Twyl

Privacy

Version 2026-10-23

This Privacy Policy explains what personal data Twyl collects through its online services—the Twyl platform and its websites—why it collects it, how it uses and protects it, when it may share it, and what rights and choices you have.

Who operates Twyl

During the private preview, Twyl is operated by Mathieu Demarne in Seattle, Washington, United States. In this policy, “we,” “us,” and “our” refer to the person or company operating Twyl. Any person who later assists in operating Twyl will be required to comply with this policy.

If the project proceeds to public preview and Twyl is transferred to a company, that company will replace us for purposes of this policy, maintain the security of your books, and assume the commitments made in this policy and the Terms. We will notify you of policy changes. The same applies if Twyl is transferred to another person or organization.

This policy applies to writers wherever they live. Twyl provides the same rights described here to every writer.

Ownership and sensitive information

To the extent permitted by applicable law, you retain ownership of your manuscripts, notes, style sheets, conversations with Twyl, and any text Twyl drafts for you. Twyl claims no ownership rights in those materials.

Twyl does not request health information or other sensitive personal data. If your writing contains such information about you or another person, Twyl stores and processes it only to provide the service you request, as it does with the rest of your book. Twyl is not intended to store passwords, payment details, identity documents, medical records, or similar records. You should not include those materials in your books.

Twyl does not sell your data, display advertising, or share data with any person for advertising purposes.

Data stored and storage locations

Twyl stores your books as files on the servers that operate Twyl, in Switzerland. These files include each chapter, each note, your conversations, the history of every commit, and text you have entered but not yet committed. A separate database, also in Switzerland, stores your account information: your name, the address you used to sign in, the titles of your books, and a record of the model-processing use attributable to each call. The database does not store the contents of a book, except for a passage you choose to submit with a feedback thumb.

The database also stores the model you selected, the amount of processing use remaining for the month, the date of your last visit, the version of the Terms you accepted and the date of acceptance, and the current size of each book measured in chapters, words, Twyls, and notes. These are numerical or administrative records; they do not contain anything you wrote. Changes in a book’s size over time are recorded as telemetry, as described below.

A feedback thumb, whether positive or negative, records your selection and the Twyl action you rated. The line you write with the feedback thumb and any passage you choose to submit are stored in the database. Twyl personnel may review them to improve the service. A submitted passage is deleted after 90 days. The remaining feedback data is deleted when you delete the book or your account. You may delete every line and passage you submitted at any time by selecting “Delete what I sent” under “Settings” in the menu under your name. Feedback thumbs remain.

Twyl personnel can see the amount and type of service use associated with your account, including the records described above and actions recorded under your account. They can read feedback you submit. Twyl does not provide them with a means to open a book. We can access the files in which a book is stored only when you request it, when a fault cannot be repaired by other means, to investigate a report that a book contains illegal content or seriously breaches the Terms, or when required by law. We record each such access and notify you afterwards unless the law prohibits notification.

Twyl receives the internet address from which your browser connects. It uses that address to limit excessive requests and maintain security. Twyl does not store it in its database or telemetry, although telemetry may record the country to which it points. The sign-in service retains it in its sign-in records for up to 30 days.

Signing in sets a cookie named `twyl` that identifies your session to Twyl. It remains active until two weeks after your last visit, and signing out ends it. The sign-in service may set its own cookies during sign-in. Twyl sets no other cookies and does not run advertising or browser analytics. Accordingly, Twyl does not request consent for cookies.

Your browser stores your workspace preferences, including which panels are open, their width, and the light or dark setting. It also stores the text you enter into a chapter until that text reaches the book, so that closing a tab does not cause data loss. The browser deletes that copy after 30 days. Both types of data remain on your device. Deleting your account does not delete browser data; you can clear this site’s data in your browser to remove it sooner.

Model processing

A model is invoked only when you select Verify or Catalogue, or send a message in the chat. The material sent for that call depends on the action and may include the chapter or passage being read, relevant notes, your message, and other context needed to answer it. It is sent to the model provider only to provide that action, not for any other purpose.

Twyl does not use anything you write to train a model, regardless of the model you select.

You may select the model under Settings in the menu under your name, and you may change that selection at any time. A call already in progress is completed using the model selected when the call began.

General. General is a general-purpose model supplied by a commercial provider. It is the fastest and most thorough option. Content read by General is sent to that provider outside Switzerland for processing. The provider does not use that content to train its models and may retain it for a limited period to monitor abuse. We may, at any point in time, use either:

  1. Claude: see Anthropic's privacy policy.
  2. GPT: see OpenAI's privacy policy.
  3. Azure: see Microsoft Foundry's privacy and security page.

Private. Private is an open-weight model operated in Switzerland by a Swiss provider. Content read by Private remains in Switzerland. The provider’s terms state that the content is neither stored nor used for training. Private operates more slowly.

Private runs at Infomaniak Network SA in Geneva, Switzerland. Infomaniak keeps what it reads only for as long as it takes to answer and does not use it to train models (LLM API Special Conditions, article 6). Refer to:

  1. Infomaniak confidentiality policy.
  2. Infomaniak AI API's usage conditions.

For each provider, you may refer to their privacy policy. We choose models based on their performance on Twyl after benchmarking using public-domain books.

External sources

Twyl’s chat can query sources outside your book only if you enable that function. Each source is controlled by a switch under Sources in the chat, configured separately for each book and disabled by default. When you enable a source, the chat may use it when a question requires it. When you disable it, the chat cannot use it. Your settings for one book do not affect your other books.

When a source is enabled, Twyl's server, rather than your browser, sends short search requests to that source. The search may contain words from your question or your book.

These providers receive the search and the address of Twyl’s server. They do not receive your name, email address, account information, or chapters. Wikimedia retains request logs for up to 90 days. The OpenStreetMap Foundation retains server logs under its own privacy policy. Twyl retains a copy of OpenStreetMap’s public responses for one day so that repeated searches are sent only once. That copy contains the response and does not identify the person who requested it.

Your research folder is a third source. It reads files that you added to your book and sends no information outside Twyl.

Wikipedia and OpenStreetMap run outside Switzerland. If you chose the Private model to keep all processing in Switzerland, leave these sources off.

Telemetry

Twyl collects operational telemetry so that we can assess use, performance, failures, and misuse. Telemetry may record that a request was made, the type of address involved, how long the request took, and whether it succeeded; that a pass ran over a chapter and the processing use it incurred; and that you performed actions such as signing in, committing a chapter, selecting Verify, sending a message, opening the Arc, or using a feedback thumb. Telemetry contains identifiers, counts, and durations. One identifier is the number Twyl assigned to your account; it does not contain your name or address. A chapter is identified by its id, which is derived from its title. Telemetry contains no line of a book, note, or message. When an error occurs in the interface, the page may report the error type, the location in Twyl’s code, the screen in use, the light or dark setting, and the approximate window width. It does not contain anything you wrote or the address of a book. Telemetry is stored in Switzerland with the servers.

Twyl retains telemetry for one year from when it is recorded. When you delete your account, Twyl no longer holds your name and address, so the number no longer identifies you. While your account exists, we can associate the number with your name through the usage page. Fourteen days after account deletion, when database backups have expired, no data held by Twyl links the number to you.

Twyl uses service providers to operate the service. Each provider may use your data only to perform services for Twyl, under a contract that limits that use.

  • Cloud provider. Microsoft Azure operates Twyl's servers, database, backups, and telemetry in Switzerland.
  • Sign-in service. Microsoft Entra ID stores your name, sign-in address, and password or the link to the Google or Apple account used to sign in. It stores this information in Europe. If you sign in with Google or Apple, those providers receive information about your sign-in to Twyl under their own privacy policies.
  • Model provider. Processes data according to the model you selected, as described under "Model processing". The provider of General may process content in the United States or another country where it operates infrastructure, may retain it for up to 30 days to monitor abuse, and longer for content its systems flag, and may permit staff to review a passage flagged by its systems. The provider of Private processes content in Switzerland, and its terms state that it retains nothing.
  • Email provider. Infomaniak operates in Switzerland and carries messages you send to us and our replies.
  • Owner and operator access. We access Twyl data from the United States.
  • Authorities. May receive data when the law requires us to disclose it. Because we and some providers are American, United States law may compel us to disclose data wherever that data is stored.

Where data is transferred to the United States, the applicable provider’s contract includes standard contractual clauses, or the provider is certified under the Data Privacy Framework.

Each processing activity relies on one of the following bases:

  • Service provision. To provide the service you requested, including your account, books and their history, sign-in, model calls you initiate, export, and deletion.
  • Legitimate interests. To operate telemetry, assess when Twyl is slow, failing, or misused, understand how it is used, limit requests, maintain security, and retain a record that an account was previously permitted to access Twyl. Twyl weighs these interests against your interests. You may object to this processing as described below.
  • Your choice. To process a passage you submit with a feedback thumb. You may withdraw that choice by selecting “Delete what I sent” or by writing to us; we will then delete the passages you submitted. Withdrawal does not reverse processing that already occurred.
  • Legal obligation. To respond to an authority that can compel us and to retain a record of a breach.

Twyl does not use automated decision-making to produce a legal or similarly significant effect on you. We decide whether to permit an account to access Twyl.

Retention periods

  • Books, notes, conversations, and history. Retained until you delete the book or your account.
  • Books after closure. If we close your account or Twyl closes, retained for an additional 30 days so they can be sent to you on request, then deleted.
  • Account database. Retained until you delete your account. One record remains as described under “Deleting your account”.
  • Sign-in information. Retained until you delete your account. The sign-in service then removes it, and it is deleted within 30 days.
  • Feedback. A submitted passage is retained for 90 days. The remaining feedback data is retained until you delete the book or your account.
  • Telemetry. Retained for one year.
  • Internet address. Not retained by Twyl; retained by the sign-in service in its records for up to 30 days.
  • Backups. Retained for up to 30 days for books and up to 14 days for the database, as described under “Backups”.
  • Browser data. The copy of text you entered is retained for 30 days. Workspace preferences remain until you clear them.
  • Messages to us. Retained for the time required to respond and for no more than one year after your last message.

Exporting your book

The Export function in a book’s top bar can export the book at any time as Markdown chapters, a Word file, or a complete book with its notes. The complete export consists of plain files that can be read without Twyl.

Deleting your account

The Delete account function in the menu under your name removes your books, their history, your conversations, your processing-use records, your feedback thumbs and submitted material, and your sign-in from every device. Account deletion is permanent. Download any book you wish to retain before deleting your account.

Telemetry records of your activity remain for up to one year under a number that no longer identifies you. Twyl also requests deletion of your sign-in-service record. One database record remains to show that an account was previously permitted to access Twyl; it contains no name or address.

Backups

Backups of books are retained for no more than 30 days, and database backups for no more than 14 days. Accordingly, within 30 days after account deletion, your books are removed from all backups.

Your rights

Regardless of where you live, you may ask us:

  • Access. To tell you what Twyl holds about you and provide a copy.
  • Correction. To correct inaccurate information.
  • Deletion. To delete your information; Delete account also performs this action.
  • Portability. To provide your information to you or a person you designate in a commonly used format; Export provides this for your books.
  • Objection and restriction. To object to processing based on Twyl’s legitimate interests, and to restrict it while we review your request. We stop unless we have compelling grounds to continue, such as keeping Twyl secure and working.
  • Withdrawal. To withdraw a choice you previously made at any time.

Write to contact@twyl.ink. We will respond within one month at no cost. A complex request may require an additional two months; we will explain the reason for the delay. We may request information needed to verify that the account is yours.

If you believe Twyl has processed your information incorrectly, you may complain to us. We will confirm receipt within 30 days. You may also complain to the data protection authority where you live.

United States disclosures

Twyl does not sell or share personal information, use it for targeted advertising, or track you across other sites. A Do Not Track or Global Privacy Control signal therefore does not change any Twyl processing.

Security

Twyl encrypts every connection and encrypts books, the database, and backups while they are stored. A writer's books are accessible only through that writer's account, except as described above. An account created with an address and password also requires a code sent by email (MFA).

If a breach creates a risk to your data, Twyl will notify you without delay and will notify the authorities identified by law within the applicable period.

Children

Twyl is intended for people aged 18 or older, as stated in the Terms. If we learn that an account belongs to a person under 18, we will close the account, offer to send the person's books, and then delete the data Twyl holds.

Changes

When this policy changes in a material way, the Terms will change with it, and you will be asked to accept the new terms before continuing to use Twyl. If Twyl proposes a new use of data it already holds, Twyl will notify you before that use begins and will obtain your consent first where required by law. Twyl will not begin using your writing to train a model.