Getting Started

# Getting Started

## Install

The [Download page](/download/) has packages and archives for Linux,
macOS, and Windows.

Or build from source with a recent stable [Rust](https://rustup.rs):

```sh
git clone https://github.com/crmne/fastsapp
cd fastsapp
cargo install --path .
```

On Linux the build needs the development packages any egui application
does, plus ALSA and cmake (libopus and the H.264 decoder compile from
source). On Arch:

```sh
sudo pacman -S --needed alsa-lib libxkbcommon wayland cmake
```

On Debian or Ubuntu:

```sh
sudo apt install build-essential cmake libasound2-dev libxkbcommon-dev libwayland-dev libgl1-mesa-dev
```

A desktop entry ships in `packaging/applications/fastsapp.desktop`.

## Link with your phone

FastsApp is a companion device, like WhatsApp Web. Start it and either:

- scan the QR code with your phone (WhatsApp, **Settings**, **Linked
  devices**, **Link a device**), or
- click **Link with phone number** and type the eight-character code into
  the phone instead, when the camera is not handy.

The link survives restarts; your phone does not need to stay on the same
network, or online, for reading what has already arrived.

## The history arrives twice

Right after linking, the phone sends the recent history: the chat list
fills within seconds, and messages keep streaming in for a few minutes.
From then on, FastsApp keeps everything it sees in its own archive, so its
history grows past what WhatsApp replays. Scrolling to the top of a chat
asks your phone for what came before; the phone must be online to answer.

## A safe place to try things

Your own chat (the one WhatsApp calls **Message yourself**) behaves like
any other and is the place to try sending, reactions, edits, voice
messages, and attachments without an audience.

Install

The Download page has packages and archives for Linux, macOS, and Windows.

Or build from source with a recent stable Rust:

git clone https://github.com/crmne/fastsapp
cd fastsapp
cargo install --path .

On Linux the build needs the development packages any egui application does, plus ALSA and cmake (libopus and the H.264 decoder compile from source). On Arch:

sudo pacman -S --needed alsa-lib libxkbcommon wayland cmake

On Debian or Ubuntu:

sudo apt install build-essential cmake libasound2-dev libxkbcommon-dev libwayland-dev libgl1-mesa-dev

A desktop entry ships in packaging/applications/fastsapp.desktop.

Link with your phone

FastsApp is a companion device, like WhatsApp Web. Start it and either:

scan the QR code with your phone (WhatsApp, Settings, Linked devices, Link a device), or
click Link with phone number and type the eight-character code into the phone instead, when the camera is not handy.

The link survives restarts; your phone does not need to stay on the same network, or online, for reading what has already arrived.

The history arrives twice

Right after linking, the phone sends the recent history: the chat list fills within seconds, and messages keep streaming in for a few minutes. From then on, FastsApp keeps everything it sees in its own archive, so its history grows past what WhatsApp replays. Scrolling to the top of a chat asks your phone for what came before; the phone must be online to answer.

A safe place to try things

Your own chat (the one WhatsApp calls Message yourself) behaves like any other and is the place to try sending, reactions, edits, voice messages, and attachments without an audience.