Term	Definition
Wayland	The display server protocol used by modern Linux desktops, replacing X11
Compositor	The program that manages windows and display output (e.g., Hyprland, Niri)
Layer shell	A Wayland protocol (wlr-layer-shell) that allows surfaces to be placed in specific layers (Background, Bottom, Top, Overlay)
Layer surface	A Wayland surface managed by the layer shell protocol
Anchor	Edges of the screen that a layer surface attaches to (top, bottom, left, right)
Exclusive zone	Screen space reserved by a layer surface that other windows won’t overlap
Output	A display/monitor in Wayland terminology
SCTK	Smithay Client Toolkit — Rust library for Wayland client development
xdg_popup	Wayland protocol for creating popup surfaces attached to other surfaces

Term	Definition
iced	The Rust GUI framework used by ashell
Element	An iced widget tree node — the return type of view()
Task	A one-shot async effect that produces a message when complete
Subscription	A long-lived event stream that continuously produces messages
daemon	iced’s multi-window mode, where the application manages multiple surfaces
Theme	iced’s styling system with palette-based colors
Palette	A set of named colors (background, text, primary, secondary, success, danger)
Widget	A UI component (button, text, row, column, container, etc.)

Term	Definition
Module	A self-contained UI component displayed in the bar (e.g., Clock, Workspaces, Settings)
Service	A backend integration that communicates with system APIs (e.g., audio, bluetooth, compositor)
Islands	A bar style where each module group has its own rounded background container
Solid	A bar style with a continuous flat background
Gradient	A bar style where the background fades from solid to transparent
Menu	A popup panel that appears when clicking certain modules
Centerbox	Custom widget providing a three-column layout with true centering
ButtonUIRef	Position and size information of a button, used for menu placement
Hot-reload	Automatic application of config changes without restarting
Tempo	The advanced clock module (replacement for the deprecated Clock module)
Custom module	A user-defined module that executes shell commands

Term	Definition
MVU	Model-View-Update — the Elm Architecture pattern used by iced
Message	An event type that triggers state changes (the “Update” in MVU)
Action	A module-level return type that communicates side effects to the App
ServiceEvent	The standard event enum for services (Init, Update, Error)
ReadOnlyService	A service that only produces events (no commands)
Service (trait)	A service that produces events and accepts commands
Broadcast	The pattern used by the compositor service to share events across multiple subscribers

Term	Definition
D-Bus	The standard Linux IPC mechanism for communicating with system services
zbus	The Rust crate used for D-Bus communication
BlueZ	The Linux Bluetooth stack
NetworkManager	Standard Linux network management daemon
IWD	iNet Wireless Daemon — Intel’s lightweight wireless daemon
UPower	Power management daemon (battery info, power profiles)
MPRIS	Media Player Remote Interfacing Specification — D-Bus interface for media player control
StatusNotifierItem	D-Bus protocol for system tray icons
logind	systemd’s login manager (handles sleep/wake, power actions)
PulseAudio	Linux audio server (also provided as a compatibility layer by PipeWire)
PipeWire	Modern Linux multimedia framework (replaces PulseAudio and JACK)
Nerd Font	A font family patched with programming icons and symbols
cargo-dist	Rust tool for creating distributable binaries and installers
nfpm	Tool for creating .deb and .rpm packages