`, favicon, and body of `Root()` to\nmatch your app's existing `index.html`, and stamp anything else your shell\nreferences directly (images, css) with `immutableFileUrl()`.\n\n1. Create `frontend/root.tsx`:\n\n```tsx\n/** @jsxImportSource npm:hono@4/jsx */\nimport { raw } from \"npm:hono@4/html\";\nimport { immutableFileUrl } from \"https://esm.town/v/std/utils/index.ts\";\n\n// The HTML shell for the app. It is never cached, so immutableFileUrl can stamp\n// the current val version into each asset URL — the browser caches those\n// immutably, and publishing the val changes the URLs, refetching exactly once.\nexport function Root() {\n return (\n <>\n {raw(\"<!DOCTYPE html>\")}\n <html lang=\"en\">\n <head>\n <meta charSet=\"UTF-8\" />\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\" />\n <title>React Hono Val Town Starter

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caches.match(\"/\") : new Response(\"Offline\", { status: 503, statusText: \"Offline\" }))));\n});\n","createdAt",["D",1787980986815],"branchVersion","branchId","91efcfc2-57fc-4e40-a802-a0a982202b7c","id","b7e65ae6-0a45-4ddf-9a18-259d42abc50b","polyatomics",["D",1787973066715],"deletedAt","legacyEnvVars",false,"privacy","public","httpPrivacy","description","Practice polyatomic ion formulas and charges","imageUrl","a0dbc0e3-e526-4d2e-b19c-fcb458a27a4e","pinnedFileId","01a04b7f-e043-776f-9b1e-67170ce79a7b","pinPreview","pinMigrated","screenshotVersion","likeCount",0,"orgId","01a04933-e278-70de-a7be-b64137dd639b","tursoName","b7e65ae60a454ddf9a18259d42abc50b","tursoHostname","b7e65ae60a454ddf9a18259d42abc50b-val-town.aws-us-east-2.turso.io","tursoMeasuredAt",["D",1789535451117],"pinned","userPerm","r","valPerm","blobPerm","rw","emailPerm","sqlitePerm","projectPerm","telemetryPerm","user",{"_100":99,"_108":104},"org",{"_100":99,"_101":102,"_103":104,"_18":56,"_105":106,"_107":49},"branch",{"_13":89,"_32":90,"_43":42,"_91":44,"_92":-5,"_93":-5,"_94":-5,"_95":-5,"_96":-5,"_97":45,"_98":99},"isOwned",242,"main","projectId","forkedBranchId","forkedBranchVersion","forkedProjectPrivacy","forkedProjectId","forkedProjectOrgId","projectName","userHandle","altors_graphika","handle","displayName","Altors-Graphika","avatar","https://imagedelivery.net/iHX6Ovru0O7AjmyT5yZRoA/d88c49d9-df42-4251-2a99-48ca93b86e01/square512?exp=1789552799&sig=bf0757f1d31686754a686b3d34af7aeedeaab34bbbbebae9b7c24c998dd2c7b4","tier","free","canRestrictVals","profileImageUrl","branchName","","adoptOrgId",{"_43":44,"_32":45,"_38":280,"_47":-5,"_48":49,"_50":51,"_52":51,"_53":54,"_55":-5,"_18":56,"_57":58,"_59":25,"_60":-5,"_61":-5,"_62":63,"_64":65,"_66":67,"_68":69,"_70":281,"_72":-5,"_73":74,"_75":74,"_76":77,"_78":77,"_79":77,"_80":74,"_81":74,"_82":282,"_84":283,"_86":284,"_88":49},"tree",[175,186,187,188],"files",[175,176,177,178,179,180,181,182,183,184,185,186,187,188],"counts",{"_165":63,"_166":149,"_167":63,"_168":169,"_170":171},"contents",[131,132,133,134],"upstreamProject","upstreamBranch","emptyEnvVars","flags",[],"hasHttpFiles","grants","orgs","customDomains",{},{"_43":159,"_32":160,"_30":161,"_137":-5,"_41":42,"_40":149,"_139":25,"_38":162,"_13":63,"_34":163,"_36":-5,"_24":49,"_144":-5,"_27":164},{"_43":153,"_32":154,"_30":155,"_137":-5,"_41":42,"_40":149,"_139":49,"_38":156,"_13":63,"_34":20,"_36":157,"_24":49,"_144":-5,"_27":158},{"_43":146,"_32":147,"_30":148,"_137":-5,"_41":42,"_40":149,"_139":49,"_38":150,"_13":63,"_34":20,"_36":151,"_24":49,"_144":-5,"_27":152},{"_43":135,"_32":136,"_30":58,"_137":-5,"_41":42,"_40":138,"_139":49,"_38":140,"_13":141,"_34":142,"_36":143,"_24":49,"_144":45,"_27":145},"9810e306-2f7d-4471-abdd-8f1231d40f76","index.ts","parentId",54,"latest",["D",1787980977902],3,"http","import { parseVal, serveImmutableFile } from \"https://esm.town/v/std/utils/index.ts\";\nimport { Hono } from \"npm:hono\";\nimport { Root } from \"./frontend/root.tsx\";\n\nconst app = new Hono();\n\napp.get(\"/\", (c) => c.html(Root()));\napp.get(\"/sw.js\", (c) => c.body(`const CACHE = \"polyatomics-v1\";\\nconst SHELL = [\"/\"];\\nself.addEventListener(\"install\", (event) => { event.waitUntil(caches.open(CACHE).then((cache) => cache.addAll(SHELL)).then(() => self.skipWaiting())); });\\nself.addEventListener(\"activate\", (event) => { event.waitUntil(caches.keys().then((keys) => Promise.all(keys.filter((key) => key !== CACHE).map((key) => caches.delete(key)))).then(() => self.clients.claim())); });\\nself.addEventListener(\"fetch\", (event) => { const request = event.request; if (request.method !== \"GET\") return; event.respondWith(caches.match(request).then((cached) => cached || fetch(request).then((response) => { if (response.ok || response.type === \"opaque\") { const copy = response.clone(); caches.open(CACHE).then((cache) => cache.put(request, copy)); } return response; }).catch(() => request.mode === \"navigate\" ? caches.match(\"/\") : new Response(\"Offline\", { status: 503, statusText: \"Offline\" })))); });`, 200, { \"Content-Type\": \"application/javascript; charset=UTF-8\", \"Cache-Control\": \"no-cache\" }));\napp.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path));\napp.get(\"/source\", (c) => c.redirect(parseVal().links.self.val));\napp.onError((err) => Promise.reject(err));\n\nexport default app.fetch;\n","label",[136],"ddc42079-4ac9-4955-8cba-fc0870e3ce3c","README.md","01a04b7f-e043-776f-9b1e-61c237442125",1,["D",1787973066715],"# React + Hono Starter\n\nA minimal starter template for building client-side React apps with a Hono\nbackend on Val Town. Click **Remix** to get your own copy.\n\n## Picking a starter\n\n| Starter | When to pick it |\n| --- | --- |\n| [`basic-html-starter`](https://www.val.town/x/templates/basic-html-starter) | Static HTML pages. Sprinkle of vanilla JS. No server-side rendering. |\n| [`hono-jsx-starter`](https://www.val.town/x/templates/hono-jsx-starter) | Dynamic server-rendered HTML with JSX. API routes. No React, no SPA. |\n| **[`react-hono-starter`](https://www.val.town/x/templates/react-hono-starter)** *(you're here)* | Client-side React SPA with a Hono API backend. |\n\n**Want to build UI?** Start writing React components in\n[`frontend/components/`](/frontend/components/). Import them into `App.tsx` and\nyou're good to go. Styling is [Twind](https://twind.style/) — just use Tailwind\nutility classes, zero config.\n\n**Want to add an API?** Add routes in [`index.ts`](/index.ts) (there's a\ncommented-out example). Fetch them from your React components.\n\n## Architecture\n\n```mermaid\ngraph LR\n Browser -->|\"GET /\"| Hono[\"index.ts
(Hono server)\"]\n Hono -->|serves| HTML[\"root.tsx\"]\n HTML -->|loads| Entry[\"index.tsx\"]\n Entry -->|renders| App[\"App.tsx\"]\n App -->|renders| Counter[\"Counter.tsx\"]\n```\n\n## File structure\n\n```\nindex.ts ← Hono backend (serves frontend + API routes)\nfrontend/\n root.tsx ← HTML shell (stamps immutable asset URLs)\n index.tsx ← React entrypoint (mounts )\n favicon.svg ← App icon\n components/\n App.tsx ← Root component (layout + view source link)\n Counter.tsx ← Example component with state\n```\n\n## How it works\n\n1. **`index.ts`** is the HTTP entrypoint — a Hono server that serves the\n frontend and any API routes you add.\n2. **`frontend/root.tsx`** is the HTML shell — it loads Twind and stamps\n immutable asset URLs for the favicon and React entrypoint.\n3. **`frontend/index.tsx`** mounts the React app.\n4. **`frontend/components/App.tsx`** is the root layout — add new components\n alongside it.\n5. **`frontend/components/Counter.tsx`** is an example stateful component —\n replace it with your own!\n\n## Next steps\n\n- Add API routes in `index.ts`\n- Add new components in `frontend/components/`\n- Add a SQLite database — see the\n [React Hono Example](https://www.val.town/x/stevekrouse/reactHonoExample) for\n a full-stack example with database, queries, and shared types\n\nTemplate updates and upgrade paths for existing remixes: [CHANGELOG.md](/CHANGELOG.md)\n",[147],"2f8efb19-122b-4b2a-87f5-04cb543486ff","CHANGELOG.md","01a04b7f-e043-776f-9b1e-5cae9d820f79",["D",1787973066715],"# Changelog\n\n## 2026-07-30 — Immutable asset caching\n\nFrontend files are now served at version-addressed URLs\n(`/__immutable/45/frontend/index.tsx`) with\n`Cache-Control: public, max-age=31536000, immutable`, so repeat visits load the\nwhole client graph from the browser cache — roughly 3× faster (~665ms → ~157ms\nmeasured). Publishing your val bumps its version, which changes every URL, so\ncaches invalidate automatically. Old-version URLs return 404 after a publish\n(like Next.js build assets); a reload picks up the new version.\n\nWhat changed in the template:\n\n- `frontend/index.html` → [`frontend/root.tsx`](/frontend/root.tsx): the HTML\n shell is now JSX and stamps asset URLs with `immutableFileUrl()`\n- [`index.ts`](/index.ts): serves `Root()` at `/`, and one\n `app.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path))` route\n serves all frontend files\n\n### Upgrading an existing remix\n\nYour copy of this template doesn't update automatically. Two options:\n\n**Minimal (most of the benefit):** point both routes at `serveImmutableFile` —\nyour existing bare URLs redirect into versioned space, the new route serves\nthem, and the whole module graph gets cached (costs one redirect per page view):\n\n```ts\nimport { serveImmutableFile } from \"https://esm.town/v/std/utils/index.ts\";\n\napp.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path));\napp.get(\"/frontend/**/*\", (c) => serveImmutableFile(c.req.path)); // was serveFile\n```\n\n**Full upgrade (also removes the redirect):** three self-contained steps —\nno other files needed. Adjust the ``, favicon, and body of `Root()` to\nmatch your app's existing `index.html`, and stamp anything else your shell\nreferences directly (images, css) with `immutableFileUrl()`.\n\n1. Create `frontend/root.tsx`:\n\n```tsx\n/** @jsxImportSource npm:hono@4/jsx */\nimport { raw } from \"npm:hono@4/html\";\nimport { immutableFileUrl } from \"https://esm.town/v/std/utils/index.ts\";\n\n// The HTML shell for the app. It is never cached, so immutableFileUrl can stamp\n// the current val version into each asset URL — the browser caches those\n// immutably, and publishing the val changes the URLs, refetching exactly once.\nexport function Root() {\n return (\n <>\n {raw(\"<!DOCTYPE html>\")}\n <html lang=\"en\">\n <head>\n <meta charSet=\"UTF-8\" />\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\" />\n <title>React Hono Val Town Starter\n

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