Fastmail · JMAP protocol · privacy-first

Fastmail email triage.
Native JMAP speed meets AI.

Fastmail users choose privacy and performance. Mailtwine is the only AI email triage platform built with native JMAP integration — delivering instant event synchronization, zero-lag labels, prioritized queues, and grounded reply drafts without clunky IMAP polling.

Start free beta How triage works →

// NATIVE JMAP API · ZERO POLLING LAG · PRIVACY-FIRST · ZERO MODEL TRAINING

Works with your existing email

Keep your mailbox. Get help with the work.

Mailtwine is the underdog working behind the accounts you already use. No new address. No migration. No swapping one inbox for another. It sorts, drafts, routes, and follows up in the background, then asks for attention only when a decision still needs you.

Connect Google Workspace through tenant-owned Google OAuth or keyless service-account domain-wide delegation, Outlook.com and Microsoft 365 through Microsoft OAuth, Fastmail through JMAP, Helpmonks through its native API, or any standard IMAP mailbox with SMTP for sending. MCP-compatible clients connect over OAuth for mail search, summaries, draft suggestions, routing, and approval review.

Google OAuth Keyless service accounts Microsoft OAuth Fastmail JMAP Helpmonks IMAP + SMTP MCP clients

AI assistant for Gmail & Workspace → AI assistant for Outlook →

Modern Architecture

Why native JMAP makes AI email triage radically better

Most AI email assistants only support Gmail and Outlook, forcing other mailboxes through dated, inefficient IMAP connections that poll servers every few minutes and frequently desync. Fastmail co-created JMAP (JSON Meta Application Protocol) to replace IMAP with a lightweight, modern, push-driven standard.

Mailtwine speaks native JMAP. When an email reaches your Fastmail account, Mailtwine receives an instant JSON push event, triages the message, applies labels, and drafts a contextual response within milliseconds. Your inbox is already triaged by the time you open your browser.

Triage softwareAll featuresOpen source roadmap
JMAP Integration

Keep your trusted Fastmail setup. Lose the inbox sorting.

You don’t need to abandon Fastmail for bloated proprietary email clients to get cutting-edge AI assistance. Connect your Fastmail mailbox via API token and gain access to automated prioritization, SLA flags, thread digests, and review-ready drafts.

Scoped API Tokens Sub-Second Push No Password Sharing Label Sync Draft Queue
ACTUAL PRODUCT
mailtwine — fastmail triage queue
Mailtwine triage queue with Fastmail JMAP synchronized threads
FAQ

Fastmail & JMAP triage, answered

How does Mailtwine connect to Fastmail? +
Mailtwine connects directly through Fastmail's native JMAP API using a scoped API token. You never share your account master password with Mailtwine, and you can revoke the token at any time in your Fastmail security settings.
Why is JMAP better than IMAP for AI email triage? +
JMAP (JSON Meta Application Protocol) is a modern, open standard designed for mobile and web efficiency. Unlike legacy IMAP polling which drains battery and lags behind incoming mail, JMAP pushes updates instantly with structured JSON payloads, allowing Mailtwine to triage emails within milliseconds of delivery.
Does Mailtwine replace the Fastmail web or mobile app? +
No. You continue using Fastmail's web client and mobile apps as your daily email reader. Mailtwine acts as an intelligent operating layer in the background, labeling messages, organizing priorities, and preparing draft replies for your review.
Is my Fastmail email data used to train AI models? +
Never. Mailtwine has a strict privacy policy: your email content, metadata, contacts, and drafts are never used to train foundation or public AI models.
FREE DURING BETA UNLIMITED ACCESS Fastmail triage

Triage your Fastmail inbox with AI

Try Mailtwine free during public beta and experience the speed of native JMAP email triage.

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