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Check out the answers to the most frequently asked questions about Relay. If you weren’t able to find an answer to your question, connect with the team on Discord or GitHub.
Building apps that read, classify, and react to e-mail is still painful—rate-limited Gmail APIs or raw IMAP sockets. Relay gives you a modern CLI and library to manage emails locally, with clean Python APIs for building email-powered applications.
Install the CLI with pip install relaycli, then run relay accounts add to connect your first email account. The quickstart guide walks you through the entire setup in under 5 minutes.
Any inbox that speaks IMAP/SMTP: Gmail, Outlook, Yahoo, FastMail, or your own Dovecot/Postfix server. The same CLI commands work across all of them.
All credentials are stored locally on your machine, encrypted using your OS keychain (macOS Keychain, Windows Credential Manager, Linux Secret Service). Nothing is sent to external servers.
  • Gmail API → Google-only, strict quotas, complex OAuth flows.
  • SaaS email APIs → cloud-locked, proprietary, often read-only, expensive.
  • Relay → open-source, runs locally, works with any IMAP provider, full read/write access, free.
  • Email automation scripts and bots
  • Custom email clients or dashboards
  • Smart auto-responders and filters
  • Integration with other business tools
  • Voice-controlled email interfaces
If it involves reading, searching, or managing emails, you can build it with Relay.
Yes! Connect unlimited email accounts with relay accounts add and switch between them or manage them all simultaneously. Each account gets its own secure credential storage.
Yes! The core Relay CLI and library are completely free and open-source. Optional cloud services may be introduced in the future, but the local functionality will always remain free.