Class Application

Backwards-compatible Google delegate — the test-auth seam and any Google-specific caller route through here. Forwards to the provider-parameterized path with provider: 'google'.

Find or create User + provider profile from an OAuth profile. The provider-parameterized spine: adding a provider is this argument, not a code fork. For new users, the roster starts empty (char-gen owns character creation). Returns the User's id.

Handle user connection. Loads the authenticated User, spins up an Interactive, and hands off to Login to run the entry procedure.

The read-only broadcast principal (isBroadcast) short-circuits before any of that: no User load, no Interactive, no Login, no Avatar — it's registered with the BroadcastFeed as a pure push target. With no Interactive in the connection registry it can never run a command (processUserMessage finds no holder) and is never routed game traffic.

Attach a provider profile to an existing User (authenticated link flow). Data-integrity logic lives here, not in a route handler:

• profile unowned → attach → linked
• profile already on user → no-op → already-linked
• profile owned elsewhere → refuse, no write → collision No merge: a collision is refused with a clear message.

Dispatch an inbound wire message. Resolves the Interactive, looks up the handler in inboundHandlers, and invokes it with a HandlerContext. Handler bodies live in backend/inbound/<substrate>.ts — adding a new message type means adding a handler file there and registering it in inbound/index.ts. Do not grow this method.

TEST-ONLY: give a user a ready-to-play default character so in-world E2E tests don't have to walk char-gen first. Mirrors the retired signup auto-mint (human, lobby, seed defaults), named from the test handle. Backs the test-auth seam's withCharacter option. Gated on AUTH_MODE === 'test'; idempotent (no-op if the user already owns a character).

Server→client push of a ClientStateMixin key. Used when the server mutates an overlay-shaped client-state key out-of-band (the style verb is the v1 caller); the client receives the authoritative value and re-renders without waiting on the reconnect snapshot. Sibling of sendMessageToInteractive — bypasses the Sensor pipeline (no frame, no frameId); it's wire-substrate plumbing, not narrative.

Envelope counterpart to sendMessageToInteractive. Stamps frameId per-Interactive from the same Interactive.nextFrameId counter used for prose frames — one ordering primitive across all server→client traffic.

Send a MessageFrame to a specific Interactive's client. Sole gateway for game objects to reach Backend — Application owns Backend communication. Stamps meta.frameId per-Interactive at send-time so multi-device Avatars receive monotonic streams from each Interactive's perspective.

Error / auth notifications (raw {type, payload} shapes) go directly through Backend.sendMessageToSocket and bypass this chokepoint — they're not Sensor-pipeline frames and have no frameId to stamp.

Detach a provider from an existing User and delete the orphaned profile (with its stored tokens). The collision-refuse rule guarantees single ownership, so deletion is safe.

• not linked → no-op → not-linked
• removal would orphan → refuse → only-provider
• otherwise clear + delete → unlinked

Wire the live broadcast-source push. When the operator changes the livestream embed sources (config livestream.broadcastSources), fan the new list to every connected player so the livestream-viewer embed updates without a reconnect. The welcome snapshot (ConnectionEstablishedPayload.broadcastSources) is the baseline.

Registered from AppBootstrap.run AFTER the EventRegistry is bootstrapped (the TwitchRelayReader.boot() precedent) — NOT in initialize(), which runs in the Server constructor before bootstrap.

Provider-agnostic default avatar name read at account creation. A throwaway (char-gen overwrites it), but a Twitch-origin user must not fall to 'Unnamed'. Google: givenName ?? displayName; Twitch: displayName ?? login.