A fast, native mail client for GNOME.
Mailbox is a GTK4 email client written in Go. Mail is stored in a local database, so search is instant and reading works offline. Gmail connects through its own API; Yahoo, iCloud, Fastmail, Outlook, and any other provider connect over IMAP. If you give it an AI model — any OpenAI-compatible or Anthropic endpoint — it will sort your inbox, summarize threads, draft replies, and translate mail. The AI is optional; everything else works without it.
It is also careful with your mail: tracking pixels are stripped before a message is rendered, email can never run scripts, senders that fail authentication are flagged, and passwords and tokens are kept in the system keyring.
Triage
- The inbox is sorted into action tags: Needs reply, Receipt, Travel, Newsletter, and so on.
- Threads can be snoozed with a preset, a date from a calendar, or a moment the AI suggests after reading the mail — the day before a deadline, an hour before a meeting.
- Unsubscribe works in one click, and a subscriptions dialog lists every mailing list you're on, sorted by how much each sender mails you.
- Every action has a keyboard shortcut, and all of them can be rebound.
Reading and writing
- A conversation renders as a single thread, with quoted history folded away.
- Meeting invites appear as a card with Accept, Maybe, and Decline buttons.
- Thread summaries, drafted replies, translation, and proofreading are a click away.
- A sent message can be undone for a few seconds; failed sends are queued and retried up to five times, then remain in the outbox for manual retry.
- New-mail notifications appear immediately with the message snippet and use a cached one-line AI gist when one is already available.
Accounts
- Gmail uses its native API, so labels, server-side search, and sync behave the way Gmail expects.
- IMAP accounts get new mail pushed as it arrives when the server supports it, and are polled otherwise.
- Any number of accounts can run side by side, each with its own name and signature.
sudo dnf install golang gtk4-devel libadwaita-devel webkitgtk6.0-devel libsoup3-devel libsecret-devel
make build
./bin/mailboxThe app opens to a welcome screen, and Add account… takes it from there. IMAP providers need only an app password; Gmail and Outlook need a one-time client setup. docs/SETUP.md walks through every option, including turning on the AI.
The AI runs against whatever model you point it at, and the difference between models is large: across seven local models the inbox tagging ranged from 34% to 96% correct, and the best one was neither the biggest nor the slowest.
If you want to try a model on your own hardware, bench/ has a benchmark that
scores tagging, summaries, drafts and translation, and measures real memory and
speed. Name a model and it is compared against the one you're running:
cd bench && python3 bench_models.py Qwen3.5-9B-GGUFdocs/BENCHMARK.md explains what the numbers mean and which models have been measured so far.