{
  "title": "login flow",
  "direction": "tb",
  "nodes": [
    { "id": "app", "label": "Mobile app", "kind": "client" },
    { "id": "gateway", "label": "API gateway", "kind": "service" },
    { "id": "auth", "label": "Auth service", "kind": "service" },
    { "id": "sessions", "label": "Session cache", "kind": "cache" },
    { "id": "users", "label": "Users DB", "kind": "datastore" },
    { "id": "idp", "label": "Google OAuth", "kind": "external" },
    { "id": "audit", "label": "audit.events", "kind": "queue" }
  ],
  "edges": [
    { "from": "app", "to": "gateway", "label": "POST /login" },
    { "from": "gateway", "to": "auth" },
    { "from": "auth", "to": "idp", "label": "verify token" },
    { "from": "auth", "to": "users" },
    { "from": "auth", "to": "sessions", "arrows": "both" },
    { "from": "auth", "to": "audit", "style": "async" }
  ]
}