This Privacy Policy describes how Nychorium ("we," "us," or "our") handles information when you use our website and AI chat service (the "Service"). By using the Service, you agree to this policy.
Summary
Nychorium is built to minimize what we hold. We do not store readable copies of your chat messages or attachments. By default, your conversation history stays on your device only, encrypted locally. Optional Chat Sync and Memory (both off by default) can store end-to-end encrypted ciphertext on our servers — we cannot read it without your recovery key. When you send a message, it passes through our API and an AI inference provider in memory — neither side writes your conversation content to permanent readable storage.
Information we collect
Account information
When you sign in via magic link, we collect your email address to authenticate you and associate your account with billing and usage limits. We do not use passwords.
Billing and payments
If you purchase Pro access, you can pay by credit/debit card or by cryptocurrency:
- Card payments are processed by Stripe, Inc. Your card details are entered on Stripe's secure checkout and are handled by Stripe — we never receive or store your full card number, CVC, or bank details. We receive a Stripe customer identifier and your subscription status so we can grant, renew, and manage your access. Stripe processes your payment information as a data controller under Stripe's Privacy Policy.
- Cryptocurrency payments are processed by NOWPayments, a non-custodial crypto payment processor. We receive confirmation that a payment was made and associate it with your account. Payments can be made in Bitcoin, Ethereum, USDC, or other supported cryptocurrencies.
We do not collect or store credit card numbers or bank account information on our servers.
Usage metadata — not message content
To enforce plan limits and operate the Service, we store non-content metadata, specifically:
- Anonymous conversation identifiers (UUIDs)
- Token counts per conversation (numbers only, never message text)
- Monthly usage counters per model and image generation (numbers only)
- Account creation timestamp and subscription status
- Rate-limit counters to prevent abuse
This is how we know how much you have used the Service without knowing what you said.
Usage after account deletion
If you delete your account, we remove your user record, encrypted Chat Sync and Memory blobs, and other account-scoped data. To prevent abuse (such as deleting and re-registering to reset free-tier limits mid-month), we retain monthly usage counters for the current calendar month keyed to a one-way hash of your email address — not your message content. When you sign up again with the same email, those counters still apply until your usage period expires. We do not retain this ledger beyond what is needed for billing and limit enforcement.
Support tickets
If you use Support chat and confirm opening a ticket for human follow-up (for example a bug report, complaint, or issue the support assistant cannot resolve), we store the entire Support conversation from that thread on our servers so our team can respond. We do not share your other chats or any other account information — only your account email, a category, a short summary, and ticket status. Support tickets are deleted or anonymized when no longer needed for support, subject to legal retention requirements.
Messages during processing
When you chat, your browser sends your messages (and any attachments) to our API server. Our server processes them transiently in memory — it constructs the request, forwards it to our AI inference provider, and streams the response back to you. We do not write readable conversation content to our database, to application logs, or to any other persistent readable store. If you enable Chat Sync, encrypted ciphertext of saved history may be stored as described under "Chat Sync feature."
Requests sent for AI inference are anonymized: they carry your message content and any attachments, but not your email, account identifier, or other information that identifies you. The inference request is not linked to your identity.
Our AI inference provider is selected specifically for privacy-conscious handling. It processes requests without logging conversation content. The request-response cycle is in-memory on both our side and the provider's — when the stream ends, neither side holds a copy of what was said.
If you include attachments (documents, images), the content of those files is sent to the provider as part of the same inference request and subject to the same in-memory handling. We do not maintain a server-side library of uploaded files.
Chat history on your device
Conversation history shown in the app is stored in your browser. It is encrypted with AES-256-GCM using a key that is generated on your device and stored in your browser's IndexedDB as a non-extractable CryptoKey — the raw key bytes are never accessible to JavaScript or transmissible to any server. We have no copy of this local key and cannot decrypt history stored only on your device.
With Chat Sync off (the default), history is not synced across browsers or devices. If you clear this browser's site data, that local history is permanently deleted — even to you — and there is no server backup to restore from unless you had Chat Sync enabled.
Chat Sync feature
Chat Sync is an optional feature that is off by default. When it is off, chat history stays on the device as described above, and nothing in this section applies to you.
When you turn Chat Sync on, Nychorium can keep your saved chat history available across your signed-in devices. Each conversation is encrypted on your device with a key derived from a recovery key that only you hold before it is uploaded. Our servers store only the encrypted ciphertext — we do not hold your recovery key and cannot read your synced chats. If you lose your recovery key, your synced chats cannot be recovered by anyone, including us.
Chat Sync does not change how live messages are handled when you ask for a reply. Message content is still processed transiently for inference, the same anonymized way as described under "Messages during processing." Sync only controls how saved chat history is stored and copied between your devices.
To help you manage devices that have synced, we store a device label (for example "Chrome on macOS"), a random device identifier, and first/last sync timestamps. This is non-content metadata — not your messages.
You can turn Chat Sync off, delete synced copies from the server, or generate a new recovery key in Settings → Chat Sync. Deleting synced copies or turning sync off removes the server-side ciphertext; generating a new recovery key permanently wipes synced chats tied to the old key. Local history on each device is controlled by your browser as described above.
Memory feature
Memory is an optional feature that is off by default. When it is off, no memories are created, stored, synced, or used, and nothing in this section applies to you.
When you turn Memory on, Nychorium keeps a small set of durable facts about you (for example a name, a preference, or an ongoing project) so it can personalize replies across conversations. Each memory entry is encrypted on your device with a key derived from a recovery key that only you hold. The encrypted entries can sync across your devices, but our servers store only the encrypted ciphertext — we do not hold your recovery key and cannot read your stored memories. If you lose your recovery key, your synced memories cannot be recovered by anyone, including us.
To decide what is worth remembering, to keep a compact summary current, and to surface relevant memories during a chat, memory content is processed transiently. In those moments it is sent to our server and AI models in memory, handled the same anonymized, non-stored way as your chat messages, and then discarded. We do not retain a readable copy; the only persistent record on our infrastructure is the encrypted blob.
You can view, edit, add, or delete individual memories at any time in Settings → Memory, or delete all of them at once. Deletion is permanent: a deleted memory is destroyed, not archived. Generating a new recovery key permanently wipes the existing encrypted memories tied to the old key.
Infrastructure and security data
Our hosting and networking layer (Cloudflare) processes standard technical data — IP address, request timing, TLS metadata, and error signals — to deliver and protect the Service. This is handled at the infrastructure level and governed by Cloudflare's own policies. We configure our application layer to avoid logging message bodies in error or access logs.
What we do not collect for storage
- A readable, server-side copy of your main chat transcripts
- A server-side archive of files you upload
- A readable, server-side copy of your synced chats or saved memories (if you enable Chat Sync or Memory, we hold only encrypted blobs we cannot decrypt)
- Advertising identifiers, behavioral profiles, or tracking pixels
How we use information
We use the information described above to:
- Provide, maintain, and improve the Service
- Authenticate you and manage your account
- Process subscriptions and prevent fraud
- Enforce free-tier and rate limits
- Respond to support requests, including support tickets opened from Support chat
- Respond to legal obligations
- Protect the security and integrity of the Service
Service providers
We rely on third parties that process data on our behalf, including:
- Cloud infrastructure: Cloudflare (hosting, CDN, Workers runtime, database)
- AI inference: a privacy-first inference provider that processes requests in-memory without storing conversation content
- Payment processing: Stripe (credit/debit card subscriptions) and NOWPayments (non-custodial crypto processor)
- Transactional email: a delivery service used only to send magic-link sign-in emails
These providers receive only what is necessary for their function. We do not sell your personal information to any third party.
Retention
- Support tickets: retained while open and as needed to resolve your request; resolved tickets may be kept for a reasonable period for support quality and legal purposes.
- Account and billing records: retained while your account is active and as required by tax, accounting, and legal obligations afterward.
- Usage metadata: retained as long as needed to operate billing and limits. Usage counters keyed to a hashed email identifier may be retained after account deletion to prevent limit abuse; they reset when your usage period expires.
- Magic-link tokens: short-lived; invalidated immediately on use or at expiry (15 minutes), whichever comes first.
- Message content: not retained in readable form after the inference request completes. Unless you enable Chat Sync, no persistent copy exists on our infrastructure.
- Local chat history: controlled entirely by you via your browser. Clear your browser's site data to remove it.
- Chat Sync (if enabled): stored as encrypted blobs and device metadata we cannot read, kept until you delete synced copies, rotate your recovery key, turn sync off, or delete your account. Live message content during a chat remains transient and is not retained beyond the encrypted blob.
- Memory (if enabled): stored as encrypted blobs we cannot read, kept until you delete the memories, rotate your recovery key, or turn the feature off and clear it. Memory content processed during a chat is transient and not retained beyond the encrypted blob.
Security
We use industry-standard practices including encrypted transport (HTTPS/TLS), access controls on backend systems, httpOnly cookies for session tokens (never localStorage), and minimal data retention. Local chat history uses a non-extractable device key we never receive. Optional Chat Sync and Memory use end-to-end encryption with a recovery key only you hold — our servers store ciphertext we cannot decrypt.
No system is completely secure. We cannot guarantee absolute security, but our architecture is designed so that the most sensitive data — what you actually say — is either kept on your device or stored only in encrypted form we cannot read.
Your choices and rights
Depending on where you live, you may have rights to access, correct, delete, or restrict processing of your personal information. To exercise these rights, contact us at privacy@nychorium.com. We may need to verify your identity using the email address on your account.
You can stop using the Service at any time. Clearing browser site data removes all on-device chat history. Account deletion is available in Settings inside the app; we will delete your account data except where retention is required by law or for abuse prevention (see "Usage after account deletion" above). You may also email privacy@nychorium.com to request deletion.
Children
The Service is intended only for adults aged 18 or older (or the age of majority in your jurisdiction, if higher). It is not directed to minors, and we do not knowingly collect personal information from anyone under 18.
International users
If you access the Service from outside the United States, your information may be processed in the United States or other countries where our infrastructure providers operate. Those locations may have different data protection laws than your home country.
Changes to this policy
We may update this policy from time to time. We will post the revised version on this page with an updated date. Continued use after changes constitutes acceptance of the updated policy.
Contact
Privacy questions: privacy@nychorium.com
See also our Terms of Service.