`, 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",{"_303":304,"_305":306},"routes/_app.x.$handle.$name",{"_11":12,"_13":14,"_15":-7,"_18":19,"_17":-7,"_227":-5,"_20":228,"_22":229,"_230":231,"_232":233,"_26":234,"_24":235,"_236":-5,"_237":-5,"_238":52,"_239":240,"_241":43,"_242":-5,"_243":-5,"_244":245},"routes/_app.x.$handle.$name.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","juniorsainte","name","reality-camera-studio","branchName","main","version","path","index.ts","project",{"_33":169,"_13":14,"_44":170,"_171":-5,"_172":52,"_173":174,"_175":174,"_176":177,"_178":-5,"_179":180,"_181":36,"_182":43,"_183":-5,"_184":-5,"_185":69,"_186":187,"_188":189,"_190":191,"_192":193,"_194":-5,"_195":196,"_197":196,"_198":199,"_200":199,"_201":199,"_202":196,"_203":196,"_204":205,"_206":207,"_208":209,"_210":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","a51ecff7-e0cd-4439-bdf0-aecb9752011e","fileId","01a0aa9e-8d5a-722e-8769-8ed17bf83441","parentId","branchId","a7613ece-a578-4724-aebc-be9a4598ab48","branchVersion",6,"latest",true,"createdAt",["D",1789569289800],2,"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 { compileShot } from \"./lib/engine.ts\";\nimport { submitKlingJob } from \"./lib/kling.ts\";\nimport { createGeneration, listGenerations } from \"./lib/db.ts\";\n\nconst app = new Hono();\napp.get(\"/\", (c) => c.html(Root()));\napp.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path));\napp.get(\"/source\", (c) => c.redirect(parseVal().links.self.val));\n\napp.get(\"/api/health\", async (c) => c.json({ ok: true, service: \"reality-camera-studio\", provider: \"kling\", ready: Boolean(Deno.env.get(\"KLING_API_KEY\")) }));\napp.get(\"/api/generations\", async (c) => c.json({ ok: true, generations: await listGenerations() }));\n\napp.post(\"/api/generate\", async (c) => {\n const body = await c.req.json().catch(() => ({}));\n const spec = {\n prompt: typeof body.prompt === \"string\" ? body.prompt : \"\",\n mode: body.mode === \"video\" ? \"video\" : \"image\",\n aspect: typeof body.aspect === \"string\" ? body.aspect : \"9:16\",\n duration: Number.isFinite(Number(body.duration)) ? Math.max(1, Math.min(20, Number(body.duration))) : 5,\n lens: Number.isFinite(Number(body.lens)) ? Math.max(14, Math.min(200, Number(body.lens))) : 50,\n aperture: Number.isFinite(Number(body.aperture)) ? Math.max(1.2, Math.min(22, Number(body.aperture))) : 2.8,\n iso: Number.isFinite(Number(body.iso)) ? Math.max(50, Math.min(12800, Number(body.iso))) : 400,\n shutter: typeof body.shutter === \"string\" ? body.shutter : \"1/120\",\n realism: Number.isFinite(Number(body.realism)) ? Math.max(70, Math.min(100, Number(body.realism))) : 95,\n motion: Number.isFinite(Number(body.motion)) ? Math.max(0, Math.min(100, Number(body.motion))) : 45,\n reference: Boolean(body.reference),\n } as const;\n const plan = compileShot(spec);\n if (plan.warnings.length) return c.json({ ok: false, error: plan.warnings.join(\" \") }, 400);\n\n const negativePrompt = \"plastic skin, beauty filter, over-smoothing, fake eyes, deformed hands, extra fingers, duplicated objects, floating objects, texture repetition, temporal flicker, inconsistent shadows, unnatural motion, excessive sharpening, artificial glow, fake depth of field\";\n const result = await submitKlingJob({\n prompt: `${plan.scene}. Capture it as a real physical scene. Natural human behavior, real materials, realistic light transport, authentic camera response. ${plan.antiArtificiality.join(\", \")}.`,\n mode: spec.mode,\n aspect: spec.aspect,\n duration: spec.duration,\n negativePrompt,\n referenceUrl: typeof body.referenceUrl === \"string\" ? body.referenceUrl : undefined,\n camera: plan.camera,\n });\n\n const id = await createGeneration({\n mode: spec.mode,\n prompt: spec.prompt,\n status: result.status,\n provider: \"kling\",\n providerData: result,\n });\n return c.json({ ok: result.status !== \"provider_error\", generationId: id, plan, result });\n});\n\napp.post(\"/api/compile\", async (c) => {\n const body = await c.req.json().catch(() => ({}));\n const spec = {\n prompt: typeof body.prompt === \"string\" ? body.prompt : \"\",\n mode: body.mode === \"video\" ? \"video\" : \"image\",\n aspect: typeof body.aspect === \"string\" ? body.aspect : \"9:16\",\n duration: Number.isFinite(Number(body.duration)) ? Math.max(1, Math.min(20, Number(body.duration))) : 5,\n lens: Number.isFinite(Number(body.lens)) ? Math.max(14, Math.min(200, Number(body.lens))) : 50,\n aperture: Number.isFinite(Number(body.aperture)) ? Math.max(1.2, Math.min(22, Number(body.aperture))) : 2.8,\n iso: Number.isFinite(Number(body.iso)) ? Math.max(50, Math.min(12800, Number(body.iso))) : 400,\n shutter: typeof body.shutter === \"string\" ? body.shutter : \"1/120\",\n realism: Number.isFinite(Number(body.realism)) ? Math.max(70, Math.min(100, Number(body.realism))) : 95,\n motion: Number.isFinite(Number(body.motion)) ? Math.max(0, Math.min(100, Number(body.motion))) : 45,\n reference: Boolean(body.reference),\n } as const;\n return c.json(compileShot(spec));\n});\n\napp.onError((err) => Promise.reject(err));\nexport default app.fetch;\n","deleted",false,"label",[19],{"_33":114,"_13":115,"_35":116,"_37":-5,"_38":39,"_40":67,"_42":43,"_44":117,"_17":69,"_47":84,"_49":-5,"_51":52,"_53":-5,"_61":118,"_18":119},{"_33":80,"_13":81,"_35":82,"_37":-5,"_38":39,"_40":46,"_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",1789569289800],"children",[],[19],"376b80e5-7c37-45a8-a51a-e562c9406fbb","README.md","01a0aa9e-8d5a-722e-8769-8ac07fe559cb",1,["D",1789568911615],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],"4ff7678a-ba44-4ba0-a0de-8d0c28ac3037","CHANGELOG.md","01a0aa9e-8d5a-722e-8769-8400a3ccb6a2",["D",1789568911615],"# 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