---
term: runtime
category: service
status: canonical
authority: world.elonn.local
---

Runtime

A complete executable presentation environment. Runtimes consume translated
World contracts. They are responsible for rendering, input handling, lifecycle,
performance, accessibility implementation, and platform adaptation.

Runtime instances:
- web runtime — the browser-based Elonn experience
- android runtime — the Android-based Elonn experience
- desktop runtime — the desktop-based Elonn experience
- xr runtime — the extended reality Elonn experience

"Runtime" has two additional distinct uses within the existing system and must be qualified when context is ambiguous:

World runtime (world.elonn.local)
A platform adapter that renders a translated World runtime contract. Existing
Web, Android, iPad, XR, desktop, and future device runtimes consume translated
primitives according to their capabilities.

Presence runtime (social.elonn.local)
The runtime field on a presence record identifying which client the member is currently using (e.g. web.elonn, mobile.elonn). This is a string identifier, not the execution environment itself.

Allowed:
- web runtime
- android runtime
- desktop runtime
- xr runtime
- world runtime
- browser runtime
- runtime contract (the payload from World that bootstraps every runtime)
- runtime authority (the world service's designation as the session authority)
- presence runtime (the client identifier in a presence record)

Forbidden:
- runtime alone when the meaning is ambiguous between world runtime and presence runtime
- backend (describes infrastructure; not a product term)
- server-side runtime (too technical; not a product term)
- client (too generic; use the specific runtime name)

Notes:
- The world service declares itself runtime_authority: true in its service response. This means it is the canonical source of the World model and translated runtime contracts.
- A surface may specify content_source.kind = runtime_panel and a content_source.url — the URL the runtime fetches to load that surface's panel content. This is a "runtime" URL in the sense that it is fetched at execution time, not build time.
- Runtimes execute translated contracts. They do not own translator logic or
consume service payloads directly.

Related:
- contract
- world
- translator
- web
- panel
- presence (presence runtime field)