simplemailclient

A small terminal mail client written in Rust. It sends mail over SMTP, fetches over IMAP, and gives you a split-pane TUI for reading, replying, and composing.

The installed binary is named mailrs (avoids clashing with the standard Unix mail command).

Features

• TUI inbox — folders (Inbox / Sent / Starred / Trash), a message list, and a reading pane, navigable with Tab / arrow keys and j / k.
• Compose & reply in-app: To / Body / Attach fields, Ctrl+S to send, Esc to cancel.
• File attachments — attach any file type up to 25 MB (zip, images, PDFs, text, …). Each file is sent as its own MIME part, fully separate from the message body. On received mail, attachments are listed below the body; focus the reading pane, pick one with ↑/↓, press Enter to preview text files inline, or Ctrl+A to save to your Downloads folder.
• Inline text preview — Enter on any text attachment (.txt, .md, .json, .csv, source files, …) opens a scrollable full-screen viewer. Esc to close.
• Real trash — d moves the message locally and copies it to the configured trash folder on the IMAP server, then expunges it from the inbox so it never comes back on re-sync.
• New-mail bell — a terminal beep fires when a sync brings in unread mail.
• Deduplication — messages are keyed by their RFC 2822 Message-ID; a message you've already seen is never re-delivered on sync.
• Auto-sync every 10 seconds while idle, plus on-demand sync with S. Fetches up to the last 50 messages.
• Contacts — auto-collected from every address you send to or receive from. Press ? to open the contacts panel (it gets focus automatically), where you can add entries manually, delete them, and set a short nickname (alias). In the compose To field, address someone by their numeric ID, nickname, bare username, or full address.

Install

cargo install simplemailclient

Configuration

On first run a starter config is written to your config directory (~/.config/mail-rs/config.toml on Linux/macOS, %APPDATA%\mail-rs\config.toml on Windows). Fill in your SMTP/IMAP details:

identity     = "you@gmail.com"
display_name = "Your Name"
domain       = "gmail.com"

[smtp]
host     = "smtp.gmail.com"
port     = 587
username = "you@gmail.com"
password = "your-app-password"   # use an App Password, not your login password
tls      = true

[imap]
host          = "imap.gmail.com"
port          = 993
username      = "you@gmail.com"
password      = "your-app-password"
tls           = true
inbox_folder  = "INBOX"
trash_folder  = "[Gmail]/Trash"  # Gmail; other providers: "Trash" or "Deleted"

Gmail users: trash_folder must be [Gmail]/Trash.
Other providers: try Trash (the default) or Deleted.

Usage

mailrs                      # launch the interactive TUI
mailrs send <username|id>   # compose and send from the command line
mailrs inbox                # list inbox messages
mailrs read <index>         # read a message by index
mailrs sync                 # fetch new mail via IMAP

TUI keys

Contacts panel (?)

Pressing ? opens the panel and immediately focuses it — no extra Tab needed.

Compose modal

Tab cycles To → Body → Attach → Body.

The To field accepts any of:

• a full address — alice@example.com
• a bare username — alice (appended with your configured domain)
• a numeric contact ID — 3
• a nickname — ally (if set for that contact)

In the Attach field, type a file path and press Enter to queue it. Backspace on an empty input removes the last queued file. Ctrl+S sends; Esc cancels.

Attachment viewer

Enter on a selected attachment (reading pane) opens an inline viewer for any UTF-8 text file. Use ↑↓ / j / k to scroll, PgUp / PgDn for larger jumps, and Esc or q to close. Binary files (images, zips, etc.) show an error and prompt you to use Ctrl+A to save instead.

Data

Mail and contacts are stored locally:

Configuration lives in:

License

MIT