Privacy Policy
Last updated: October 30, 2026
1. Who we are
This policy explains what personal information Mastering SWE LLC ("Mastering SWE," "we," "us") collects when you use masteringswe.com and our community spaces, how we use it, and the choices you have.
We are the controller of your personal information. Questions go to rawswe@masteringswe.com. We do not sell your personal information.
2. Information we collect
We collect only what we need to run the study app, bill subscriptions and support you.
| Category | What it includes | Where it comes from |
|---|---|---|
| Account | Email address, password if you set one (stored hashed, never in plain text), account creation date, and when you accepted our Terms and which versions. If you sign in with Google or GitHub: your name, profile picture, account ID with that provider and the sign-in tokens it issues | You, at sign-up; Google or GitHub, if you sign in with them |
| Study activity | Cards you unlock, your recall ratings, review schedule and progress, the code you write on coding cards, and your study settings for each deck | Your use of the app |
| Billing | Plan, subscription status, renewal date, and our payment processor's customer and subscription IDs for you | Our payment processor |
| Support and feedback | Messages you send us | You |
| Community | Your Discord account ID, if you connect Discord; your Discord username, avatar and messages in our server, recent ones of which are shown to subscribers on the site's Community tab; name and anything you share on group calls, which run on Zoom | You, Discord and Zoom |
| Device and usage | IP address (used to limit repeated sign-in and sign-up attempts), request timestamps, error logs | Automatically, via our servers |
We do not collect your card details or billing address; our payment processor collects them on its checkout page and uses your billing address to calculate sales tax. We do not ask for sensitive information such as health, race or government ID numbers, and please do not share it in the community.
3. How we use information
- Run the Service: create and secure your account, track your unlocks, and schedule card reviews with spaced repetition.
- Process payments: start, renew and cancel subscriptions, and handle billing questions.
- Communicate with you: send an email to confirm your address when you sign up, have our payment processor send receipts and billing notices, and reply to support requests.
- Improve the Service: diagnose and fix errors using our server logs.
- Run the community: add your connected Discord account to our subscriber-only server and remove it when your subscription ends, show recent server messages on the Community tab, and give subscribers the link to each group call.
- Protect the Service and comply with law: prevent fraud and abuse (such as multiple free accounts), enforce our Terms, and meet legal and tax obligations.
We do not use your data for targeted advertising, and we do not use automated decision-making that has legal or similarly significant effects on you.
4. Legal bases (EEA and UK users)
If you are in the European Economic Area or the United Kingdom, we rely on these legal bases:
| Purpose | Legal basis |
|---|---|
| Providing your account, study features and subscription | Performance of our contract with you |
| Billing records, tax and legal compliance | Legal obligation |
| Security, fraud prevention, improving the Service, service emails | Our legitimate interests in running a safe, working product |
| Marketing emails and non-essential cookies | Your consent, which you can withdraw at any time |
5. How we share information
We do not sell your personal information or share it for cross-context behavioral advertising. We share it only with:
| Recipient | Why | Examples |
|---|---|---|
| Service providers | Hosting (including our database, which runs on our own server), email delivery, payments and tax calculation, and live code previews. They may use data only to provide services to us. | Hostinger (hosting), Google Workspace (email delivery), Stripe (payments), CodeSandbox (runs live previews of code you write on React cards) |
| Sign-in providers | Confirming who you are, if you choose to sign in with them | Google, GitHub |
| Discord | Running our community server, if you connect your Discord account | Discord |
| Zoom | Hosting our group calls, if you join one | Zoom |
| Legal and safety | To comply with law, respond to valid legal requests, or protect rights and safety | Courts, law enforcement |
| Business transfers | If we are involved in a merger, acquisition or sale of assets, under this policy's protections | A buyer or successor |
We may share aggregated or de-identified statistics that cannot reasonably identify you, such as how many cards are reviewed each week.
6. Cookies and similar technologies
We use cookies only to keep you signed in and to make the app work.
- Essential: sign-in sessions and security, and short-lived cookies that hold a sign-up or Discord connection in progress. These are required, so they cannot be turned off. Checkout happens on our payment processor's page, which sets its own cookies.
- Preferences: None. Study settings, such as how many cards a session serves, are saved to your account rather than in cookies.
- Analytics: None.
You can block or delete cookies in your browser settings, but the app will not work without essential cookies.
7. Data retention
We keep personal information only as long as we need it for the purposes above.
| Data | How long we keep it |
|---|---|
| Account and study activity | While your account is active; deleted within 30 days after you delete your account |
| Billing and tax records | As long as tax and accounting law requires, typically 7 years |
| Support messages | 2 years after the conversation ends |
| Server and security logs | 90 days, unless needed to investigate abuse |
| Backups | Overwritten on a rolling basis within 30 days |
Discord messages are stored by Discord and governed by its retention settings.
8. Your rights and choices
Depending on where you live, you may have the right to:
- Access the personal information we hold about you and get a copy in a portable format.
- Correct information that is wrong or incomplete.
- Delete your information, subject to records we must keep by law.
- Object to or restrict certain processing, and withdraw consent where we rely on it.
- Opt out of the sale or sharing of personal information or targeted advertising. We do not do either.
- Not be discriminated against for exercising these rights.
These rights apply to residents of the EEA, UK, California and other US states with consumer privacy laws, and we extend them to all users where practical.
How to make a request. Email rawswe@masteringswe.com from the address on your account. We may need to verify your identity. We will respond within the time the law requires, generally 30 days (45 days for US state law requests). An authorized agent may submit a request for you with proof of authorization. If we deny your request, you may appeal by replying to our decision.
If you are in the EEA or UK, you can also complain to your local data protection authority.
Email choices. We do not currently send non-essential emails; if we start, you will be able to unsubscribe using the link in them. Service and billing emails are still sent while you have an account.
9. Security
We protect your information with measures such as encrypted connections (HTTPS), hashed passwords, access controls that limit who on our side can see data, and payment handling by a PCI-compliant processor. No system is perfectly secure, so we cannot guarantee absolute security. If a breach affects your personal information, we will notify you and the authorities as the law requires.
Please use a strong, unique password and tell us at rawswe@masteringswe.com if you suspect unauthorized access.
10. Children
The Service is not for anyone under 16, and we do not knowingly collect personal information from children under 13. If you believe a child has given us personal information, contact rawswe@masteringswe.com and we will delete it.
11. International transfers
We are based in the United States, and our service providers may process data in the US and other countries. Those countries may have different data protection laws than where you live. When we transfer personal information from the EEA or UK, we rely on safeguards such as the European Commission's Standard Contractual Clauses (and the UK addendum) or a provider's certification under the EU-U.S. Data Privacy Framework.
12. Changes and contact
We may update this policy as the Service changes. We will change the "Last updated" date at the top. If a change is material, we will also notify you by email or in the app before it takes effect.
Contact us: Mastering SWE LLC, rawswe@masteringswe.com.