Mailbrus

Fast mail client with Vim-inspired hotkeys, plain-text-first reading, and offline-capable PWA support.

🚧 WIP — This is early-stage software. Mail sync and sending are not yet implemented.

Screenshots

Features

• Keyboard-first UI — global hotkeys, leader-key sequences, an Esc back-stack, and a ⌘K command palette.
• Vimium-style link hints — f overlays single-letter badges on visible rows; press a letter to jump.
• Fast notmuch-backed search — full notmuch query syntax with paginated results.
• Reader + paginated list — deep-linkable URLs (/folder/:id, /folder/:id/message/:id, /search?q=…), browser back/forward, reload-safe.
• Attachments — HTML body parts and binary attachments surfaced uniformly.
• PWA — installable manifest, offline app shell, Background Sync outbox for offline send, Web Push for new mail, app-icon unread badge.
• CLI — mailbrus message search / message read with text, json, and toon output formats.
• Desktop shell — same SPA wrapped in a Tauri window with a bundled mailbrus-server sidecar.

Architecture

flowchart LR
  user(["User"])

  subgraph frontend["Frontend (TypeScript)"]
    spa["SvelteKit SPA<br/>+ Service Worker (PWA)"]
  end

  tauri["src-tauri<br/>desktop shell"]
  cli["mailbrus-cli"]

  subgraph rust["Rust workspace"]
    server["mailbrus-server<br/>axum HTTP + JSON API"]
    core["mailbrus-core<br/>Maildir / notmuch / SMTP"]
  end

  store[("Maildir + notmuch<br/>on disk")]

  user --> spa
  user --> tauri
  user --> cli
  tauri -- embeds --> spa
  tauri -. spawns sidecar .-> server
  spa -- HTTP/JSON --> server
  server --> core
  cli --> core
  core --> store

The SPA is the only UI; it runs either in a browser as a PWA or inside a Tauri window where the desktop shell spawns mailbrus-server as a sidecar. The server and CLI both go through mailbrus-core, which talks to a local Maildir indexed by notmuch.

Dependencies

• Pimalaya — the heart of the mail stack. mailbrus-core builds on the excellent io-email and io-maildir coroutine libraries; SMTP sending is planned on io-smtp. Huge thanks to the Pimalaya project.
• notmuch — fast, read-only indexed message search via the notmuch Rust crate.
• Rust — workspace of mailbrus-core, mailbrus-cli, mailbrus-server, and src-tauri. Server uses axum on tokio; messages are parsed with mail-parser.
• Svelte 5 + SvelteKit — the SPA, styled with Tailwind CSS v4 and bits-ui primitives.
• Tauri 2 — the desktop shell.
• Playwright — end-to-end test runner; tests run inside a Nix devShell.

End-to-End Tests

Mailbrus ships a hermetic Playwright suite that drives the real SPA against a real mailbrus-server backed by a real notmuch index — one freshly cloned mailbox and its own server per test, with guaranteed teardown. Nothing is mocked: every test exercises the browser → HTTP → notmuch → Maildir path end to end.

nix develop          # notmuch + Playwright browsers
deno install         # hydrate node_modules
deno task test:e2e   # headless run
deno task e2e:ui     # interactive UI mode

See docs/e2e-testing.md for the full architecture, fixture model, and trace-debugging workflow.

Installation

Requires Nix with flakes enabled.

# Run directly (ephemeral)
nix run github:antono/mailbrus

# Install to your profile
nix profile install github:antono/mailbrus
mailbrus --help

See docs/development.md for server usage, CLI flags, and debug logging.