Katna · free software for Linux
A fast, modern mail appfor the Linux desktop
Katna Mail, Katna Calendar and a small background service, written in Rust and made to feel at home on KDE Plasma and GNOME. An alternative to KDE PIM, free under the GPL.
Early development. Katna Mail is used every day on real accounts, and a prebuilt Arch Linux package follows every change.
A personal project
Inspired by
Katna Mail is not trying to be unique or revolutionary. It is a very personal project: the mail client its author wanted on their own Linux desktop.
Its features and look are openly borrowed from the mail apps they love, mainly Gmail, Mailspring and Thunderbird, and rebuilt in Rust with Katna's own name and icons.
Katna has only been possible because of how far large language models have come. They turned a full mail client, long the work of a whole team, into something one person can build with care. Every screen is still designed, checked pixel by pixel and used every day by its author, on a real desktop with real mail.
What it is good at
Four things Katna Mail cares about more than anything else.
Instant search
Typo-tolerant full-text search over very large mailboxes. Across the 517,000 messages of the Enron corpus, a query takes 2.4 ms at the median and 9.7 ms at p99.
Works when the window is closed
A small background service syncs, notifies and sends scheduled mail, from a binary under 20 MB.
Feels native
System colours and accent, a tray icon with an unread badge, the KDE global menu, desktop notifications you can act on, and your KDE user picture as your own.
Local-first and private
Your mail stays on your machine, remote content is blocked by default, passwords live in your keyring, and TLS is pure Rust.
One app for every screen size
Desktop, tablet and phone layouts in one app, in light and dark. The pictures below follow this site's own light or dark theme.
Katna Mail today
What the current build does, on real accounts.
Accounts
IMAP (IDLE, QRESYNC, labels), POP3 and SMTP, with server autodiscovery. Gmail categories, Important and duplicate copies are handled.
List and reader
Conversations, category tabs, stars, Important, pins, attachment chips, hover actions, Undo toasts, and a clean reading pane with HTML mail, dark mode included.
Compose
Rich text, signatures, inline reply, a pop-out window, scheduled send and undo send.
Encrypted mail
OpenPGP and S/MIME through your own GnuPG.
Attachments
Previews on cards, a built-in viewer, Save all, and Open with any installed app, with a default app per file type.
Your desktop
Tray icon, unread badge, global menu, notifications with Reply all, Mark read and Archive, light and dark themes, and an optional own window frame with blur.
Any screen size
Desktop, tablet and phone layouts in one app.
Settings
Accounts, signatures, keyboard shortcuts, default apps and more, plus a short onboarding for new users.
katnactl
Add accounts and drive the background service from a terminal.
Coming next
Katna Calendar (CalDAV, with events in the Plasma clock), Contacts, Tasks, Notes and Feeds are planned. They already have a place in the app, marked coming soon.
Install on Arch Linux
Every change to Katna is built into an Arch Linux package and published as the arch-latest pre-release, which is also a pacman repository.
- 01
Add the repository
Add these lines to /etc/pacman.conf.
[katna] SigLevel = Optional TrustAll Server = https://github.com/QuakeString/katna/releases/download/arch-latest - 02
Install and start
Install the package, then start the background service now and at every login.
sudo pacman -Syu katna-git systemctl --user enable --now katna-daemon - 03
Update later
Update with the rest of your system, then restart the service.
sudo pacman -Syu systemctl --user restart katna-daemon
The package is x86_64 only and not signed yet. Passwords are kept in the Secret Service, so GNOME Keyring, KWallet or KeePassXC must be running.
Other distributions
Flatpak, .deb, .rpm and more are planned. Until then, Katna builds from source with the latest stable Rust.
Built on the shoulders of giants
Katna would not exist without these projects and the people behind them.
GPUI and Zed (opens in a new tab)
Katna Mail's whole interface is built on GPUI, the fast, GPU-accelerated UI framework that Zed Industries made for the Zed editor. Every pixel, animation and window you see is drawn by it. Thank you, Zed team, for building it in the open.
Pimalaya (opens in a new tab)
The mail protocols under the hood. io-imap, io-smtp and io-sasl speak to your mail servers, on top of imap-codec for IMAP parsing.
KDE (opens in a new tab)
Plasma is the desktop Katna feels most at home on, and KDE's own PIM suite inspired it.
Rust (opens in a new tab)
Makes a fast and safe mail client a joy to write. Katna has no unsafe code.
And the libraries underneath
- Tantivy (opens in a new tab) · search
- rusqlite (opens in a new tab) · storage
- rustls (opens in a new tab) · TLS
- mail-parser (opens in a new tab) · MIME
- html5ever (opens in a new tab) · HTML mail
- zbus and ashpd (opens in a new tab) · D-Bus and portals
- oo7 (opens in a new tab) · Secret Service
- hayro and krilla (opens in a new tab) · PDF view and print
- calamine (opens in a new tab) · spreadsheets
- resvg (opens in a new tab) · SVG
- jiff (opens in a new tab) · dates and time zones
- spellbook (opens in a new tab) · spell checking
- smol (opens in a new tab) · async
- SQLite (opens in a new tab) · stores your mail
CREDITS.md lists every library Katna uses, with its authors, licence and link. Read CREDITS.md (opens in a new tab)
With love for Linux and the free software community that builds it.
Support KDE
KDE builds the desktop Katna feels most at home on, and it is made by volunteers and funded by people like you. If you enjoy Plasma or KDE's apps, please consider donating to KDE.
Support and follow
Katna is free software, built in the open. If it helps you, a coffee keeps it going.
Follow the author, Mozammel
Katna is licensed under the GNU General Public License, version 3 or later (GPL-3.0-or-later).