Lessons

What it actually took to wire SvelteKit 3 RC + Vite+ + Cloudflare together. Useful if you're extending this — human or agent.

SvelteKit 3 (RC)

No svelte.config.js. Adapter and compiler options are passed inline to sveltekit() in vite.config.ts.
$lib is gone — it's #lib, a package.json imports subpath. An extensionless #lib/thing doesn't resolve inside .svelte files, so re-export everything through a src/lib/index.ts barrel and import #lib. Components and assets (which have extensions) can be imported directly: #lib/components/X.svelte.
$app/tsconfig is virtual — svelte-kit sync writes it to node_modules/$app/tsconfig.json. Anything that reads tsconfig.json outside the Vite pipeline (vp check, svelte-check) needs a svelte-kit sync first, hence "check": "svelte-kit sync && vp check".
The whole site is static, so src/routes/+layout.ts just does export const prerender = true.

No global vp needed. It's a dev dependency; the package.json scripts call it and pnpm resolves it from node_modules/.bin, so teammates only need Node and pnpm. (VoidZero's own templates assume a global vp — that also works, it's just not required.)
Config lives in vite.config.ts, in fmt / lint / test / check blocks — not .oxfmtrc / .oxlintrc. Use defineConfig from vite-plus.
Deduplicate Vite. SvelteKit's peers pull a real vite, while Vite+ wants @voidzero-dev/vite-plus-core. Left alone you get two. Fix: a pnpm-workspace.yaml override — 'vite@*': 'npm:@voidzero-dev/vite-plus-core@<v>' — plus keep vite as a dev dependency alias so pnpm has the edge. This is what vp migrate does.
Tests import from vite-plus/test, not vitest (not a direct dep) and not @voidzero-dev/vite-plus-test (removed in 0.3.x). You can drop the vitest dependency entirely.
vp check runs the tools directly, not through Vite — so it won't run svelte-kit sync for you.
Guard the SvelteKit plugin out of Vitest (process.env.VITEST) or you hit "The configured Vite SSR environment must be a RunnableDevEnvironment".

Settings moved from .npmrc / package.json#pnpm to pnpm-workspace.yaml.
onlyBuiltDependencies is now an allowBuilds: map (esbuild: true, …).
minimumReleaseAge blocks packages published in the last N minutes — a supply-chain guard. Set 0 to track newest; a real project wants 1440+.
On an Intel Mac, mise can't install pnpm 12 from the default (aqua) backend — no darwin-x64 build. Use "github:pnpm/pnpm".

Chose import.meta.glob('/src/content/*.md', { query: '?raw', eager: true }) + marked + a /^#\s+(.+)$/m title regex over Content Collections: no config file, no codegen step, no sync ordering. ~30 lines in src/lib/docs.ts.
These docs carry no frontmatter — the title comes from the H1, and nav order + card copy live in one NAV array. So the same file reads cleanly on GitHub and renders on the site.
If you do want frontmatter: gray-matter pulls a transitive direct eval (Rolldown warns). Use js-yaml's load on the --- block yourself instead.
Rendering happens at build time (pages are prerendered), so marked never reaches the client or the Worker.

@sveltejs/adapter-cloudflare writes .svelte-kit/cloudflare; wrangler.jsonc main + assets.directory point there.
worker-configuration.d.ts (from wrangler types) is committed so vp check is self-contained — re-run pnpm gen after editing wrangler.jsonc.

pnpm/action-setup + actions/setup-node (node-version-file: .node-version, cache: pnpm) is all the setup needed. Every step runs through pnpm run …, so no global tooling in CI either.