Module layout 

Where a city keeps each kind of file on disk: one derivation from the city root and an address (crates/kernel/spec/Layout.lean §8-56).

Every directory name and file name the city writes is declared here once, and every path it writes them to is spelled here once, so a rename reaches every caller and none is left reading an empty directory.

Nothing here touches a disk. A CityLayout is a value: it answers where a file would be, and the caller that owns the I/O decides whether to create it, read it, or refuse. That keeps the layout inside kernel, where the address grammar it rests on already is.

One rule governs the placement itself: what governs a scope lives in that scope’s reserved subtree, and no write domain reaches it (Address::is_reserved). The rules of a building, its configuration layer and its filters are therefore under RESERVED_PREFIX, while the documents residents write — the job, the handoff, the urbanite page, the archive — sit in the open where residents can edit them.

Structs

CityLayout

The disk layout of one city, derived from its root.

Constants

ARCHIVE_DIR

Where a building files work it has finished with, by kind and day.

BUILDING_SHELF

A building’s own shelf of skills, under that building’s reserved subtree: what this building knows and no other building is given.

CAS_DIR

The content-addressed object store, under the city’s reserved subtree.

CONFIG_FILE

What one configuration layer declares. The same file name at every layer, because the layer is the scope it sits in rather than a name.

DEVICES_FILE

The devices paired to reach the city from outside the machine.

FILTERS_FILE

What a scope keeps out of the transcript it sends to a model.

GUIDE_FILE

How far the person has got through the first-run guide, under the city’s reserved subtree.

HANDOFF_FILE

What the next agent needs before it starts, per room.

JOB_FILE

The task of one session, in the room it is run from.

LEDGER_DIR

The append-only history of a city, under the city’s reserved subtree.

LIBRARY_DIR

The city’s shelves of skills, under the city’s reserved subtree.

MONITOR_FILE

The beat the performance monitor samples at, under the city’s reserved subtree (crates/sprawling/spec/Monitor.lean D48).

PLAYBACK_DIR

Where residents’ playback exports land, under the city’s reserved subtree, one directory per building.

REMOTE_DIR

What the remote gate keeps on disk, under the city’s reserved subtree.

RUN_ID_PATTERN

A run id as a git ignore pattern: one ? for each character of the hyphenated form a crate::RunId displays, so a building can keep every run’s transcript out of its history by name.

SKILL_FILE

The one document of a skill filed as a directory: a package on a section shelf, and every skill on a shelf the city mounts from elsewhere. It is the layout pi, claude and agents all use; the catalog lists this file’s first line, and read opens the files beside it by <name>/<path>.

SNAPSHOT_DIR

What the views held after one ledger line, under the city’s reserved subtree; a projection a start may discard.

TRANSCRIPT_EXT

The extension of what one run saw, written in its room as <run>.jsonl.

URBANITE_FILE

Who a standing resident is, in that resident’s own directory.

Functions

document_staging_name

What the staging file of a document named name is called: the name hidden by a dot and suffixed .staging, in the document’s own directory (crates/kernel/spec/Layout.lean §8-56).

is_document_staging_name

Whether name is spelled the way document_staging_name spells the staging file of some document.