We do not sell, rent, or trade your personal data.
7. Payments
Local Solver license payments are processed by Stripe. Card numbers and other payment details are collected directly by Stripe; we neither receive nor store them. Stripe handles them under its own privacy policy.
8. Security
Communication with the Service uses TLS encryption. Access to account, license, and solve records is limited to the operator under the principle of least privilege. No method of transmission or storage is fully secure; if a breach affecting your personal data occurs, we will notify you without undue delay where required by applicable law.
9. Retention and deletion
- Account records — retained while your account exists. They are deleted on request (see Section 10); sessions expire on their own.
- Solve configurations and results — retained while your account exists so you can reopen them, and deleted when you delete them, when your account is deleted, or on request. If a plan change or similar leaves you over your storage limit, we notify you and, after a 30-day grace period, delete the oldest results first. Uploads that never complete are deleted 24 hours after their last activity.
- Shared spots — a share stops being served when you revoke it or the solve is deleted (including deletion over your storage limit), and its preview image is deleted then. The share record (ID and dates) and its daily view counts are kept while your account exists and deleted with it. Cached copies may remain for up to a minute; link previews already generated by other services and copies made by viewers are outside our control.
- Usage records — retained as monthly counts while your account exists, and deleted when your account is deleted or on request.
- Study records — served questions are deleted after 90 days. Answer summaries and decision records created on the free plan are deleted after 90 days; on a paid plan they are deleted progressively once your current plan's retention period has passed (Study 30 days, Study Plus 90 days, Study Max 365 days). If you leave a paid plan, records created on it are deleted after a grace period we set. Bookmarks and saved drills are kept until you remove them or while your account exists.
- License, purchase, and email records — retained while your license is in use and for a reasonable period thereafter to handle support, accounting, and legal obligations. Records are deleted earlier on request (see Section 10).
- Server access logs — retained according to our hosting provider's standard retention period (typically a matter of days to weeks).
- Usage data — deleted after 180 days, and earlier when your account is deleted or on request.
- Feedback — retained while your account exists and deleted when your account is deleted or on request. The daily summary emailed to our support mailbox carries no account ID or email address and is kept with our support mail for as long as needed to handle it.
- Error reports — kept only in Cloudflare's logs and deleted automatically after at most 7 days.
- Transactional email logs — retained according to Cloudflare's standard retention period.
10. Your rights
You may contact us at any time to exercise the following rights:
- Access to the personal data we hold about you.
- Correction of inaccurate or incomplete data.
- Deletion of your data, including your account and the solves stored under it. Note: deletion will also invalidate any associated license key and we will be unable to re-issue it.
- Restriction of or objection to processing.
- A copy of your data in a portable, machine-readable form.
If you are located in the EU, UK, or another jurisdiction offering equivalent rights, you may also lodge a complaint with your local data-protection supervisory authority.
11. Age requirement
The Service is intended for users 18 years of age or older. We do not knowingly collect personal data from anyone under 18. If we become aware that we hold such data, we will delete the related account.
12. Contact
Questions or requests: support@rangeflux.com (operator: RangeFlux（運営: 数藤哲平） / RangeFlux (operated by Teppei Sudo)).
13. Changes
We may update this policy as the Service evolves. Material changes — such as new categories or items of data, new service providers, or new purposes of use — will be announced on this page and, where we have your registered email address, communicated by email. Minor or editorial changes will be reflected by an updated effective date on this page.