> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crust.moumen.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Files on disk

> What crust writes, what to commit, and the two escape hatches.

```text theme={null}
.perf/
  schema.json              schema + tool version
  budgets.json             your budgets (you write this)
  aliases.json             route renames (optional)
  overrides.json           unresolvable imports (optional)
  builds/ab/ab3f91c2.json  one file per snapshot
  modules/9f/9f2c81.json   content-addressed module tables
  runs/01J8X…/             synthetic run samples
  index.db                 derived cache - gitignored, rebuildable
```

## Commit `builds/` and `modules/`

One file per snapshot, never a shared append-only log. A `history.jsonl` would conflict every single
time two branches both record a build - exactly when history is most worth having.

Module tables are content-addressed separately because module sizes repeat almost identically
between builds; inlining them would make each snapshot 50–200 kB of near-duplicate data.

Add `index.db` to `.gitignore`. It is derived and rebuilt by scan, and publishing it just creates
conflicts between machines that built it at different times.

## aliases.json

Trends are keyed on the page file path, which survives URL refactors but not file moves. An alias
stitches the history back together:

```json .perf/aliases.json theme={null}
{
  "app/old/page.tsx": "app/new/page.tsx"
}
```

## overrides.json

Manual answers for specifiers no resolver can settle - computed dynamic imports, exotic
plugin-resolved aliases. Maps a specifier to a workspace-relative file:

```json .perf/overrides.json theme={null}
{
  "@weird/alias": "packages/ui/src/index.ts"
}
```

<Tip>
  Do not chase 100% resolution in code when a ten-line JSON file covers the tail. crust reports what
  it could not resolve so you know exactly what to put here.
</Tip>

## schema.json

Records the snapshot schema version. It is bumped on any change to the stored shapes - a snapshot
outlives the tool version that wrote it, and silently reinterpreting old records under new semantics
is how a history feature starts lying about the past. `crust diff` refuses to compare across schema
versions.