Privacy Notice

Controller

The data controller is Andrey Kovlyagin, a natural person acting as the individual maintainer of Chains. Chains is not presented as a registered company product in this beta.

Postal address: Carrer Muntaner 22, PPL 3, 08011 Barcelona, España

For privacy requests, deletion requests, or other data questions, email privacy@chains.design.

Registration and sign-in

To register or sign in, you enter your email address. Supabase, the authentication provider, stores the address as a pending sign-in identity and sends an email with a one-time link and code. No Chains profile or workspace is created and no workspace invitation is used until you open that link and confirm the address.

After you confirm it, you enter your name and last name. When you create a new workspace, you also choose its preferred data region. Chains records the date and time you accepted the Terms of Use and the version you accepted. When you join through a workspace invitation, Chains checks that the invitation matches your confirmed email address and records that it was used.

The legal basis is taking the steps you request before entering into the Terms of Use and then performing them. If you confirm your address but do not finish registration, or never open the link, the pending identity remains in Supabase until you ask for it to be deleted. Supabase also keeps security records of sign-in requests to limit abuse.

Where your data is stored

Account data, workspace content, and uploaded files are currently stored in the Chains Supabase project in Frankfurt, Germany, whichever data region you choose; database backups are described below. The data region you select for a new workspace records your preferred future hosting region (EU or US). It is not yet a guarantee about where data is stored, and choosing the US does not move data to the United States.

Beta account and product data

If you create a beta account or join an invited workspace, Chains processes account, authentication, workspace, project, workflow, file, comment, and activity data needed to provide the beta app.

The legal basis is the performance of the Terms of Use you accept when you create an account. This data is kept while your account exists. Content you add to a workspace is available to the other participants of that workspace according to its access rules.

Chains is intended for ordinary design collaboration, such as reviewing PDF magazine layouts. It is not intended for sensitive categories of personal data, such as health data. Files you upload can still contain personal data about you or other people. Chains stores them as provided and does not inspect or classify their contents.

When your account is deleted, your email address and sign-in credentials are removed and you can no longer access Chains. Content you contributed to workspaces that other people still use, such as files, comments, and workflow records, stays in those workspaces so their work remains intact. Your name, position, and profile picture stay attached to that content so its history remains understandable to the workspace. You can ask for this remaining profile information to be anonymized by emailing privacy@chains.design.

This notice does not enable paid services, advertising, or marketing email. Those require separate review before they are introduced.

Chrome browser extension

The Chains browser extension handles your name, email address, account and workspace identifiers, sign-in codes and session credentials, workspace invitations, workflow settings, submitted links and files, and contribution and approval records. This data provides the sign-in, team workflow, and handoff features you request. Email is used for authentication and workspace invitations.

The extension reads the current tab's URL when you explicitly open its toolbar popup, so it can prefill a contribution. Opening the popup does not submit that URL as work. A URL is sent when you confirm a submission in the popup or select an eligible workflow turn in the "Send this page to Chains" context menu. The submitted full URL, including its query string and fragment, becomes part of the workspace contribution. The extension does not monitor ordinary navigation, collect your browser's browsing history, or read the contents of unrelated pages.

On the Chains invitation landing page, explicitly opening the extension reads the workspace invitation token and the separate one-time sign-in grant from the link. These are used to show and continue the invitation flow. The one-time sign-in grant is redeemed only when you choose Continue; opening the landing page alone does not sign you in or join a workspace.

Files are uploaded only after you explicitly select and submit them. Submitted URLs and files are available to authorised workspace participants according to the workflow and access rules. Opening incoming content or downloading a file requires an explicit action. The extension does not access your mailbox or scan files on your device.

The authentication session, including access and refresh tokens, is stored in extension-local storage to restore sign-in after browser or service worker restarts. A workspace invitation token bound to the signed-in recipient may also be stored temporarily until profile setup is completed. This onboarding data is cleared after successful profile setup or session removal. The one-time sign-in grant, workflow projections, contribution URLs, uploaded files, and file download URLs are not persisted in extension-local storage.

The production extension sends account and workflow requests to Chains at chains.design and authentication and file-storage requests to the Chains Supabase project over HTTPS. Chains uses the service providers described in this notice, including email delivery providers and PostHog for the limited server-side product analytics described below. The extension also periodically refreshes the signed-in user's tasks to update its badge and context menu; these refreshes do not collect browser activity.

Signing out removes the locally stored session and unfinished invitation onboarding. Workspace contributions remain available until removed through the applicable product controls or a deletion request is fulfilled. You can request access, correction, export, or deletion using the contact address in this notice.

Chains' use and transfer of information received through Chrome APIs adheres to the Chrome Web Store User Data Policy, including the Limited Use requirements. This data is used only to provide and support the extension's workflow features and related operations. It is not sold, used for advertising or credit decisions, or transferred for unrelated purposes. Transfers to service providers are limited to providing and supporting these features, or other cases permitted by the policy, such as security or legal obligations.

Authenticated product analytics

Chains uses limited server-side product analytics to understand whether beta users can configure templates, create chains, add work and approvals, and invite workspace members. Each event records a successful product action, such as creating a template, a template phase, a chain, or a content or acceptance commit, or sending a workspace invitation. It contains your internal user and workspace identifiers and your role. It does not include names, email addresses, file names, uploaded content, comments, or free text.

The legal basis is the controller's legitimate interest in measuring, maintaining, and improving the experimental beta. It is on by default, and you can turn it off at any time with the Usage analytics setting in Settings → Notifications. Product analytics events are retained for up to 12 months.

PostHog processes these events on behalf of Chains. Events are stored in PostHog EU Cloud in Frankfurt. PostHog and its subprocessors may perform limited processing outside the EEA under the safeguards in the PostHog Data Processing Agreement, including the EU-US Data Privacy Framework and Standard Contractual Clauses. Server-side product analytics does not place analytics cookies or analytics identifiers in your browser.

Optional browser analytics in the app

Separately, and only with your consent, the authenticated app sends browser analytics to understand whether beta users reach a signed-in session and which app sections they open. Each event contains your internal user and workspace identifiers, your role, a general section name such as projects, chain, or settings, an analytics device and session identifier, and basic browser and device details: browser, operating system, device type, screen size, language, and time zone. Events do not include page addresses, project, chain, or file identifiers, names, email addresses, file names, uploaded content, comments, or free text. PostHog receives your IP address with each request and is configured to discard it. Session replay, autocapture, and heatmaps are disabled.

The legal basis is your consent. Browser analytics stays off unless you tick the optional checkbox during registration or turn on Browser analytics in Settings → Notifications. Refusing it does not affect your access to Chains. Your choice applies to the browser where you make it. You can withdraw consent at any time in Settings; capture stops immediately in that browser and the stored analytics identifiers are removed. Browser analytics also stops while usage analytics is turned off.

After you opt in, PostHog stores an analytics identifier in a first-party cookie and local storage on your device. Chains stores your consent choice in a first-party cookie for 12 months. Browser analytics events are processed by PostHog in EU Cloud in Frankfurt under the same safeguards as authenticated product analytics and are retained for up to 12 months.

Error monitoring

The app and API report unexpected errors to Sentry so the maintainer can detect and fix failures. Error reports contain the error type and message, a stack trace without source file paths, the affected route, the environment, and basic browser or runtime details. User identity, cookies, request headers, request bodies, query strings, and form contents are removed before a report is sent.

Sentry receives the IP address of the reporting browser or server as part of the network connection but is configured not to store it with error reports. Chains does not use error reports to identify or profile users. The legal basis is the controller's legitimate interest in keeping the beta secure and working. Error reports are retained for up to 90 days.

Cookies, storage, and analytics

The public marketing site offers optional PostHog analytics, based on your consent, to measure visits to the landing page and clicks on the registration buttons across the marketing site. The cookie banner lets you accept or reject analytics with equal ease. Analytics is initially off and PostHog loads only after you accept it. Rejecting it does not affect your access to Chains.

Events contain an anonymous visitor identifier, the fixed public page path, and whether the action was a page visit or registration button click. We do not send names, email addresses, form contents, full URLs, query strings, campaign parameters, or referrers. We do not link marketing identifiers to app accounts. Client IP data is discarded and location enrichment is disabled. There are no advertising pixels, session replay, autocapture, or group analytics.

The first-party chains_marketing_consent cookie stores your choice for 182 days. After you opt in, PostHog uses theph_chains_marketing first-party cookie for an anonymous identifier and session state, and thechains_marketing_sdk_consent cookie for its capture preference, each for up to 182 days. Session storage entries with the ph_chains_marketing prefix support the current tab and session and normally expire when the tab closes. This storage is separate from the app's browser analytics storage.

You can change or withdraw consent at any time through Cookie settings in the footer. Withdrawal stops new collection immediately and removes the marketing analytics identifier cookie and session storage. Your cookie preference remains so we can respect it. Events are processed by PostHog EU Cloud in Frankfurt under the same transfer safeguards described above and retained for up to 12 months. The opted-in funnel undercounts total traffic because refusals, blocked analytics, and unavailable storage are excluded.

The authenticated app may use strictly necessary authentication and security storage to provide sign-in and beta app access. Optional browser analytics storage is used only after you opt in, as described above.

Operational logs

The public marketing routes may use short-retention operational logs to count visits and diagnose service issues. These public access logs do not store raw IP addresses, query strings, cookies, request bodies, email addresses, or form contents.

Public raw access logs are retained for 14 days. Host nginx error logs used for operations and security diagnostics are retained for 30 days.

Service providers

Chains uses these service providers as processors. Each processes personal data only on Chains' instructions under its data processing agreement with Chains.

• Supabase: authentication, database, and file storage. Data is stored in Frankfurt, Germany.
• Hetzner Online: hosting of the website, app, and API. Servers are located in Helsinki, Finland.
• Resend: delivery of sign-in, invitation, and support email, sent through Amazon SES in Ireland.
• PostHog: the authenticated product analytics and optional app and marketing browser analytics described above, stored in PostHog EU Cloud in Frankfurt, Germany.
• Sentry: the error monitoring described above, stored in Sentry's EU region in Germany.
• Cloudflare: DNS for chains.design and forwarding of email sent to chains.design addresses.

Some of these providers are established in the United States or use subprocessors outside the European Economic Area. Where personal data is transferred outside the EEA, it is protected by the EU-US Data Privacy Framework or the European Commission's Standard Contractual Clauses included in the provider's data processing agreement.

Email sent to chains.design addresses, including privacy@chains.design, is forwarded to the maintainer's personal Google Gmail mailbox and handled there. Google processes these messages under its consumer terms, which may involve processing outside the EEA. Avoid sending more personal data than your request needs.

Backups

The database is backed up daily, and each backup is kept for 7 days. Data you delete, or that is deleted at your request, can therefore remain in backups for up to 7 days before it is permanently removed. Backups are used only to restore the service after a failure. Uploaded files are not included in these backups.

Your rights

You can ask to access, correct, delete, restrict, or export your personal data, or object to processing based on legitimate interests, such as authenticated product analytics and error monitoring, by emailing privacy@chains.design. You can turn off usage analytics and withdraw browser analytics consent yourself in Settings → Notifications. Requests are answered within one month.

You can also lodge a complaint with the Spanish Data Protection Agency (Agencia Española de Protección de Datos) or with the supervisory authority in the EU country where you live or work.

Last updated

October 19, 2026.