baguette

A minimal Wayland HUD / status bar written in C17.

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baguette is a lightweight overlay bar for wlroots-based Wayland compositors. It draws a left / center / right status bar using Cairo on a layer-shell surface, and stays deliberately dumb: it does not collect any data itself.

Instead, baguette reads frames on stdin — one line per frame — and renders them. You bring the content by piping any program into it. A ready-made content generator, za'atar, produces CPU/GPU temps, memory, audio, uptime, date and workspace info out of the box (see Example).

Contents

• Download
• Build from source
• Usage
  • Layout styles
  • Input format
  • Styling
• Example: za'atar

Download

Prebuilt baguette binaries are published on the Releases page.

# Grab the latest release binary
curl -L -o baguette https://github.com/IdanKoblik/baguette/releases/latest/download/baguette
chmod +x baguette
./baguette

The binary is dynamically linked against wayland-client, cairo, libconfig and libm, so make sure those runtime libraries are installed. If you'd rather build it yourself, see below.

Arch Linux (PKGBUILD)

Arch users can build and install a proper package with the bundled PKGBUILD, which derives the version from git, runs the test suite and pulls in the runtime dependencies automatically:

git clone https://github.com/IdanKoblik/baguette.git
cd baguette
makepkg -si

makepkg -si builds the package and installs it (and its dependencies) with pacman.

Build from source

baguette is plain C17 with a Makefile — no build system to learn.

Dependencies:

• A C compiler (cc / gcc / clang)
• make
• pkg-config
• wayland-client and cairo development packages
• libconfig development package
• wayland-scanner (generates the protocol code)

On Arch:

sudo pacman -S base-devel wayland cairo libconfig

Build:

make          # build the ./baguette binary
make run      # build and run
make clean    # remove build artifacts and generated protocol code

Optional developer targets:

make test      # build and run the unit test suite
make coverage  # run tests under coverage, emit an HTML report (needs lcov)
make compdb    # generate compile_commands.json for clangd (needs bear)
make logs      # export baguette's journald logs to baguette.log

See CONTRIBUTING.md for code conventions and how to add tests.

Usage

Run baguette and feed it frames on stdin. The simplest possible test:

# A static one-frame example: left / center / right
printf 'hello\tcenter\tworld\n' | ./baguette

baguette keeps the bar up for as long as stdin is open, redrawing only when the incoming frame actually changes. Send SIGINT/SIGTERM (or close the pipe) to exit.

Layout styles

Flag	Behaviour
--separated	Separate rounded pills per section (default)
--full	One full-width background bar

./baguette --full

Input format

Each line of stdin is one frame. A frame is split into up to three sections by tab characters:

LEFT  \t  CENTER  \t  RIGHT

Each section is plain text with optional inline colour tags:

Tag	Meaning
%{#rrggbb}	colour the text that follows
%{-}	reset to the default colour
%%	a literal %

A colour tag applies from where it appears until the next tag or the end of the section, so one section can carry several differently-coloured runs. Anything that isn't a recognised tag is kept literally — input is never silently dropped.

# Red "CPU 72°C" on the right, default-coloured workspace on the left
printf ' 1 2 3\t%%{#ff5555}CPU 72°C%%{-}\n' | ./baguette

Styling

Global look (font, colours, sizes) is read from a libconfig file at:

~/.config/baguette/style.cfg

You don't have to create it yourself: the first time baguette starts and that file is missing, it writes a default style.cfg to that path. Run baguette once, then open the file and tweak it to taste. (You can also copy assets/style.cfg there as a starting point.)

Available keys:

font = "JetbrainsMono Nerd Font";   # font family (default: "monospace")
font_size = 14.0;                   # point size (default: 14.0)

height = 32.0;                      # bar height in px (default: 32.0)
background = "#101010";             # "#RRGGBB" hex colour (default: "#000000")

hud_padding = 8.0;                  # inner padding around content (default: 8.0)
radius = 12.0;                      # corner radius of the pills (default: 5.0)
vmargin = 4.0;                      # vertical margin from the screen edge (default: 4.0)
pad_x = 6.0;                        # horizontal padding per section (default: 8.0)

Numbers may be written as integers or floats interchangeably (radius = 12; and radius = 12.0; both work). After editing, restart baguette to pick up the changes.

Example: za'atar

za'atar is a small Python content generator built specifically for baguette. It emits exactly the left \t center \t right wire format on stdout, so you just pipe it in:

# Clone the generator
git clone https://github.com/IdanKoblik/zaatar.git
cd zaatar

# Pipe its output straight into baguette
python3 main.py | baguette --full

za'atar fills the bar with:

• left — current workspaces
• center — date / time
• right — CPU & GPU temps, memory, PulseAudio volume, uptime, Tailscale status

To launch it automatically, add the pipeline to your compositor's startup (e.g. in your Hyprland/Sway config):

exec python3 /path/to/zaatar/main.py | /path/to/baguette --full

Anything that can print left \t center \t right lines works just as well — za'atar is just a convenient default.