Nomarchy/agent/MEMORY.md

Memory — durable lessons, learned the hard way

Curated, not append-only: one line per fact, newest at the top of its section; delete entries that stop being true. Details usually live in a docs/ROADMAP.md decision record — pointer given as (§ item). Add a fact here the moment a debugging session teaches you something a future iteration would otherwise rediscover.

Testing & VM recipes

• tuigreet dies silently under runNixOSTest (even bare, no theme flag: greetd sits as "(greetd)" with no child, nothing in the journal — its stderr goes to the VT) — nixpkgs' own greetd test uses agreety instead. Greeter rendering is interactive-ISO/hardware tier; don't burn another session on a checks.greeter VM test.
• In VM tests pgrep -f PATTERN can match the test backdoor's own bash -c wrapper (the pattern is in its cmdline) — use pgrep -x or a [t]uigreet-style bracket pattern.
• A checks.* fixture CANNOT be a writeText/toFile state file read at eval time ("path … is not valid" — flake check's eval store won't realise it): extract the logic into a pure importable file and unit-test THAT (monitor-rules.nix / checks.display-profiles is the pattern).
• CI (.gitea/workflows/check.yml) is eval-tier only: the act_runner is a docker container (no systemd, no /dev/kvm). Container gotchas are documented in the workflow header (single-user Nix + nixbld users, sandbox=false for Stylix IFD, Nix pinned 2.31.5 vs lazy-trees, no JS actions past node20) — learned over the legacy repo's 57 runs; read them before touching the workflow.
• The Gitea instance is 1.25.4 — on: schedule workflows are supported; bump.yml assumes the Actions token can push to main (standard Gitea behaviour, but unconfirmed until the first run lands).
• The git server is Gitea (gitea/act_runner via docker-compose), NOT Forgejo — workflows are read from .gitea/workflows/ (or .github/), never .forgejo/workflows/ (a whole push cycle was lost to that).
• Reusable headless VM harness: checks.* via runNixOSTest — existing examples to crib from: distro-id (boots + switch-to-configuration dry-activate), hardware-toggles (kernel cmdline/PAM assertions), battery-charge-limit (fake Mains adapter via test_power, real udev uevent, InvocationID change proves the restart).
• Themed-desktop screenshots work headlessly: software-GL Hyprland (LIBGL_ALWAYS_SOFTWARE on virtio-gpu) + machine.screenshot() QMP dump — prototyped 2026-06-19, kept as the fallback for theme previews (§ Visual theme picker).
• Hyprland/Ghostty need guest GL (virtio-vga-gl, gl=on) in interactive QEMU or the session won't start; black screen ≈ missing GL (docs/TESTING.md § gotchas).
• No KVM = slow, not broken; don't read slowness as failure.

Known-broken / watchlist

• btrfs-assistant "segfault" was unprivileged-only (re-diagnosed 2026-07-04): libbtrfsutil's unprivileged subvolume iteration crashes on btrfs-progs 6.17.1 (upstream-fixed after); as root it works, and the pkexec launcher runs it as root. The real distro bug was no polkit agent in the session (every pkexec failed silently) — hyprpolkitagent now ships (hyprland.nix exec-once). checks.snapshot-gui guards the root path. Lesson: before "app X is broken", check WHO it runs as — and whether polkit prompts can render at all (§ Snapshot browse/restore).
• NixOS release bump is a trap: the discarded attempt (branch deleted 2026-06-22) hit a Hyprland OOM blocker; a redo is a deliberate v2, never part of routine lock bumps.
• theme-state.json is git-tracked inside an 86 MB flake tree, so every state write re-copies the source before eval — the wallpapers-artifact split (BACKLOG LATER) is the decided fix (§ Faster switches).

Gotchas (cost a debugging session once)

• Waybar layer: top renders above even real-fullscreen windows — the bar draws over a fullscreen video. layer: bottom lets the fullscreen surface cover it while the exclusive zone still reserves the bar's space in normal tiling (trade-off: floating windows can now overlap the bar strip). Set in both waybar.nix and every whole-swap jsonc (item 30).
• Hyprland binds match the exact modmask: a shifted keysym (question) needs SHIFT in mods or the bind never fires — the keypress falls through to the focused window (§ item 26; caught on hardware, invisible to eval-tier tests).
• Never kill a Wayland session-lock client (hyprlock): its crash failsafe drops to a tty instead of unlocking (§ Hibernate double-unlock).
• rofi element-icon size is one value = a square cell; WxH silently collapses and non-square icons letterbox — pre-crop images square at build (§ Visual theme picker).
• WirePlumber 0.5 monitor rules can only early-match device.api; device.product.name etc. bind after the rule runs — surgical libcamera scoping is impossible (§ Webcam).
• hyprctl switchxkblayout is a global layout flip; per-device isolation needs device[<name>]:kb_layout keywords (§ Keyboard layouts).
• Waybar's clock captures the timezone at construction — a zone change needs SIGUSR2 (watcher in timezone.nix) (§ Automatic timezone).
• Waybar persistent_workspaces (underscore) is dead syntax silently ignored; the hyphen form is honoured and renders phantom workspaces (§ Waybar shows non-existent workspaces).
• GTK4/libadwaita/Qt6 read light/dark from the portal's org.freedesktop.appearance color-scheme (dconf), not Stylix polarity (§ GTK/Qt ignore the theme's mode).
• Update order matters downstream: sys-update (lock) before home-update, or desktop changes are silently skipped against the old lock (README § 3).
• grub loadfonts every .pf2 in a theme dir — reuse a bundled DejaVu rather than shipping fonts (§ Distro branding).
• The Claude Code harness drops machine-local files into the repo (.claude/skills/…) mid-session — never git add -A blindly; check git status --short for strangers first (they're gitignored now, but the next surprise won't be) (§ loop hygiene).