Design & ideas

0xide is a dynamic tiling window manager for Wayland, written in Rust on wlroots. This chapter documents its design decisions — how the layout, configuration, and workspace model work and why — and the ideas planned next. It is updated as decisions are made.

Layout

There is one tiling layout — the spiral/dwindle described in Stage 5 — and it is recomputed from the window list’s order on every change. There is no persisted layout tree, no per-window split ratios, no manual layout mode.

The tradeoff: layout is a pure function of a Vec — reproducible, unit- testable against exact computed rectangles, with no layout state to corrupt or desynchronize. The cost is that some layout-shape questions have no clean answer; the corner-touch ambiguity in directional navigation is a direct consequence, and is documented with a test that pins the behavior. If per-window split control becomes a requirement, the structural fix is an explicit split-tree — listed under planned ideas below.

Configuration

Three rules, applied throughout src/config.rs:

1. Nothing is fatal. A line that doesn’t parse warns on stderr and is skipped. A missing config file means defaults. A config with zero bind lines still has every default binding. 0xide always starts.
2. User config merges, never replaces. A bind line overrides exactly that key combination; every unmentioned default stays active. A two-line config is a two-line diff, not a fork of the whole keymap.
3. Explicit over implicit. Monitor placement is literal pixel coordinates per named connector (monitor = eDP-1, 0x0) — no relative keywords, no DPI auto-scale heuristics. The config states what happens; nothing else does.

Workspaces and outputs

Nine workspaces, with one invariant: a workspace is never visible on two outputs at once. Switching to a workspace already shown on another monitor swaps the two monitors’ workspaces instead of duplicating it. New windows open on the monitor the cursor is on (focus-follows-monitor). The model stays predictable regardless of how many outputs are attached.

Decorations

0xide always claims server-side decoration and draws nothing in its place: every window is a bare, borderless rectangle. In a tiler the layout itself conveys what title bars and borders would — window position and focus are already visible from the arrangement.

Planned ideas

Under consideration, not committed:

• An explicit split-tree layout — per-window split ratios, interactive resize, and fully reversible directional navigation; the structural answer to the corner-touch limitation above.
• Floating exceptions — per-window rules for clients that shouldn’t tile (pickers, dialogs).
• Runtime control — a socket/IPC for querying and scripting the compositor without keybindings.

When one of these lands, it moves out of this list and into a stage chapter.