Privacy Policy
Your privacy matters. Here's how we protect and handle your personal information.
Our Privacy Principles
Yostar Account Integration
How we sync your Arknights game data
Myrtle uses Yostar's official OAuth system to sync your Arknights account data. Here's how it works:
How Authentication Works
When you log in, you enter your email address in our app. Yostar sends a verification code directly to your email. You enter that code to authenticate. We never see or store your Yostar password - authentication is handled entirely by Yostar's servers. Your email address is only used during the authentication process and is not stored in our database.
What We Receive from Yostar
Upon successful authentication, Yostar provides us with a session token that allows us to fetch your public game data: operator roster, levels, promotions, skill masteries, modules, stage progress, base layout, inventory, and account statistics. This is the same data visible in your in-game profile.
We are not affiliated with Hypergryph or Yostar. We access your data through the same APIs the official game client uses. You can revoke our access at any time by requesting a deletion of your Myrtle account via the Discord server.
Information We Collect
Understanding what data flows through our system
Account Information
When you create an account via Yostar OAuth, we store:
- Arknights UID and nickname - Your in-game identifier and display name
- Profile settings - Your Myrtle preferences: theme, accent color, profile visibility, leaderboard opt-in, and notification settings
Note: We do not store your email address. It is only used during the Yostar authentication process to receive your verification code and is not saved to our database.
Game Data (Synced from Arknights)
When you sync your account, we fetch and store:
- Operator roster - All operators you own, including level, promotion, trust, potential, skill levels, masteries, and equipped modules
- Stage progress - Mainline, sidestory, and activity stage completion status
- Roguelike & Sandbox progress - Integrated Strategies themes, endings, buffs, and Reclamation Algorithm data
- Base layout - RIIC building configuration and efficiency data
- Medals and achievements - Your collection of in-game medals
Saved Configurations
Content you save on Myrtle:
- DPS calculator configurations - Saved operator configurations and comparison setups
Technical Data
We may temporarily process:
- Error logs - Diagnostic data to help us fix bugs, stored temporarily
Note: Your IP address is not collected or stored. All API requests are routed through our Next.js server, which handles communication with our backend internally. Rate limiting is applied at the server level, not based on individual user IPs.
How We Use Your Information
The purposes behind our data collection
User Settings & Profile Visibility
Control how your information is displayed
Your settings page gives you full control over how your data is shared with others:
Profile Visibility
Choose whether your profile is public (anyone can view), friends-only, or completely private.
Leaderboard Participation
Opt in or out of appearing on public leaderboards. Your scores are still calculated but won't be displayed publicly if you opt out.
What's Publicly Visible (When Profile is Public)
- • Your Arknights nickname and UID
- • Your operator roster and account scores
- • Your leaderboard rankings (if opted in)
- • Your profile avatar and selected assistant
What's Always Private
- • Your authentication tokens and session data
- • Your settings and preferences
- • Your saved DPS calculator configurations
Data Security & Storage
How we protect your information
We implement security measures to protect your personal information:
Encryption
All data transmitted over HTTPS with TLS encryption
JWT Authentication
Secure token-based sessions with automatic expiration
Server-Side Rate Limiting
Rate limits applied at server level without tracking user IPs
Redis Caching
Static data cached with 1-hour TTL for performance
Database
Your data is stored in PostgreSQL with proper constraints and transactions. Game data is fetched fresh from Yostar's servers when you sync - we store a copy so you can access your profile and leaderboard features without re-authenticating.
While we strive to protect your information, no method of transmission over the internet is 100% secure. Our code is open source on GitHub, so you can review our security practices.
Your Rights & Choices
Control over your personal data
You have the following rights regarding your personal information:
Third-Party Services
We interact with the following third-party services:
- Yostar/Hypergryph: We use Yostar's OAuth system to authenticate you and fetch your game data. We are not affiliated with Yostar or Hypergryph - Myrtle is an independent fan project.
- Arknights Game Servers: We fetch game data from official servers (EN, JP, KR, CN, TW, Bilibili) to provide up-to-date operator information, assets, and your synced account data.
- Hosting Infrastructure: Our servers and databases are hosted on secure cloud infrastructure.
We do not sell, trade, or rent your personal information to third parties. We do not run ads or use your data for marketing.
Children's Privacy
Our Service is not directed to individuals under the age of 13. We do not knowingly collect personal information from children under 13. If you become aware that a child has provided us with personal information, please contact us and we will take steps to delete such information.
Changes to This Policy
We may update this Privacy Policy from time to time to reflect changes in our practices or legal requirements. We will notify you of any material changes by posting the new policy on this page and updating the "Effective Date" at the top.
We encourage you to review this Privacy Policy periodically. Your continued use of the Service after changes are posted constitutes your acceptance of the updated policy.
Contact Us
Questions about your privacy?
Discord
Join our Discord serverSource Code
github.com/Eltik/myrtle.moeYour Privacy is Our Priority
We're committed to transparency and giving you control over your data. If you have any questions or concerns, we're here to help.