Next.js resilience work edges out SvelteKit quality-of-life improvements

Better resilience across the Next.js runtime

The dominant story this week is the steady hardening of Next.js's runtime behavior across three canary releases. Turbopack now retries chunk loading on failure, a meaningful change for production environments where transient network glitches can cause page crashes. The same release fixed dev-overlay hydration error ordering and upgraded React.

A more subtle but important fix came in canary.59: after(callback) will no longer fire after the response has ended, and request APIs in promises passed to after() inside actions and handlers now work correctly. For anyone using Next.js's deferred-response pattern, this addresses a class of bugs that have been difficult to diagnose. That release also enforced route segment configs on metadata routes under Cache Components and added verbose OTEL spans for the App Router.

On the tooling side, canary.57 fixed the dev-overlay open-in-editor path when using a src directory and scoped the cold cache indicator to shell cache misses. Canary.52 laid the groundwork for the future by adding experimental React compiler support to Turbopack and upgrading next-rspack to RSPack 2.0.

Rounding out the canary updates: a minor but pragmatic change makes the release train continue even when @next/swc-wasm-* packages fail to publish, and canary.53 polished the dev-overlay error header layout and instant-fix chip.

SvelteKit: smarter prerendering and form validation warnings

SvelteKit 2.66.0 brought two welcome quality-of-life improvements. Prerendered .md and .mdx files are now precompressed, reducing storage and bandwidth for documentation sites and content-driven apps. More helpfully for everyday development, the framework will warn when boolean inputs in form schemas aren't marked optional — a common gotcha that leads to unexpected validation errors. The release also fixed blur/focusout handler timing during navigation.

Three patch releases addressed adapter-specific issues: adapter-vercel prevents missing immutable assets from being cached as 404s for a year, adapter-cloudflare avoids type collisions with user-defined env properties, and adapter-node now logs its actual listening address and bundles entrypoints alongside app code. For the enhanced-img package, the EnhancedImgAttributes type is now exported and imports containing ? are excluded from transformation.

Expo EAS CLI: audit logs and non-interactive build improvements

EAS CLI shipped two updates. Version 20.2.0 added support for non-interactive iOS builds using the App Store Connect API key stored in EAS credentials — eliminating the need for EXPO_ASC_* environment variables — and enabled non-interactive update rollbacks. Version 20.3.0 introduced eas account:audit for viewing an account's audit logs and improved eas update:view to accept platform-specific update IDs.