Historical record: this page archives the 0.40.x → 0.41/0.42 migrations, written for the retired runtime-authoring line. The current line (v0.44.0-beta.1) is consumed fresh through @openelement/create — there is no supported 0.43 → 0.44 in-place upgrade. New projects start from the current starter and the getting-started guide.

0.41.x → 0.42

The stable 0.42 line added request-time surfaces — loaders, actions, progressive-enhancement forms, redirects and Nitro server output. Static-first sites upgraded without a breaking change to the frozen 0.41 surface. ADR-0122 records the accepted 0.42.0 contract.

From 0.40.x

The consumer graph is five packages; core/signal/router/protocol/content/ssg are retired. Author with defineElement/definePage/defineApp and build with buildApp(). defineLayout is removed; distribution is npm-first.

Alpha.17–19

Build helpers moved to element/build-utils; router types left the app root; renderIntent.streaming was removed; dynamic 500s fail builds by default; star-seam types (SafeHtml/UnsafeHtml/StyleSheetRule) left the element root; ui controls are squared (radius-1).

The 0.41.0 freeze

Adapter-vite internal subpaths (app-vite, build-context, head-injection, i18n-plugin, plugin, generated-data-resolver, plugin-mdx, route-manifest, cli/build-client, cli/build-ssg) were pruned. Use the root, nitro-mount, cli/build and sitemap.

Verify after upgrading

Reinstall frozen, rebuild, and grep for removed imports: renderIntent.streaming, open-element-render, open-element-hydration, app-vite, SafeHtml, *TagName. Re-record visual baselines after the ui geometry change.

The complete entry-by-entry guide with before/after imports lives in docs/release/v0.41.0-migration.md.