Privacy policy¶

Last updated on 16 October 2026 (2026-10-16).

Sioul is a free and open-source desktop application, published by Aurélien Pierre under the GPL-3.0-or-later licence. This policy says what Sioul does with your data, and in particular with the data it receives from Google when you sign in with a Google account, and from Microsoft when you sign in with a Microsoft account for your mail.

In short¶

• Sioul runs on your device. There is no Sioul server.
• Your data stays on your device and in your own accounts: your mail provider, your calendar server, your Google account, your Microsoft account.
• Nothing is sent to the developer of Sioul. Nothing is sold, nothing is used for advertising, nothing is used to build profiles.
• Data leaves your device only to the services you add, and to the few others described below, each for a feature you choose.

Anyone can read Sioul's source code, to check what this policy says: github.com/aurelienpierre/sioul.

Who is responsible¶

Sioul is made and published by Aurélien Pierre. Since Sioul has no server, its developer never receives, stores or sees your data. Questions about this policy: see Contact.

How Sioul works¶

Sioul connects, from your device, to the services you add to it: your mail provider (IMAP and SMTP), your calendar and contacts server (CalDAV and CardDAV), Google, Microsoft. It keeps a copy of what it fetches in files in your own user folders, so that it can work without waiting for the network. Passwords and access tokens go to your system's keyring (the Secret Service on Linux, the Credential Manager on Windows, the Keychain on macOS, Android's KeyStore on a phone), never into a file.

Joining your other devices through your Nextcloud's own sign-in (Murena's included: Sharing), you sign in on that server's page, in your browser; Sioul never sees your password. The server then gives Sioul an app password of its own, which Sioul keeps in your keyring (for the sharing, and for your contacts and calendars there when they use it), sends to that server only, over HTTPS, and to no one else. Your Nextcloud lists it among its devices and sessions, as "Sioul" and your system's name, where you can revoke it; Sioul gives it back to the server itself when you cancel after signing in, or stop sharing (unless your contacts and calendars use it).

Google calendars, contacts and tasks¶

When you add a Google account in Sioul (Accounts ▸ Add an account ▸ Google calendars, contacts and tasks), you sign in on Google's own page, in your browser. Google then asks your permission for these scopes:

If you untick tasks on Google's page, Sioul leaves tasks out, and the rest works.

Signing in with Google for your calendars, contacts and tasks gives Sioul no access to your Gmail, and Sioul's own key never asks for it. If you read Gmail in Sioul, it is added as a mail account of its own, in one of two ways. With an app password you make yourself, as with any mail program. Or, only with a Google key of your own (your own Google Cloud project), by signing in with Google for the mail itself: Google then asks your permission for the scope https://mail.google.com/, which Sioul uses to read that mailbox over IMAP and to send the messages you send over SMTP, as any mail program does. That mail is kept on your device as any account's mail is; its sign-in has a keyring entry of its own, apart from the calendars'; and removing the account gives the access back to Google (unless your calendars use the same key, since Google would end their access too: Sioul then only forgets it).

How Google data is used¶

Only to show your calendars, contacts and tasks in Sioul, on your device, and to write back to your Google account the changes you make there, when you make them. Within Sioul, this data serves the features you see: the agenda, the contacts, the tasks and the plan of your days, reminders before events and dates, and the ties you make between your things.

Google data is not used for advertising, not sold, not used to build profiles, and not used to develop, improve or train artificial intelligence or machine-learning models. Nobody working on Sioul can read it: it never reaches them.

Where Google data is kept¶

• On your device: one file per event, task and contact, in Sioul's data folder (on Linux, ~/.local/share/sioul/calendars/ and ~/.local/share/sioul/contacts/, in a folder named after the account).
• In your own Google account, where it already is.
• The sign-in: the refresh token Google gives, with the client's identifier, as one entry in your system's keyring. The access token stays in memory only, for an hour at most.

Nothing is kept on any server of the developer: there is none.

Sharing of Google data¶

Sioul does not send data received from Google APIs to its developer, or to any third party. That data leaves your device only in these cases, each chosen by you:

1. Back to Google, when you change something in Sioul.
2. When you send something yourself: an e-mail is sent only when you press Send. When you write to the guests of an event, their addresses come from the event.
3. To OpenStreetMap's geocoder, only once you allow it (Place them, on the Contacts page's map, or Place contacts on the map in its settings): your contacts' postal addresses, Google contacts' included, are sent once each to OpenStreetMap's Nominatim service, to find where they are on the map. Nothing else is sent with them.
4. To your other devices, only if you turn on sharing between your devices: what Sioul keeps on this device about your things (for example, which note is tied to which task, or the time noted on a task) travels through a folder of your own sync service, encrypted on your device with your passphrase; that service cannot read it. Your Google events, contacts and tasks themselves travel only by Google.
5. To an AI agent you connect yourself, only if you do (see Using an AI agent): an agent such as Claude Code or Claude Desktop, connected to Sioul on your device, can read what you open to it: the projects you open (each is closed to agents until you open it) and, unless you close them, the things in no project, your phone's messages and calls, papers, your texts only if you allow them, Google calendars, contacts and tasks included; the company behind its model receives what it reads, under your own agreement with that company. Sioul never connects an agent by itself.

Sioul's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

Taking the access back¶

• In Sioul: Accounts ▸ Your accounts, on the Google account's card, Remove. Sioul gives the access back to Google (it revokes the token) and empties its keyring entry.
• At Google: myaccount.google.com/permissions, where you can remove Sioul's access at any time.

Removing the account leaves your Google account itself as it is. The copies already on your device stay in Sioul's data folder until you delete them: on Linux, the folders named after the account in ~/.local/share/sioul/calendars/ and ~/.local/share/sioul/contacts/.

If you use a Google key of your own (your own Google Cloud project, as Sioul allows), all of the above holds the same: the data travels only between your device and Google. Such a key also lets you sign in to Gmail through Google (above).

Microsoft mail¶

When you add an Outlook.com, Hotmail, Live, MSN or Microsoft 365 address in Sioul (Accounts ▸ Add an account ▸ Add a mail account), you sign in on Microsoft's own page, in your browser: Microsoft takes no password from mail programs. Microsoft then asks your permission for these scopes:

Sioul asks nothing more: not your calendars, not your contacts, not your files.

How Microsoft data is used¶

Only to show your mail in Sioul, on your device, and to do on your mailbox what you do in Sioul, when you do it. Within Sioul, it serves the features you see: the Porch, the checks of who sent each message, reminders, the ties you make between your things, and the spam filter you train yourself. Microsoft data is not used for advertising, not sold, not used to build profiles, and not used to develop, improve or train any general artificial-intelligence or machine-learning model. The one thing that learns from it is your own spam filter, on your computer, and only from the personal Microsoft addresses you named by pressing Train now (below); what it learns serves you alone. Nobody working on Sioul can read it: it never reaches them.

Where Microsoft data is kept¶

• On your device: your mail, as any account's, in Sioul's data folder (on Linux, ~/.local/share/sioul/mail/, in a folder named after the account).
• In your own Microsoft mailbox, where it already is.
• The sign-in: the refresh token Microsoft gives, with the application's identifier and your account's directory, in your system's keyring only, split over a few entries when it is too long for one. Microsoft gives a new refresh token each time one is used: Sioul keeps the newest in place of the one before. The access token stays in memory only, about an hour.

Nothing is kept on any server of the developer: there is none.

Sharing of Microsoft data¶

Sioul does not send data received from Microsoft to its developer, or to any third party. That data leaves your device only in these cases, each chosen by you:

1. Back to Microsoft, when you act on your mail, and when you send a message.
2. To your other devices, only if you turn on sharing between your devices: what Sioul keeps about your things, encrypted on your device with your passphrase. Each device fetches the mail itself from Microsoft.
3. To Anthropic, through the AI shield, only for a personal Microsoft address you protect against harassment, and only once you turn on Let the AI read it first and give your own key for Anthropic's API (below, Other data). Never for a work or school Microsoft address: its mail is its organisation's too, and Microsoft's terms ask the organisation's consent before it goes to another company; Sioul does not offer it there, whatever its settings say.
4. To an AI agent you connect yourself, only if you do: a personal Microsoft address's mail as any other's, as far as you open it to the agent. A work or school Microsoft address's mail is kept from agents until you open it in Settings ▸ AI agents, which you should do only if your organisation allows it.

Your own spam filter, on your computer, learns from the mail of a personal Microsoft address only once you have pressed Train now with that address named under it: that press is your consent, for each address named. Sioul keeps, on that computer, the list of the addresses named at your last press, and the filter's later downloads and trainings, by itself once a week or for an AI agent you connect, learn from no Microsoft address outside that list. It never learns from a work or school Microsoft address. What it keeps stays on that computer (below, Other data).

Sioul's use of the Microsoft APIs adheres to the Microsoft APIs Terms of Use: it syncs your mail with your device, and does no more with it than what you choose, as this policy says. Microsoft's own processing of your data is described in the Microsoft Privacy Statement; this policy is no less protective.

Taking Microsoft's access back¶

• In Sioul: Accounts ▸ Your accounts, on the address's card, Remove. Sioul forgets its sign-in on this device, and asks whether to delete the mail it keeps on this device for that account: yes, unless you untick it (its mail folder, what the AI shield kept of it, what the spam filter keeps of it).
• At Microsoft: Microsoft offers apps no way to give an access back, so Sioul stays among the apps you allowed until you remove it there: for a personal account, account.live.com/consent/Manage; for a work or school account, myapps.microsoft.com, or your organisation's administrator. A password changed or reset usually ends Sioul's access too.

Removing the account leaves your mailbox at Microsoft as it is.

Other data¶

Sioul reads and keeps your mail, calendars, contacts, tasks, notes, budgets, papers and the other things you give it, on your device, as described above. Besides your own providers, it reaches other services only for a feature you choose:

• Weather, if you choose a place: Open-Meteo receives that place's coordinates, rounded to two decimals, at most every half hour, or the name of a town you search.
• The map of your contacts, if you allow it: OpenStreetMap's geocoder receives their postal addresses, once each; map images come from OpenStreetMap, or from the source you chose.
• Finding someone's encryption key, when you ask: their domain's Web Key Directory, then keys.openpgp.org, receive the address you write to.
• The AI shield, only for an address you protect against harassment, and only once you turn on Let the AI read it first on its card in Accounts and give your own key for Anthropic's API: every message in that address's inbox that the AI has not read yet, from anyone, those already there when you turn it on included, is sent to Anthropic, the newest first, twenty at a time, to tell its tone and topic. For each, Anthropic receives the subject and the first 4,000 characters of its text, as they are: nothing is masked, so a code, a password or an account number in such a message reaches Anthropic too. A message whose answer comes back malformed is sent again later. The answer (a tone, a topic, one neutral line) stays on your device; what Anthropic does with what it receives falls under your own agreement with Anthropic. To stop it, turn Let the AI read it first off, or choose Forget the key in Accounts. It reads mail only, never Google data, and never the mail of a work or school Microsoft account.
• GitHub, if you turn it on: your issues and pull requests are read with your own token. Nothing is written to GitHub.
• Bitwarden, when you fill a login from your vault: your Bitwarden server, with your account.
• The sites you pin, as any browser: each is also asked for its own icon.
• Antivirus signatures, once a day, only when your system keeps none of its own.

On a phone, if you give Sioul Android's notification access, it reads the notifications of the apps you let it see, on the phone, to hold them until their time; it keeps none of their words and sends nothing of them anywhere (Settings), with one exception, which you choose: if you turn on Messages from your phone in your sharing, the phone sends your other devices the messages its notifications bring, for the apps you choose (its SMS app unless you say otherwise): who wrote, when, and the words, or only who and when. They are encrypted with your passphrase before they leave the phone, pass only through your own sharing folder or server, and are kept a week. A reply you write to one of them on a computer goes to the phone the same way, encrypted, naming the computer that wrote it, and the phone, which takes replies only from a device your sharing counts, hands it to that notification's own Reply; the replies are kept a week, sealed, and what became of each comes back without its words. Never a code, a picture, a blocked sender's message, nor a notification its app keeps secret (What reaches you).

On a phone, if you allow Sioul to read and send texts (Settings ▸ This phone ▸ Texts) and turn on Texts in your sharing, the phone sends your other devices all its texts, with the pictures, sounds and videos of its multimedia messages, encrypted with your passphrase before they leave the phone, and kept encrypted on each device that receives them, as an archive that only grows (a text deleted on your phone stays, marked so); a text you write on a computer travels the same way to the phone, which sends it through your carrier. So do the pictures, videos, sounds and contact cards you attach there, as one multimedia message: a picture is written again on the computer before it leaves, from its pixels alone, without its GPS position, its camera, its time or any other detail of its file, and never under its file's name; an animated GIF keeps its frames alone; a video, a sound or a card goes as it is, with whatever its file holds (Privacy and security). They pass only through your own sharing folder or server, never another service. Sioul never becomes your SMS app, never marks a text as read and never deletes one (Texts).

On a phone, if you make Sioul Android's caller ID & spam app, Android shows it each call's number before the phone rings; Sioul decides there, on the phone, and sends no number to any server: no lookup. The list of the calls it screened goes to your other devices only, encrypted with your passphrase, while your sharing's part Calls is on. It never answers, records or listens to a call (Calls).

Your own spam filter, on a computer: it learns the first time when you ask (Train now), then again by itself once a week, on the computer that trained it, while that computer is plugged in and idle, unless you turn off Train again by itself once a week, when this computer is plugged in and idle. To learn, Sioul reads from your mail provider, without changing anything there, the messages of every folder but the trash, drafts and sent mail (from Gmail's All Mail, only the archived mail that no other folder holds, never your own messages), and keeps on that computer, for each message, its headers, the names and types of its parts and the start of its text, never the attachments themselves, with the language model it learns. To check each sender as it checks the mail it stores, it also reads each message of up to 2 MB whole, in memory only, keeps only the results of the checks, and asks your system's DNS about the senders' domains. What it keeps and the language model stay on that computer, and Sioul sends them nowhere: for training, it talks only to your own mail providers, to read, and to your system's DNS; on a metered connection, or one it cannot tell, training by itself downloads nothing. Only the result, a table of numbers with no word of your mail in plain text, goes to your other devices, encrypted with your passphrase, if you share between your devices, with what you said is spam or not on each device (which message, where and when; never a word of it). If you import outside training material on that computer (sioul spam import: mail labelled elsewhere, its subjects and texts), it stays there, apart from your mail, never shared, until you remove it. Nothing of it goes to the developer or to any other service. If you connect an AI agent yourself, it can run the filter's own tools, which report its numbers and list its worst mistakes by sender and subject, with codes and account numbers masked; the company behind the agent then receives what it reads, unless you keep those tools from it (Using an AI agent). It learns from your mail only: never from data received from Google (Privacy and security). Under Train now, a sentence names the addresses it learns from: pressing it is your consent, for each, as Microsoft's terms ask for a Microsoft address. Sioul keeps the list of the addresses named at your last press, and learns from a Microsoft address, by itself or for an AI agent, only when it is on that list; from a work or school Microsoft address, never.

The complete list, with when each happens: Privacy and security.

Sioul has no analytics, no advertising, no tracking, and no crash reports.

Security¶

Connections to Google and Microsoft use HTTPS. Each sign-in follows the provider's guidance for installed applications: its page opens in your browser, and Sioul receives the answer on your own device only (a loopback address), checked with PKCE and a state value. With Microsoft, Sioul holds no secret at all, and its tokens go to Microsoft's sign-in service and to Microsoft's own mail servers, named exactly, never elsewhere. A Nextcloud's sign-in follows its own login flow: its page opens in your browser, and Sioul asks that server alone for the result; an answer that names another server is refused, and nothing of it is kept. Passwords and tokens are kept in your system's keyring. What you share between your devices is encrypted on your device before it leaves it.

This website¶

This website has no analytics, no advertising and no cookies, and loads nothing from other sites. It is hosted by GitHub Pages, which keeps its own server logs under GitHub's privacy statement.

Changes to this policy¶

Any change is published on this page, with a new date. The history of this page is public, in Sioul's repository.

Contact¶

Questions about this policy, or about your data: GitHub issues.

The developer holds none of your data, so there is nothing of yours to ask the developer for, correct or delete: everything Sioul keeps is on your device and in your own accounts, where you can read it, change it or delete it.