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The Desktop

LoricaOS ships a complete graphical desktop on the desktop ISO. It is built from four cooperating pieces — the Bastion greeter, the Lumen compositor, the Glyph toolkit, and the Citadel dock — plus a set of small applications, each one its own program shipped as a signed herald package.

Nothing here is a monolith. Lumen owns the screen and draws the desktop; every application is a separate process that connects to the compositor over an AF_UNIX socket to ask for a window. There is no in-process plugin model and no shared display authority — the same boundary the rest of LoricaOS is built on runs straight through the GUI.

Bastion — the login greeter

The first graphical thing you see on a desktop boot is Bastion, the display manager and greeter. It draws the LoricaOS logo and a username/password prompt directly to the framebuffer — before any compositor exists yet — and authenticates you against the system credential store (/etc/passwd + /etc/shadow).

On a successful login, Bastion elevates the session (binding your verified uid/gid so the session can only ever assume that identity) and launches the Lumen compositor as you. On a text-console boot it is never started at all.

Logging in on the live ISO

The live image ships a single account. At the Bastion prompt, log in with:

  • Username: live
  • Password: live

Privileged actions (the installer, Settings' admin panes) prompt for the live system's admin password: administrator. (On an installed system this is the admin password you chose at install time — change it any time with adminpw.)

The live session also auto-starts the graphical installer's dock icon, so you can install to disk from inside the desktop.

Lumen — the compositor and display server

Lumen is the heart of the desktop: the compositing display server. It maps the framebuffer, draws the desktop background, and is the single process every graphical application talks to in order to get a window. The visible furniture Lumen draws itself is:

  • The top bar — spanning the top of the screen, with the LoricaOS menu at the top-left (power, restart, "About", and quick actions), and a clock and volume control at the right.
  • Frosted-glass windows — application windows are composited with soft shadows, rounded corners, and a translucent frosted-glass chrome that blurs the desktop behind them. An elevated/admin window gets an unmistakable red titlebar tint so you always know when you're running something privileged.
  • The Citadel dock — the launcher bar pinned to the bottom-centre (see below).
  • A dropdown terminal — a quake-style terminal that slides down over whatever you're doing. Toggle it any time with Ctrl+Alt+T.

Apps are external clients, not plugins

Each GUI application is an independent program that connects to Lumen's socket at /run/lumen.sock. The handshake is simple: the app asks for a window, Lumen hands back a shared-memory buffer (memfd) over the socket, the app draws its pixels into that buffer and tells Lumen which regions changed, and Lumen composites them onto the screen. Input — keyboard, mouse, focus, drag-and-drop — flows back to the focused app over the same socket.

This means a misbehaving app cannot scribble on the framebuffer, read another app's input, or take down the desktop. It only ever sees its own window. In capability terms, a pure GUI client is granted service and nothing more; Lumen itself holds only FB (framebuffer), THREAD_CREATE, PROC_READ, and POWER.

Glyph — the toolkit underneath

Every graphical component links Glyph, the LoricaOS GUI toolkit. Glyph provides the software drawing primitives, the TTF text rendering (Inter for UI, JetBrains Mono for the terminal), the runtime theme system, procedural icons, the terminal-emulator core, and the client side of Lumen's window protocol. It is a build-time library baked into each app — there is no shared runtime to install. It's also why the desktop has a single consistent look and a live theme: light/dark mode and the accent colour are read from /etc/aegis/theme.conf and ~/.config/aegis/theme.conf and applied without a restart.

Citadel — the dock

The Citadel dock is the persistent launcher bar at the bottom-centre of the screen. Like every other app it's an external client of the compositor: it draws a row of frosted-glass app icons into a panel Lumen gives it, and when you click an icon it asks Lumen to launch that app (the compositor resolves the name against the /apps bundle registry and spawns it). The dock holds no capabilities of its own — it launches apps by asking the compositor, not by spawning them itself. It also can't be closed from the UI.

For the full list of installed apps, click the Applications icon to open the full-screen, Launchpad-style application grid.

Window controls

Every application window has a titlebar along its top. At the top-left sit the traffic-light controls:

  • Close — closes the window.
  • Minimize — hides the window.
  • Maximize — fills the screen.

Drag the titlebar to move a window around the desktop. Click anywhere in a window to focus and raise it to the top of the stack.

The apps

The desktop image ships the applications below. Each is a standalone herald package installed as an /apps bundle — launch them from the dock or the Applications grid.

App What it does
Terminal A full terminal emulator window (/bin/terminal) — separate from the built-in Ctrl+Alt+T dropdown.
Files Graphical file manager for browsing the filesystem, with drag-and-drop.
Text Editor A simple plain-text editor for viewing and editing files.
Settings System settings — theme (light/dark + accent), clock format, wallpaper, night light, pointer, and more.
Calculator A basic calculator.
Run A "Run…" launcher: type a command or app name to start it.
Tunes A minimal music player; streams WAV/MP3 to the audio device.
Calendar A month-view calendar.
Image Viewer Opens a single image with fit / zoom / pan, and can drag the file back out.
System Monitor A live task and resource monitor — memory bar, uptime, process count, and a sortable process list.
Network Manager Shows live eth0 configuration — link state, IPv4 address, subnet, gateway, DNS, and MAC — refreshed automatically.

Adding more apps

These are just the apps that ship on the desktop image — the desktop is not a fixed set. Every app is a signed .hpkg package, so you can install more with the herald package manager (herald install <name>). See Packages for how packaging and installation work.