JARVIGManual

ADR-0001 — One engine, multiple hosts

Status: Accepted Date: 2026-09-22

Context

The founding specification requires the editor to contain the real engine. A separate editor scene format would diverge from the shipped game and from the dedicated server.

Decision

JARVIG has one engine. The Hub, Editor, game client, dedicated server, and CLI are hosts. The editor viewport and Play-In-Editor run that engine. The server uses the same world and simulation architecture and omits editor and renderer systems. Game code does not call editor APIs.

Alternatives Considered

  • A standalone editor that exports a baked level the game loads. Rejected. It splits the world contract.
  • Two engines that share a file format. Rejected. Behavior would drift even if files matched.

Consequences

Hosts compose engine modules. Engine packages cannot import host packages. PIE copies or snapshots the authoring world instead of toggling a mode bit on it.

Supersedes

Nothing. This is the founding topology in designdoc.html sections 1 and 4.

Superseded By

Nothing.