Native and artifact delivery (beta)

Both React/Svelte native targets and precompiled publication artifacts receive the same island input:

{
  "inputVersion": 1,
  "block": {
    "id": "authored-block",
    "type": "example:scene",
    "schemaVersion": 1,
    "contract": { "id": "<immutable contract ID>", "digest": "<digest>" }
  },
  "activation": "visible",
  "payload": null,
  "initialState": { "selected": 0 },
  "accessibility": { "label": "Example scene" }
}

payload is any JSON value, including arrays, strings, numbers, booleans and null; it MUST NOT be flattened or replaced with an empty object. Contract identity is present when source is locked. Content, fallback, accessibility, readable associations and optional initialState retain their authored structure. Services, executable loaders, DOM targets and lifecycle handles stay out of band. This is an atomic frozen-beta ABI update; there is no reader-side legacy interpretation branch. Incompatible artifact/input versions preserve fallback and receive explicit incompatibility markers.

Artifact versus native fidelity

Artifacts contain an HTML fragment, stylesheet and module identifiers, used island inputs, compatibility/static-fidelity report, diagnostics, output identity and optional reproducibility provenance. They are not framework templates or executable module mappings. Hosts separately approve implementation IDs and URLs; document-provided module-like strings do not execute themselves. publicationReaderManifest extracts only format, version, identity, compatibility and islands for attachment, avoiding duplication of SSR HTML, resources, diagnostics or source AST in browser data. The publication-runtime entry excludes schema validators, compiler, registry and formatter tooling.

Static lowering/fallback is reported and is not a promise of arbitrary framework visual equivalence. Used modules/styles are deduplicated. Payloads and declared datasets are not unsafely pruned merely because a renderer appears not to read them. No full source AST/schema/registry is delivered solely for rendering. Three.js, Mermaid and other computation engines remain host-side implementations.

Placement and CSS policy

Compiler-generated IDs, fragment links, label/form associations and ARIA token references are namespaced per placement. Hosts supply a unique instance ID matching [A-Za-z][A-Za-z0-9_-]{0,63}. Generated React/Svelte targets use framework-owned IDs when a host does not supply one. Repeated placements do not share interactive state. Compiler-generated CSS is rooted under Publisle classes; approved components/styles remain the host's responsibility. Arbitrary authored trusted HTML cannot be generically rewritten into safe scoped markup; artifact compilation rejects identity-bearing raw HTML by default. rawHtmlPlacement: preserve produces a warning and requires host restrictions.

Hosts remain responsible for sanitization, CSP, stylesheet/asset origins and internal component IDs. Raw HTML opt-in is not a sanitizer. Browser acceptance verifies native/artifact JSON input parity, repeated ID/reference behavior, independent state and the absence of preparation tooling from readers. It does not claim a universal CSS reset or numerical equivalence of user engines.

Lifecycle and activation

createIslandController is the framework-independent browser lifecycle. React and Svelte leaf adapters, and artifact attachPublication, call it. A small vanilla host can call it directly. There is no separate reader ABI version; inputVersion and the publication format remain 1. hydrate stays unsupported and is marked data-publisle-unsupported-mode rather than partially applied.

The first gesture only activates. It does not replay the browser event and it does not invoke a named semantic action. props stay the authored island input.

load receives an AbortSignal. destroy aborts that signal, ignores a late result, and unmounts at most once. A second activate while a mount is pending or complete does not mount again. A failed load keeps the activate control available for retry, leaves the fallback visible, marks data-publisle-status="failed", and moves focus back to the activate control. A successful load moves focus from that control to the mount root and marks data-publisle-status="ready". During the load the scope is aria-busy="true". That status is not an invented description of the output. Hosts announce meaningful output changes themselves.

Implementations load on activation. Repeated placements share a module load and keep independent mounts; rejected imports are cleared so another activation can retry. Optional suspend: true cancels pending loads or unmounts a visible island that leaves the viewport and mounts it again on return. Suspension is off unless the host opts in. When prefers-reduced-motion: reduce matches, idle activation runs immediately and publication CSS disables animation and transitions on interactive regions. Print CSS hides the activate control and the mount root and shows the authored fallback. A locked contract id and digest are copied onto data-publisle-contract on native/artifact boundaries and the explanatory region, including when a renderer is missing. That attribute records provenance; it does not make a snapshot the editable source.

Pointer-only host canvases still have to expose this keyboard activate control or another documented keyboard alternative, plus the authored instructions. These checks do not claim WCAG conformance.