# Komai

Komai is our own desktop Matrix client. We host [Matrix](https://matrix.org/) servers for a living, so we spend our days watching what chat apps do to the people using them. We built the one we wanted to use: native, fast, and honest about what it can’t do yet.

It’s built in Rust, C++, and QML, no Electron, so it opens fast and your laptop fan stays quiet. It’s free software (GPL-3.0-or-later), no CLA, no contributor gatekeeping, and it’s the client we use ourselves every day.

![The Komai main chat window: a room list on the left, a message timeline in the middle, and the composer at the bottom](https://etke.cc/img/komai/main-view.webp)

[Download Komai](https://github.com/etkecc/komai/releases/latest) [View on GitHub](https://github.com/etkecc/komai)

## Why we built our own

Almost a decade ago we rewrote how Matrix self-hosting works with [matrix-docker-ansible-deploy](https://github.com/spantaleev/matrix-docker-ansible-deploy/). That solved servers. It never solved the client problem: people kept bouncing off the apps, and a chat app that loses people is worse than no chat app.

So we forked [nheko](https://nheko.im/nheko-reborn/nheko), the closest thing to a native client worth building on, and started patching. A hundred patches later we stopped pretending and made it ours. We tore out the old crypto libraries and rebuilt the core on the Rust [matrix-sdk](https://github.com/matrix-org/matrix-rust-sdk), because that’s where the whole ecosystem is heading. The full story is on [our blog](https://etke.cc/blog/introducing-komai/).

Many of your apps are secretly Chromium. Komai isn’t. That’s the whole pitch in one line.

## The features the others won’t touch

Most Matrix clients ship the same table stakes and call it done. Komai keeps going. These are the things we built because nobody else would.

### Room tabs, with pinning

Most chat apps give you one conversation at a time and make you dig through a room list. Komai has browser-style tabs across the top: open the rooms you live in, pin the ones that matter, and they’re right where you left them after a restart. Almost no other Matrix client does this, and it’s the first thing you miss when you switch back.

![A row of pinned room tabs across the top of the Komai window](https://etke.cc/img/komai/tabs.webp)

### Selecting messages like files

Drag across a run of messages, Ctrl-click a few, or grab them from the keyboard, then copy, reply, forward, or delete the lot in one move. The clean way to tidy a channel or lift a stack of quotes from a busy room, without death by right-click.

![Several messages highlighted at once in the Komai timeline with a batch-action toolbar](https://etke.cc/img/komai/timeline-selection-mode.webp)

### Automations for the rest of your machine

Komai speaks [MCP](https://github.com/etkecc/komai/blob/main/docs/user-guide/features/automations/mcp.md), ships [CLI commands](https://github.com/etkecc/komai/blob/main/docs/user-guide/features/automations/cli.md), and answers on [D-Bus](https://github.com/etkecc/komai/blob/main/docs/user-guide/features/automations/dbus.md), so scripts and other programs on your machine can read and send messages through it. That’s a real script in the screenshot, posting into a room over the API.

![An external tool sending messages through Komai over its automation interface](https://etke.cc/img/komai/automations-mcp-codex.webp)

## Calls, and rooms worth joining

### Voice and video, built in

[Element Call](https://github.com/element-hq/element-call) is wired right into Komai: end-to-end encrypted [MatrixRTC](https://github.com/matrix-org/matrix-spec-proposals/pull/4143) calls, one-on-one or a whole room piling in, with no separate app to launch. The older [legacy 1:1 calls](https://github.com/etkecc/komai/blob/main/docs/user-guide/features/legacy-calls.md) from nheko are still there, off by default. On Windows and macOS the build ships Element Call but not that legacy stack.

> **Calls need a server that supports them.** Your homeserver has to run a [MatrixRTC backend](https://etke.cc/help/extras/matrix-rtc/) (LiveKit plus lk-jwt-service), or the call screen loads and never connects. On an etke.cc server, [Matrix RTC](https://etke.cc/help/extras/matrix-rtc/) is an add-on, and once it’s on, calls work in any room with nothing to enable.

![An Element Call voice and video call running inside Komai](https://etke.cc/img/komai/element-call.webp)

### A room directory that finds your people

The [room directory](https://github.com/etkecc/komai/blob/main/docs/user-guide/features/room-directory.md) searches the wider Matrix network through [matrixrooms.info](https://matrixrooms.info/), the public room index we build and run. Filter by name, topic, or how large a room is, and find your people instead of trading room addresses in a DM.

![Komai room directory searching public Matrix rooms through matrixrooms.info](https://etke.cc/img/komai/room-directory-matrix-rooms-search.webp)

## Every day, done properly

The things you expect from a Matrix client, done properly.

- **End-to-end encryption.** Encrypted messaging on the Rust matrix-sdk. Device verification and key backup are built in.
- **Threads and forwarding.** Replies, Discord-style threads, and forwarding a message on to another room.
- **Media viewer.** View images and play audio and video in the app, without bouncing out to another window.
- **Voice transcription.** Long-press Space to dictate straight into the composer, via any OpenAI-compatible backend.
- **Offline spellcheck.** Multi-language checking that runs on your machine and picks up your system dictionaries.
- **Custom emoji.** Your own emoji, with CLDR keyword search, so typing `:whiskey` finds 🥃.
- **Metadata stripping.** EXIF, IPTC, and XMP data is stripped from images before upload, on by default.
- **Application profiles.** Keep separate accounts in separate profiles and switch between them cleanly.
- **Message effects.** Little touches like rain and thunder over a message when the moment calls for it.
- **Themes to spare.** 10+ built-in themes tuned for WCAG AA contrast, plus themes you write yourself.
- **30+ languages.** Komai probably speaks your language already.
- **Keyboard and Vim.** A keyboard-driven main workflow, with shortcuts in both plain and Vim style.

## Download

Free, open source, and always the current build. Pick your platform. Desktop only today: Linux, macOS, and Windows. No mobile build, and we’re not going to pretend the roadmap is the present.

### Linux

x86\_64 and arm64.

- **AppImage**, one portable file that runs just about anywhere
- **Flatpak**, sandboxed, straight from the release page
- **Arch**: `komai-bin` (prebuilt) or `komai` (from source) on the AUR

The AppImage needs FUSE 2. If it refuses to start, that’s usually the missing piece: `sudo apt install libfuse2` on Debian or Ubuntu, `fuse2` on Arch.

### Windows

x64, Windows 10 22H2+.

- **Portable ZIP**, no installer. Extract anywhere and run `komai.exe`

Not code-signed yet, so Windows throws a SmartScreen warning on first launch. Click **More info**, then **Run anyway**, and you’re in. No auto-update yet, so each new version is a fresh download.

### macOS

Apple Silicon, macOS 13.3+.

- **DMG** for Apple Silicon Macs. Drag `komai.app` into Applications.

Not signed or notarized yet, so Gatekeeper gets nervous on first launch. On macOS 13 and 14, right-click the app and hit **Open**. On 15 and up, open it once, then approve it under System Settings, Privacy & Security, **Open Anyway**. Apple Silicon only for now, and no auto-update yet either.

[Download Komai](https://github.com/etkecc/komai/releases/latest)

Want an older version, a checksum to verify against, or a URL to pin in your own scripts? It’s all on the [GitHub releases page](https://github.com/etkecc/komai/releases). The dedicated landing page lives at [komai.chat](https://komai.chat/).

## Support and links

- 💬 Matrix room: [#komai:etke.cc](https://matrix.to/#/%23komai:etke.cc)
- 🐙 Source: [github.com/etkecc/komai](https://github.com/etkecc/komai)
- 📖 Docs: [the user guide](https://github.com/etkecc/komai/blob/main/docs/README.md)

Komai is built by the etke.cc team, on the [matrix-rust-sdk](https://github.com/matrix-org/matrix-rust-sdk), and it began as a fork of [nheko](https://nheko.im/nheko-reborn/nheko) by the Nheko-Reborn team. Thanks, folks. The room search inside it runs on [matrixrooms.info](https://matrixrooms.info/), the Matrix room index we also maintain.

Like the client but would rather not babysit a homeserver? We run managed Matrix hosting, [order](https://etke.cc/order/) one and Komai will have a server to call home. Compare Komai against the other clients we recommend on the [clients page](https://etke.cc/help/clients/).


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* [llms.txt](https://etke.cc/llms.txt): full site index in markdown