Registered managed global/runtime properties for modes, viewport values, and app/system flags.
Owns
- managed property registration, observable value, validation, and snapshot
- primary tool, zoom, interaction-mode, and app-defined system-level state
- persisted-versus-runtime-only registration option
- instance-bound validate-then-apply load artifacts
Does not own
Entity graphs, property components, UI binding, default event subscriptions, render output, or app-domain command policy.
Compose when
Compose it for small global values that are not element/property graph data. Core already exposes managed-property facades. Do not use it as an arbitrary document store or duplicate per-entity Props state.
Public entrypoints and prerequisites
Use @asyra/system-context or Core's defineSystemProperty(...), setSystemProperty(...), getSystemContextSnapshot(), query, load/save, and unregister facades. Define initial value, optional validator, and whether the property is runtime-only before use.
Lifecycle, inputs, outputs, and failure
Registration creates one consistent observable value source. Runtime set validates before update. Load validation normalizes unregistered/invalid values according to the owner contract and issues one instance-bound artifact; apply accepts that artifact once without rerunning validators. Foreign, stale, reused, or invalid artifacts fail before mutation.
SystemContext.resetRuntime() removes managed registrations and old validation artifacts and completes their observables after work is quiescent. It attempts every completion and reports cleanup failure; independent context state is unchanged. Apps use Core lifecycle orchestration, not private state access.
Relationships
Core coordinates public registration, read/write, frame request, and load/save ordering. Reactive adapters map events to managed values. UI Context/Render can derive presentation. Persistence includes only registrations marked non-runtime.
Maintained use path
Study information models for a custom managed record. The app retrieval/action guide uses a read-only snapshot and registered Feature API for mutation.
Replacement and disabled behavior
Apps may define/unregister their own managed properties while composition is open. Runtime-only values are intentionally omitted from persistence. When a property is unregistered, consumers must handle absence; no stale snapshot or UI default becomes its owner.
Support, migration, and deprecation
Current validation/load uses owner-issued artifacts and safe initialized defaults. Migration of app values remains app-owned before load. Preserve registration identity and validator semantics; do not fabricate artifacts or mutate observable internals.
Canonical sources and release inventory
The root entrypoint, version, and dependencies are generated from the manifest and release-checked.