Guides

Write and format emails, choose a sending provider, and run Mailfire reliably from scripts and cron.

Each guide covers one task from start to finish. For every flag and setting in one place, see the Reference.

Choose a body format, supply the body from stdin, a file, or the command line, add attachments, and address recipients.

Write rich emails in Markdown, with tables, GitHub-style alerts, and local images that are attached and shown inline.

Choose one of four built-in email templates, or export and customize them, or write your own.

Render the exact HTML body of an email to a file, without credentials, recipients, or network access.

The default provider. Send through the Mailgun HTTP API with an API key and a verified sending domain.

Send through any email provider's submission server or a local relay, with implicit TLS, STARTTLS, or an explicit plaintext relay.

Send through your Gmail or Google Workspace account with a one-time browser sign-in and send-only access.

When sending fails temporarily, Mailfire stores the message and mailfire resend retries it later with backoff.

Send a repeated monitoring alert only once per cooldown with --dedup-key, across sends and retries.

Use Mailfire from shell scripts, cron, and CI with stable exit codes, JSON output, environment configuration, and a send log.

Edit this page on GitHub Last updated October 18, 2026