Lulo Documentation

Design and technical reference for Lulo — a terminal Linux management and observability tool. Last updated 2026-06-29.

Lulo is built on a three-process architecture: a Notcurses TUI frontend (lulo), an unprivileged user/session daemon (lulod), and a privileged system daemon (lulod-system). The frontend never writes a system file — all privilege is concentrated behind two Unix-socket protocols and reached through an authenticated RW lease. These pages document each component from its real implementation: the scheduler engine, the IPC and auth model, the focus providers, and every TUI page.

Architecture & Design

• Architecture Overview CORE
  The three processes, the privilege boundary, source layout, and design rules.
• Process Model & IPC CORE
  The two sockets, the wire protocol, the embedded polkit auth agent, the RW lease, edit sessions, and proc tracing.
• Scheduler CORE
  Sparse-overlay profiles, fnmatch matchers, the exclude/focus/rule/background resolution, and continuous syscall-level enforcement.
• Focus Providers CORE
  KDE and GNOME focused-window detection over one session-bus contract, with opposite data directions.

TUI Pages

• CPU & Process View PAGE
  The decoupled CPU/proc sampling pipeline, per-core heatmap, arena-built process tree, and tracing.
• Disk View PAGE
  A daemon-free, synchronous multi-panel dashboard over /proc, /sys/block, and the mount tables.
• Cgroups View PAGE
  A live /sys/fs/cgroup browser bridged to the systemd unit definitions that shape each limit.
• Systemd View PAGE
  A merged system + user inventory over sd-bus, with true reverse-dependency closures.
• Tune View PAGE
  A live tunables explorer with staged edits, portable .ltune bundles, and a privileged apply path.
• Udev View PAGE
  Rules, hwdb, and live device records read straight from /run/udev/data — no libudev.

Build & Operations

• Install & Packaging OPS
  Build targets, the /usr footprint, the two systemd units, the GNOME extension step, and packaging.

Lulo by Jordan Johnston — github.com/nine7nine/lulo
Terminal Linux management & observability | 2026-06-29