`, 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

[{"_1":2,"_3":-5,"_4":-5},"loaderData",{"_5":6,"_7":8,"_9":10},"actionData","errors","root",{"_427":428,"_429":430},"routes/_app.x.$handle.$name",{"_11":12,"_13":14,"_15":16,"_18":19,"_17":-7,"_321":-5,"_20":322,"_22":323,"_324":325,"_326":327,"_26":328,"_24":329,"_330":-5,"_331":-5,"_332":52,"_333":334,"_335":43,"_336":-5,"_337":-5,"_338":339},"routes/_app.x.$handle.$name.branch.$branch.code.$",{"_11":12,"_13":14,"_15":16,"_17":-7,"_18":19,"_20":21,"_22":23,"_24":25,"_26":27,"_28":-5,"_29":-5,"_30":-5,"_31":-5,"_32":-5},"handle","dusty_medic","name","ekg-rhythm-practice","branchName","main","version","path","index.ts","project",{"_33":263,"_13":14,"_44":264,"_265":-5,"_266":52,"_267":268,"_269":268,"_270":271,"_272":-5,"_273":274,"_275":36,"_276":43,"_277":-5,"_278":-5,"_279":69,"_280":281,"_282":283,"_284":285,"_286":287,"_288":-5,"_289":290,"_291":290,"_292":293,"_294":293,"_295":293,"_296":290,"_297":290,"_298":299,"_300":301,"_302":303,"_304":52},"tree",[55,56,57,58,59],"file",{"_33":34,"_13":19,"_35":36,"_37":-5,"_38":39,"_40":41,"_42":43,"_44":45,"_17":46,"_47":48,"_49":50,"_51":52,"_53":-5,"_18":54},"contents",[],"upstream","pull","ahead","behind","envVars","id","c8981a8a-0dce-4c7c-b2d8-ccf1d1437db7","fileId","01a0633c-efa7-770e-92de-fcbd716f9193","parentId","branchId","7029bff5-bb8a-442e-a4f2-805f0156bd56","branchVersion",38,"latest",true,"createdAt",["D",1788376361503],4,"fileType","http","content","import { parseVal, serveImmutableFile } from \"https://esm.town/v/std/utils/index.ts\";\nimport { Hono } from \"npm:hono\";\nimport { Root } from \"./frontend/root.tsx\";\nimport { RHYTHMS } from \"./backend/rhythms-data.ts\";\nimport { TWELVE_LEAD_CASES } from \"./backend/twelve-lead-data.ts\";\n\nconst app = new Hono();\n\n// Serve the (never-cached) HTML shell at the root /\napp.get(\"/\", (c) => c.html(Root()));\n\n// Serve frontend files at the version-addressed URLs Root() stamps, cached immutably\napp.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path));\n\n// View source redirect\napp.get(\"/source\", (c) => c.redirect(parseVal().links.self.val));\n\n// List all rhythms (summary only — no questions in the payload).\n// Every rhythm is unlocked content-wise; the free/Pro split is now a daily\n// practice cap enforced client-side, not a content paywall.\napp.get(\"/api/rhythms\", (c) => {\n const list = [...RHYTHMS]\n .sort((a, b) => a.sortOrder - b.sortOrder)\n .map(({ questions, ...summary }) => ({\n ...summary,\n locked: false,\n questionCount: questions.length,\n }));\n return c.json(list);\n});\n\n// Single rhythm detail — full content, including quiz questions, for everyone.\napp.get(\"/api/rhythms/:id\", (c) => {\n const rhythm = RHYTHMS.find((r) => r.id === c.req.param(\"id\"));\n if (!rhythm) return c.json({ error: \"not found\" }, 404);\n return c.json({\n ...rhythm,\n locked: false,\n });\n});\n\n// List all 12-lead cases (summary only — leadFindings + questions omitted).\napp.get(\"/api/twelve-lead\", (c) => {\n const list = [...TWELVE_LEAD_CASES]\n .sort((a, b) => a.sortOrder - b.sortOrder)\n .map(({ leadFindings, questions, ...summary }) => ({\n ...summary,\n questionCount: questions.length,\n }));\n return c.json(list);\n});\n\n// Single 12-lead case detail — full content, including per-lead findings and quiz questions.\napp.get(\"/api/twelve-lead/:id\", (c) => {\n const twelveLead = TWELVE_LEAD_CASES.find((t) => t.id === c.req.param(\"id\"));\n if (!twelveLead) return c.json({ error: \"not found\" }, 404);\n return c.json(twelveLead);\n});\n\n// Unwrap and rethrow Hono errors as the original error\n// If you delete this, all errors will be \"Internal Server Error\"\napp.onError((err) => Promise.reject(err));\n\n// HTTP vals expect an exported \"fetch handler\"\n// This is how you \"run the server\" in Val Town with Hono\nexport default app.fetch;\n","deleted",false,"label",[19],{"_33":239,"_13":240,"_35":241,"_37":-5,"_38":39,"_40":97,"_42":43,"_44":242,"_17":69,"_47":84,"_49":-5,"_51":52,"_53":-5,"_61":243,"_18":244},{"_33":80,"_13":81,"_35":82,"_37":-5,"_38":39,"_40":67,"_42":43,"_44":83,"_17":69,"_47":84,"_49":-5,"_51":52,"_53":-5,"_61":85,"_18":86},{"_33":73,"_13":74,"_35":75,"_37":-5,"_38":39,"_40":67,"_42":43,"_44":76,"_17":69,"_47":24,"_49":77,"_51":52,"_53":-5,"_61":78,"_18":79},{"_33":64,"_13":65,"_35":66,"_37":-5,"_38":39,"_40":67,"_42":43,"_44":68,"_17":69,"_47":24,"_49":70,"_51":52,"_53":-5,"_61":71,"_18":72},{"_33":34,"_13":19,"_35":36,"_37":-5,"_38":39,"_40":41,"_42":43,"_44":60,"_17":46,"_47":48,"_49":50,"_51":52,"_53":-5,"_61":62,"_18":63},["D",1788376361503],"children",[],[19],"f174df99-6739-437c-b218-528fe54153d7","README.md","01a0633c-efa7-770e-92de-f8c87a88692d",1,["D",1788371332863],0,"# 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",[],[65],"4d03780d-716e-4f3b-9cdf-f3d72852a379","CHANGELOG.md","01a0633c-efa7-770e-92de-f742abd282c5",["D",1788371332863],"# 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