# user-engine application binding

| Field | Value |
|-------|--------|
| application id | `coulomb-social` (`USER_ENGINE_APPLICATION_ID`) |
| display name | coulomb.social |
| tenant (v1) | `tenant:coulomb` (KeyCape default; Binky friendly slug later) |
| identity link | `(issuer, sub)` via user-engine `GET /api/v1/me` auto-provision |
| local row | `members.Member` (no passwords) |
| live base URL | `https://users.92-205-62-239.nip.io` (cluster ingress) |

## Runtime

| Mode | When | Behavior |
|------|------|----------|
| **stub** | `USER_ENGINE_BASE_URL` or `USER_ENGINE_PROXY_SECRET` empty | Deterministic `user_id` from sha256(iss\|sub) |
| **http** | both set | Trusted-proxy `GET /api/v1/me` with IAM-shaped claims envelope |

### Trusted proxy envelope

user-engine accepts claims only when:

```http
X-User-Engine-Proxy-Secret: <secret from user-engine-runtime>
X-Verified-Oidc-Claims: {"iss","sub","tenant","principal_type","aud",...}
```

`aud` must include the portal audience `user-engine-portal` (deployed expectation)
plus `coulomb-social`. Trust is the proxy secret; claims were verified by
KeyCape OIDC at the app edge.

### Operator: enable HTTP mode locally

```bash
# secret never printed to shell history if you use process substitution carefully
export USER_ENGINE_BASE_URL=https://users.92-205-62-239.nip.io
export USER_ENGINE_PROXY_SECRET="$(kubectl -n user-engine get secret user-engine-runtime \
  -o jsonpath='{.data.proxy-secret}' | base64 -d)"
export USER_ENGINE_EXPECTED_AUDIENCE=user-engine-portal
# then OIDC or dev-login
```

OpenBao lane for the proxy secret (future): document under railiance-platform
workload KV; until then kubectl-sourced secret is operator-only on the workstation.

## Profile attributes (shell only)

- display name (OIDC `name` / user-engine user.display_name)
- email (optional)

Bubble content fields are **not** part of this binding.

## Live probe (2026-08-09)

`GET /api/v1/me` with probe claims returned `user_id` `usr_…` and
`actor.tenant=tenant:coulomb` (HTTP 200).