Privacy Policy
Last updated: 3 July 2026
Shutoku is built by Systems Atlas Project. This policy explains what data we collect, how we use it, and your rights regarding that data.
What we collect
When you create an account, we collect:
- Your email address
- A hashed version of your password (we never store your password in plain text)
- Your vocabulary and review data — words you've added, review schedules, and progress records
We do not collect analytics, crash reports, location data, or any other personal information.
How we use your data
Your data is used solely to provide the Shutoku service:
- To authenticate you and maintain your account
- To sync your vocabulary and review data across your devices
- To send password reset emails when you request them
We do not sell your data. We do not share your data with third parties. We do not use your data for advertising.
Where your data is stored
Your data is stored securely on servers hosted by Railway (railway.app) in the European Union. Passwords are hashed using bcrypt before storage. Authentication tokens are signed with industry-standard JWT encryption.
We use Resend (resend.com) to send transactional emails — specifically password reset emails. We do not send marketing emails. Your email address is never shared with Resend beyond what is necessary to deliver these emails.
Data retention
Your data is retained for as long as your account exists. You can request deletion of your account and all associated data at any time by emailing shutoku@systemsatlasproject.com.
Your rights
You have the right to:
- Access the data we hold about you
- Request correction of inaccurate data
- Request deletion of your data
- Export your data
To exercise any of these rights, contact us at shutoku@systemsatlasproject.com.
Children
Shutoku is not directed at children under 13. We do not knowingly collect personal information from children under 13.
Changes to this policy
If we make material changes to this policy, we will update the date at the top of this page. Continued use of the app after changes constitutes acceptance of the updated policy.
Contact
If you have any questions about this privacy policy, please contact us at shutoku@systemsatlasproject.com.