# Recipe: local command log

A hemx app may feel local-first without making hemx core a client database or
sync framework. The local artifact is an app-owned command/event log plus a
projection; hemx effects are rendered output, not stored truth. req: local/001
req: local/002

## Decision: no `hemx-local` crate yet

`hemx local` remains an app/recipe pattern for now, not a reusable hemx layer.
The host capability path proves that thin typed contracts work when the shared
semantics are obvious: manifest, call, event, and host-check failure. The local
exemplar proves a safer boundary for offline work: command, domain event,
projection, then generated UI effects. It does not yet prove common storage,
reconciliation, export, deletion, or conflict semantics across apps, so a crate
would freeze product policy too early. req: local/002 req: local/003 req:
local/004

A future reusable layer must first prove at least two independent apps share the
same command-log contract without sharing domain policy, storage provider, sync
provider, or conflict rules. Until then, recipes and app-owned integrations are
more honest and easier to delete. req: local/002 req: local/003

## Shape

```text
user intent
→ LocalCommand
→ domain validation
→ LocalEvent
→ Projection
→ generated UI effects
```

The log may live in memory, IndexedDB, SQLite, a native host store, or another
app-chosen persistence layer. That storage choice is not hemx core. req: local/002

## Replay and sync

Replaying local work to a server, remote AI/STT gateway, backup target, or peer
sync engine is explicit product policy. The app decides what can be queued,
exported, deleted, reconciled, retried, rejected, or redacted. A local projection
can render immediate feedback while those decisions remain pending. req: local/003

## Boundary

Do not persist DOM patches as truth. Do not persist generated UI effect payloads
as the local application log. Those are render instructions produced after
app/domain code accepts commands and projects events. req: local/001 req:
local/004

Use `hemx-host` only when the local log needs device or shell capabilities such
as secure storage, files, haptics, microphone, or notifications. The host still
returns facts; app code still owns the command/event/projection policy. req:
host/002 req: local/003