1. Who we are
Slux (slux.app) is an online service with interactive college math lessons. It is run by the Slux team, based in Kazakhstan ("we", "us"). You can reach us at support@slux.app.
2. Who can use it
Slux is for people who are 18 or older. By using it or creating an account you confirm that you are at least 18. The courses are at college level (first- and second-year university mathematics).
3. Accounts
You can start without an account: when you take the quiz or open a lesson, we create a guest profile tied to your browser so your progress is saved. You can turn it into an account with your email (or Google) at any time, and everything you did as a guest moves into it. Keep your password to yourself; you are responsible for what happens under your account. One account is for one person.
4. Free access and paid plans
- Free: the first unit of the course you pick, with no card needed.
- Lifetime ($5, first 500 buyers): a single payment that opens every course and lesson, including lessons added later, for as long as Slux runs. It does not renew. The offer closes once 500 lifetime purchases are paid; a refunded purchase frees its place.
- Monthly ($11.99): every course and lesson. The subscription renews automatically each month until you cancel.
Prices are shown on the pricing page before you pay. Taxes may be added at checkout depending on where you live.
5. Payments
Payments are processed by Polar (polar.sh), which acts as our merchant of record: Polar sells the plan to you, charges your card, handles taxes and sends receipts. Polar's buyer terms apply to the payment itself. We never see or store your card number.
6. Cancelling
You can cancel a subscription at any time from your profile (Me, then Manage billing) or by writing to us. You keep access until the end of the period you already paid for; after that the account goes back to the free plan and your progress stays.
7. Refunds
See the Refund Policy. Nothing in these terms limits refund rights you have under the law of your country.
8. Using the service fairly
- Use Slux for your own learning. Don't copy, scrape, resell or republish lessons, problems or art from the site.
- Don't share an account, try to break into other accounts or the service, or overload it with automated requests.
- Don't use the lessons to cheat on graded work. Follow your school's rules on outside help.
9. What it is and isn't
Slux is a learning tool. It is not a university or college, it does not grant degrees or credits, and it is not affiliated with any university, testing organization or the institutions whose open courses inspired some of our syllabi (including MIT). We work hard to make the lessons correct and useful, but we can't promise any grade or exam result.
10. Content and ownership
The lessons, interactive problems, text and code are ours. Classical artworks on the site are in the public domain; Aristotle is a character inspired by the philosopher. You may keep notes and screenshots for your own study.
11. Changes and availability
We improve Slux all the time and may change, add or remove features and lessons. If a change materially reduces what a paid plan includes, we will tell you in advance and you may cancel. The service may occasionally be unavailable for maintenance or reasons outside our control.
12. Ending your use
You can delete your account at any time on your profile page. We may suspend or close accounts that break these terms, after a warning where reasonable; if we close a paid account without a breach on your side, we refund the unused part of the period.
13. Liability
The service is provided "as is". To the extent the law allows, we are not liable for indirect or consequential losses, and our total liability for any claim is limited to the amount you paid us in the 12 months before it. Nothing here excludes liability that cannot be excluded by law.
14. Law and changes to these terms
These terms are governed by the laws of Kazakhstan, without affecting mandatory consumer protections of the country where you live. We may update these terms; if a change is material we will tell you on the site or by email before it applies. Continuing to use Slux after that means you accept the new terms.