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Privacy Policy

Last updated: February 21, 2026

Introduction

ChainLog is a bike maintenance log that uses your data from sports platforms (Strava, Geovelo) to track mileage and maintenance for your bikes. This policy explains what data we collect and how we use it.

Data collected

When you use ChainLog, we collect the following data via the APIs of connected platforms (Strava, Geovelo):

  • User profile (first name, last name, profile picture)
  • List of your bikes (name, brand, model, mileage)
  • Cycling activities (date, distance, elevation, duration, bike used)
  • Email address (if you choose to provide it for alerts)

How we use your data

Your data is used exclusively for:

  • Syncing your mileage from connected platforms
  • Automatically receiving your new activities, edits, and deletions from Strava in real time
  • Calculating component wear and triggering maintenance alerts
  • Sending email notifications (if enabled)
  • Generating maintenance certificates for resale

Third-party services

ChainLog uses the following third-party services:

  • Strava — to import your cycling data
  • Resend — for sending notification emails
  • Neon (PostgreSQL) — for data storage
  • Vercel — for application hosting

Legal basis for processing

The processing of your data is based on the following legal grounds:

  • Performance of a contract — to provide the service (data import, mileage tracking, alerts)
  • Consent — for sending email notifications (can be withdrawn at any time)
  • Legitimate interest — for service improvement and abuse prevention

Cookies and sessions

ChainLog uses a session cookie (Auth.js) to keep you logged in. No tracking or advertising cookies are used.

Data retention

Your data is retained as long as your account is active. You can request deletion of your account and all your data at any time.

Your rights (GDPR)

Under the GDPR, you have the following rights:

  • Right of access — view the data we hold about you
  • Right of rectification — correct your personal data
  • Right of erasure — request deletion of your account and data
  • Right to data portability — receive your data in a structured format

Contact

For any questions regarding your personal data, please visit our support page.