Concordance Privacy Policy
This policy explains what data Concordance collects, how it is used, stored, shared and deleted, and how Concordance accesses, uses, stores and shares Google user data. Last updated: October 5, 2026. Version française : règles de confidentialité, qui font foi.
Who we are
Concordance (concordance.duperret.eu) is a personal study planner, operated on a non-commercial basis and open by invitation to a small number of people. It helps users plan long-term work — textbooks to read, courses to attend, practice tests — and measures it in hours. Data controller: Sacha Duperret. Contact: concordance@duperret.eu.
Data we collect
- Email address — required to create an account and sign in, with Google or with a one-time link sent by email.
- Time zone — to compute your days and weeks correctly.
- Study data you enter or import — goals, textbooks, chapters, courses, sessions, reviews, practice tests, reading progress and time spent.
- Technical data — a session cookie, calendar feed and push-notification subscriptions you create, a log of processing operations on your account (kept ninety days), and server logs, which include your IP address (no fixed purge date).
We do not collect passwords, payment data, contacts, location, or analytics data, and we use no advertising or tracking cookies.
How we use data
Data is used solely to provide the service to you: show what to study each day, schedule reviews, track progress, send the emails you opt into, and publish your study slots to your calendar if you ask. It is never sold, never used for advertising, never used to build profiles, and never aggregated across accounts.
Google user data
Signing in with Google requests only openid and
https://www.googleapis.com/auth/userinfo.email: Concordance receives your verified
email address and uses it only to identify your account. Concordance does not read or write any
other data at Google (no calendar, spreadsheet or Drive access) and stores no Google access
token: your course calendar is followed through its iCal address, and a spreadsheet through a
file you upload.
Google user data is stored in your account only, isolated from other accounts, and used only for the features above. It is not sold (including to data brokers or information resellers), not transferred to third parties, not used for advertising, not used to determine credit-worthiness or for lending purposes, not used to train artificial intelligence or machine learning models, and not read by humans except with your explicit consent for support, for security purposes, or to comply with the law. Concordance’s use and transfer to any other app of information received from Google APIs will adhere to the Google API Services User Data Policy, including the Limited Use requirements.
Sharing
Data is shared only with the service providers needed to run Concordance: the hosting provider (Infomaniak Network SA), Google (sign-in), Resend (sending the emails you request), and your browser’s push service (notifications you enable). Data is hosted Suisse.
Storage and security
Data is encrypted in transit. Calendar feed addresses and backups are encrypted at rest. Each account is isolated at the database level, so one account cannot read another’s data. Sign-in links and invitation tokens are stored only as hashes.
Retention and deletion
Data is kept while your account exists. You can export all your data at any time (Mon compte ▸ Emporter mes données, “My account ▸ Export my data”) and delete your account (Mon compte ▸ Supprimer mon compte, “My account ▸ Delete my account”): it is erased after a seven-day grace period, and removed from encrypted backups within thirty days. You may also request access, correction or deletion by email at concordance@duperret.eu, and lodge a complaint with the French data protection authority (CNIL).
Changes to this policy
The date of the last revision is shown at the top of this policy. Any change to how your data, including Google user data, is collected, used or shared is notified to you by email before it takes effect. Any new use of Google user data requires your consent first.