xmatic

Native Matrix client built on matrix-rust-sdk with a Silica UI.

FEATURES

- Sliding sync, end-to-end encryption, cross-signing, device verification (both directions), key backup and recovery
- Rooms, spaces (nested), direct chats, threads (answer in one or start one), room directory search
- Create rooms, invite, leave; member list and member profiles with moderation
- Send, edit, delete, reply, pagination in encrypted rooms
- Formatted messages: bold, italic, code, quotes, lists and links render as themselves
- Pinned messages, favourites, low priority, per-room mute, ignored users
- A room opens where you stopped reading, and says who has read what
- Four coloured lines say how safe the device is: backup, recovery, cross-signing, local storage
- Reactions from an emoji picker whose first tab you fill yourself
- Pictures, files, sharing (also as share target from Gallery / file manager)
- Voice messages; voice and video calls (classic 1:1 VoIP; MatrixRTC-only clients cannot be called)
- Notifications, offline send queue, encrypted local storage
- OAuth (MAS) login, device-code login, password login
- 29 interface languages, switchable in the app

LANGUAGES

The interface is available in the 24 official languages of the European Union
plus Russian, Norwegian, Icelandic, Simplified Chinese and Hindi. Norwegian was contributed by a Norwegian
speaker and German is the project language; the rest are machine translations,
usable but unchecked. Account has a language setting of its own, English
included, so there is always a way back out of one. A change applies at the
next start.

Corrections are welcome at the GitHub repository below - the file to edit is
translations/harbour-xmatic-<language>.ts, and translations/STATUS.md says
which languages have been read by a native speaker.

LOCAL STORAGE

Session tokens and the message database are encrypted with a key from Sailfish
Secrets.

Some Sailfish images ship only the client library of that key service and not
the service itself. On such a device xmatic no longer creates an unencrypted
database quietly: it says what is missing, gives the command to install it and
a command to check the result with, and offers to continue without encryption
as an explicit choice. The package also requires the service, so on most
devices this never comes up.

An installation that already holds data is never blocked - that would strand
its room keys. Where a database simply predates the key, the encryption page
offers to re-create it encrypted, which costs one sign-out and your recovery
key.

How safe the device is stands in four coloured lines - backup, recovery,
cross-signing, local storage. Green is in order, orange is something you can
put right, red is something the system does not offer. If anything is not
green, the app says so once after starting, with the action that fits and
"later" always available. When everything is green you never see any of it.

WHY IS THE PACKAGE SO BIG?

The app ships the complete Matrix stack statically: matrix-rust-sdk, E2EE
(vodozemac), sliding sync, rustls, its own HTTP runtime and a bundled SQLite.
None of that exists as a system library on Sailfish OS, and Qt 5.6 is too old
for the C++ alternatives - which is exactly why the protocol core is written in
Rust. Installed size ~51 MB (Element X, same SDK: ~100 MB), RPM ~16 MB.

NO BACKGROUND DAEMON

Messages arrive while the app is running (the cover is enough). Like other
daemonless messengers on this platform, a closed app does not receive.

ARCHITECTURES

aarch64 (Sailfish OS 5.0+), armv7hl (Sailfish OS 4.6+).

REQUIREMENTS

xmatic syncs over simplified sliding sync (MSC4186), the same mechanism
Element X uses. Your homeserver must support it. If it does not, sign-in
works but no rooms load and the app keeps showing "Offline".

How to check your server: open this address in a browser

https://YOUR-SERVER/_matrix/client/versions

and look for this line:

"org.matrix.simplified_msc3575": true

If it is missing, xmatic cannot load your rooms from that server.

Sign-in methods supported: OAuth 2.0 / Matrix Authentication Service,
device code ("Sign in on another device"), and username plus password on
servers without OAuth.

The classic SSO redirect sign-in (SAML, CAS) is not supported.

Written with Claude Code (Anthropic), icons included; the protocol core is upstream matrix-rust-sdk.

Source, issues, releases:
https://github.com/JimKnopfIoT/harbour-xmatic