Privacy Policy
Benjamin Yang operates QueryCraft and handles privacy requests at support@querycraft.online. You can learn without an account. We do not sell personal information or share it for advertising.
1. Data and retention
We use your email, authentication ID and verification status for sign-in; your nickname and consent date, version and URLs for membership; mission completions, import and verification times, review results and rewards for learning; optional ranking preferences, avatar and study-group membership for selected social features. These records remain until account deletion. Unfinished registrations may also request deletion. Level resets do not delete original verification history. We do not collect passwords, birth dates, identity documents or payment details. Membership requires confirmation that you are at least 16; no parental-consent process is provided.
Session identifiers and encrypted authentication tokens support sign-in for up to 30 days. Logout deletes the current session; account deletion removes all linked sessions. Expired sessions are cleaned up on subsequent authentication requests. Network and security logs may include IP, browser, request path, time, response and errors. Inquiry emails are retained for up to one year after resolution, unless a legal obligation requires separate retention and notice.
2. Your browser and SQL
Guest progress, SQL input and preferences remain in browser local storage. Importing progress transmits completed mission IDs. SQL text is processed by the server and learning database for execution and grading, but is not saved in the member progress store. Errors or security logs may contain parts of input; do not submit personal data or secrets. Teaching records are fictional. We use essential HttpOnly cookies: up to 10 minutes for an authentication flow and 30 days for a session. Blocking cookies affects login. Clearing browser storage removes guest progress; account deletion does not remove browser guest data. We do not use advertising tracking cookies.
3. Providers and international processing
Supabase Pte. Ltd. provides authentication and database storage in Seoul, South Korea, with operational/support processing involving Singapore, the US and its published subprocessors. Authentication and linked member records are removed on account deletion. Our current Free project has no daily database backups; platform logs follow the plan's retention policy. Supabase privacy/contact · Subprocessors.
Vercel Inc. hosts the site and APIs; server functions run in Seoul. Delivery and security infrastructure may process request information in the US and other countries. Runtime logs use the current plan's short retention window; security/platform records follow Vercel's policies. We have not configured a separate log export destination. Vercel privacy/contact.
Resend (Plus Five Five, Inc.) sends verification emails from North Virginia, US and stores messages in the US. It receives the recipient, sender, message including the one-time code and delivery events. Standard message/log retention is 30 days; backups may remain for up to 7 additional days. We can forward early deletion requests to support@resend.com. Resend retention details.
Necessary data is transferred over encrypted connections when you authenticate or use account features. Before sending an email or redirecting you to Google, we ask you to consent to the stated data use and international processing. You can decline or withdraw and continue as a guest, but email authentication and account storage will not be available. Where applicable, contract performance supports account services, legitimate interests support necessary security, and consent supports optional features. Applicable provider data-processing agreements and transfer safeguards, including standard contractual clauses, apply. Google sign-in is optional. Google supplies your email, account identifier, name and profile picture, which Supabase stores in authentication records until account deletion. We do not automatically publish your Google name or photo in rankings and do not access Gmail, Drive or contacts. Google processes sign-in requests and device/IP information in the US and globally under its own privacy policy and retention rules. You can revoke access through Google account connections; deleting QueryCraft records requires separate account deletion or a privacy request. Authentication consent is not marketing consent.
Support inquiries are received in a Resend inbox and copied to the operator’s Gmail for handling. Sender addresses, message bodies and attachments are processed by Resend and Google mail services, potentially in the US and other countries. Copies in both inboxes are deleted within one year after resolution. Replies are sent from support@querycraft.online. This does not grant QueryCraft access to users’ Gmail through Google sign-in. Google privacy policy.
The Contact form is available without signing in. We process the reply email address, subject and message to answer your inquiry. Signed-in users may prefill their account email and edit it without changing their account. Form inquiries are sent through Resend to the support inbox and copied to the operator’s Gmail using BCC, with the entered email as the reply address; the form does not accept attachments or send automatic receipt emails. Messages follow the support retention period above. Drafts remain only in the current page memory and are not saved in browser storage or the member database.
When you open the Contact form, Cloudflare Turnstile processes browser and network signals to prevent automated submissions. We validate its result on the server and do not send the inquiry if verification fails. See Cloudflare’s Turnstile privacy policy. We store keyed hashes of IP and email addresses, time windows and attempt counts in Supabase to limit repeated submissions. These records are not inquiry histories and cannot be used to read the original message. Expired rate-limit records older than 24 hours are removed on the next admission check; if there are no further checks, they remain until cleanup runs.
4. Public features and rights
Public rankings are off by default. Opting in displays your nickname, avatar, verified mission achievements, the highest verified level and mission numbers, review score and rank, not your email. Study-group members may see group rankings. You can opt out without losing learning access. We do not otherwise disclose data beyond service processing and your selected public features, except as required by law or at your request.
Contact us to access, correct, delete, restrict or object to processing, withdraw consent or exercise applicable portability rights. We verify identity minimally, usually with your account email, and aim to respond within 10 days or explain a lawful delay or refusal. Do not email codes, passwords or identity documents. You may complain to your local privacy regulator.
To delete your account, open the account dialog, choose Delete account and type DELETE to confirm. You can also delete an authenticated account before completing profile setup. After the deletion succeeds, we remove the authentication account and associated profile, learning progress, reviews, ranking records, sessions, memberships and owned study groups. The deletion cannot be undone. Guest data stored in your browser is not deleted; clear it separately if you wish. Provider logs and backups follow the retention policies described above, and messages already delivered to your inbox cannot be recalled. If you used Google sign-in, you can separately remove the connection in Google account settings. Information no longer needed is deleted without undue delay, subject to legal obligations. HTTPS, access controls, encrypted token storage and server-only secret keys protect records. We handle incidents and notifications under applicable law. Policy changes are dated and announced on the site; material changes receive advance notice and renewed consent where required. Request earlier versions by email.