Data Handling
How Meridian handles, processes, and protects your data
Meridian is designed so that your data stays yours. This page explains how your data is processed, stored, and managed throughout the system.
Zero-Knowledge Architecture
Meridian’s server is designed so that a server compromise does not expose synced user content. The relay stores encrypted payloads it cannot read and has no server-side content-decryption keys. Authentication and routing still require limited metadata such as your login email, entity identifiers, and timestamps.
On-Device Processing
Integration processing happens entirely on your device. This includes:
- Fetching emails from your providers
- Parsing calendar events
- Refreshing OAuth tokens directly on the client when the provider allows it
The server acts as a sync relay, not a data processor. It passes encrypted data between your devices without inspecting or transforming it.
Your Data Rights
You have full control over your data at all times:
- Access – Export your data at any time from within the app.
- Disconnect – Remove any connected account and its associated data.
- Delete – Permanently delete your account and all associated data from Meridian’s servers.
Data Retention
Meridian retains encrypted sync history and verified encrypted checkpoints as needed to bring devices up to date and support portable exports. Pruning is deliberately fail-closed: history is removed only when the checkpoint and active-device safety conditions are satisfied. Meridian does not promise a fixed retention window for sync history.
When you delete your account, all data is permanently removed from Meridian’s servers. This action is irreversible.
Third-Party Access
Meridian uses OAuth 2.0 to connect to your email, calendar, and contact providers. This means:
- Meridian never asks for your primary Google or Microsoft password. iCloud and Fastmail use revocable app-specific credentials.
- Provider tokens and app-specific credentials are encrypted on your device. Ciphertext may be mirrored through Meridian for another authorized device, but the server cannot decrypt or use it.
- You can revoke Meridian’s access from your provider’s settings at any time.
Children’s Privacy
Meridian is designed for users 13 years of age and older. We do not knowingly collect data from children under 13.
AI & Privacy
Meridian’s on-device AI model runs entirely locally on your Mac. Your data is never sent to cloud AI services, and the model is not trained on your data.
AI-generated embeddings used for semantic search stay in a per-device local index and are not synced. Synced user content remains protected as described in the Encryption page.