# S012 — login UX + deploy shape

Design pivot (mvp.dj decision 8): email/SMS sign-up splits into a
**separate app**; linji.at hosts on Fly.io and accepts BYO atproto
handles from any PDS.

## What landed

- **BYO-handle login**: `beginLogin` resolves an external handle the
  standard way — `.well-known/atproto-did` → DID document →
  `#atproto_pds` service — and runs OAuth against that server. Falls
  back to the configured PDS for handles that don't resolve (the dev
  rig's `.test` accounts).
- `linji serve` flags: `--handle-domain` (bare login names suffix it;
  default `linji.at`), `--invite-code` / `LINJI_INVITE` (403 at
  `/api/login` without it), `/api/config` (domain + inviteRequired).
- **PWA**: full-handle login with the community suffix as a hint, invite
  field shown only when required (remembered in localStorage), spinners
  on composer + new-thread, mobile layout (16px inputs against iOS zoom,
  horizontal space chips, sticky composer, safe-area padding).
- **Service worker rewritten** after a real stale-shell incident
  (cache-first shell stranded the tab on dead asset hashes): now
  network-first for navigations, cache-first only for hashed `/assets`,
  `/api` always network, `skipWaiting` + `clients.claim`.
- **Deploy**: `app0/fly.toml` + multi-stage Dockerfile (zig → bun →
  slim runtime; zds is a separate deploy via `LINJI_PDS` secret).
  `app0/dinit/` dev services with relative paths:
  `dinit -d app0/dinit dev` boots zds + seed + serve + vite.

## dinit facts (learned via dinit-check + live boot)

- `env-file` paths resolve relative to the **service directory**.
- Relative command paths work; `dinit-check` warns but they run.
- Logfile directories must exist before the service starts — use flat
  `/tmp` filenames when a seed script creates the state dir later.

## Verification

scenario-serve extended (`/api/config`, invite denials, bare-name
login) — 32 checkpoints, PASS; unit + scenario-space green. dinit dev
stack booted live: fresh `/tmp/linji-dev` seeded, bare-name `alice`
login worked, vite proxy 200, clean shutdown. Spinner confirmed under
throttled network; mobile layout screenshot-checked at 390×844.