`, 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",{"_270":271,"_272":273},"routes/_app.x.$handle.$name",{"_105":104,"_37":50,"_113":95,"_32":114,"_13":14,"_115":-5,"_11":116,"_117":118,"_119":120,"_121":122,"_123":124,"_26":-5,"_125":-5,"_126":-5,"_127":30,"_128":129,"_130":64,"_131":-5,"_132":-5,"_133":134},"routes/_app.x.$handle.$name.branch.$branch.version.$version.diff",{"_11":12,"_13":14,"_15":16,"_17":18,"_19":-5},"project",{"_48":49,"_37":50,"_43":51,"_52":-5,"_53":30,"_54":55,"_56":55,"_57":58,"_59":-5,"_19":60,"_61":62,"_63":64,"_65":-5,"_66":-5,"_67":68,"_69":70,"_71":72,"_73":74,"_75":76,"_77":-5,"_78":79,"_80":79,"_81":82,"_83":82,"_84":82,"_85":79,"_86":79,"_87":88,"_89":90,"_91":92,"_93":30},"version",3,"changes",[25],"aiChatInfo",{"_20":21,"_22":-5,"_23":-5,"_24":-5},"userId","aiChatMessageId","480338a4-3546-4ee8-b229-b31706b94650","aiChatThreadId","aiChatThreadUserId","aiChatThreadTitle",{"_26":27,"_28":-7,"_29":30,"_31":30,"_32":33,"_34":33},"file",{"_35":36,"_37":38,"_39":40,"_41":42,"_43":44,"_45":14,"_46":47,"_29":30},"previous","deleted",false,"deletedHere","path","lib/spotify.ts","latestPath","fileId","f92b6ebe-9e49-11f1-b31f-1607ee4eb77e","name","spotify.ts","fileType","script","content","import { StoredUser, upsertUser } from \"./db.ts\";\n\nconst CLIENT_ID = Deno.env.get(\"SPOTIFY_CLIENT_ID\") ?? \"\";\nconst CLIENT_SECRET = Deno.env.get(\"SPOTIFY_CLIENT_SECRET\") ?? \"\";\nexport const REDIRECT_URI = Deno.env.get(\"SPOTIFY_REDIRECT_URI\") ??\n \"https://discovery-radar.val.run/auth/callback\";\n\nconst SCOPES = [\n \"user-top-read\", // top artists/tracks (taste)\n \"user-read-private\",\n \"user-read-email\",\n \"user-read-recently-played\",\n \"user-follow-read\", // followed artists (novelty filtering)\n \"playlist-modify-private\",\n \"playlist-modify-public\",\n].join(\" \");\n\nexport interface Tokens {\n access_token: string;\n refresh_token?: string;\n expires_in: number;\n}\n\nfunction basicAuth(): string {\n return \"Basic \" + btoa(`${CLIENT_ID}:${CLIENT_SECRET}`);\n}\n\nexport function authorizeUrl(state: string): string {\n const p = new URLSearchParams({\n client_id: CLIENT_ID,\n response_type: \"code\",\n redirect_uri: REDIRECT_URI,\n scope: SCOPES,\n state,\n show_dialog: \"true\",\n });\n return `https://accounts.spotify.com/authorize?${p.toString()}`;\n}\n\nexport async function exchangeCode(code: string): Promise {\n const body = new URLSearchParams({\n grant_type: \"authorization_code\",\n code,\n redirect_uri: REDIRECT_URI,\n });\n return tokenRequest(body);\n}\n\nexport async function refreshTokens(refreshToken: string): Promise {\n const body = new URLSearchParams({\n grant_type: \"refresh_token\",\n refresh_token: refreshToken,\n });\n return tokenRequest(body);\n}\n\nasync function tokenRequest(body: URLSearchParams): Promise {\n const res = await fetch(\"https://accounts.spotify.com/api/token\", {\n method: \"POST\",\n headers: {\n \"content-type\": \"application/x-www-form-urlencoded\",\n authorization: basicAuth(),\n },\n body,\n });\n if (!res.ok) {\n throw new Error(`Spotify token error ${res.status}: ${await res.text()}`);\n }\n return res.json();\n}\n\n/**\n * Authenticated call to api.spotify.com. Handles access-token refresh and a\n * single 401 retry. The `user` object is mutated on refresh so callers see\n * the new token too.\n */\nexport async function api(\n user: StoredUser,\n path: string,\n opts: { method?: string; body?: unknown } = {},\n): Promise {\n if (Date.now() > user.expiresAt - 30_000) {\n const fresh = await refreshTokens(user.refreshToken);\n user.accessToken = fresh.access_token;\n user.expiresAt = Date.now() + fresh.expires_in * 1000;\n await upsertUser(user);\n }\n\n const call = (token: string) =>\n fetch(`https://api.spotify.com/v1/${path}`, {\n method: opts.method ?? \"GET\",\n headers: {\n authorization: `Bearer ${token}`,\n \"content-type\": \"application/json\",\n },\n body: opts.body ? JSON.stringify(opts.body) : undefined,\n });\n\n let res = await call(user.accessToken);\n if (res.status === 401) {\n const fresh = await refreshTokens(user.refreshToken);\n user.accessToken = fresh.access_token;\n user.expiresAt = Date.now() + fresh.expires_in * 1000;\n await upsertUser(user);\n res = await call(user.accessToken);\n }\n if (!res.ok) {\n throw new Error(`Spotify API ${res.status} on ${path}: ${await res.text()}`);\n }\n if (res.status === 204) return undefined as T;\n return res.json();\n}\n","createdAt",["D",1787417597529],"branchVersion","branchId","dc1f9fe4-aa8c-400d-87f3-9d22e6847153","id","f8c773d7-7a4a-4d5b-84e7-ccf2b3929d80","discovery-radar",["D",1787417498284],"deletedAt","legacyEnvVars","privacy","public","httpPrivacy","description","Spotify discovery with taste radar + weekly playlist refresh","imageUrl","e6d51557-2988-4ce3-bf61-63d827903a6c","pinnedFileId","01a02a62-92f6-771d-907a-be2483e744c9","pinPreview",true,"pinMigrated","screenshotVersion","likeCount",0,"orgId","3ebf4d50-fe40-465b-915c-bd543c8a8608","tursoName","f8c773d77a4a4d5b84e7ccf2b3929d80","tursoHostname","f8c773d77a4a4d5b84e7ccf2b3929d80-val-town.aws-us-east-2.turso.io","tursoMeasuredAt",["D",1789502486629],"pinned","userPerm","r","valPerm","blobPerm","rw","emailPerm","sqlitePerm","projectPerm","telemetryPerm","user",{"_105":104,"_112":108},"org",{"_105":104,"_106":-5,"_107":108,"_19":60,"_109":110,"_111":30},"branch",{"_13":94,"_37":95,"_48":47,"_96":49,"_97":-5,"_98":-5,"_99":-5,"_100":-5,"_101":-5,"_102":50,"_103":104},"isOwned",90,"main","projectId","forkedBranchId","forkedBranchVersion","forkedProjectPrivacy","forkedProjectId","forkedProjectOrgId","projectName","userHandle","test_account_001","handle","displayName","avatar","https://img.clerk.com/eyJ0eXBlIjoiZGVmYXVsdCIsImlpZCI6Imluc18yTm10cGhQUklwU0tqZHNiOHNnNGd2ZjJURFUiLCJyaWQiOiJ1c2VyXzJabHpKOGNWSmhqcWduM3VVV0xTUGlicVprayJ9","tier","free","canRestrictVals","profileImageUrl","branchName","","adoptOrgId",{"_48":49,"_37":50,"_43":265,"_52":-5,"_53":30,"_54":55,"_56":55,"_57":58,"_59":-5,"_19":60,"_61":62,"_63":64,"_65":-5,"_66":-5,"_67":68,"_69":70,"_71":72,"_73":74,"_75":266,"_77":-5,"_78":79,"_80":79,"_81":82,"_83":82,"_84":82,"_85":79,"_86":79,"_87":267,"_89":268,"_91":269,"_93":30},"tree",[184,191,194,195,196],"files",[184,185,186,187,188,189,190,191,192,193,194,195,196],"counts",{"_174":68,"_175":143,"_176":68,"_177":178,"_179":180},"contents",[135,136,137,138,139],"upstreamProject","upstreamBranch","emptyEnvVars","flags",[],"hasHttpFiles","grants","orgs","customDomains",{},{"_48":169,"_37":170,"_35":171,"_142":-5,"_46":47,"_45":143,"_144":64,"_43":172,"_13":68,"_39":167,"_41":-5,"_29":30,"_148":-5,"_32":173},{"_48":162,"_37":163,"_35":164,"_142":-5,"_46":47,"_45":165,"_144":64,"_43":166,"_13":68,"_39":167,"_41":-5,"_29":30,"_148":-5,"_32":168},{"_48":156,"_37":157,"_35":158,"_142":-5,"_46":47,"_45":143,"_144":64,"_43":159,"_13":68,"_39":26,"_41":160,"_29":30,"_148":-5,"_32":161},{"_48":150,"_37":151,"_35":152,"_142":-5,"_46":47,"_45":143,"_144":30,"_43":153,"_13":68,"_39":26,"_41":154,"_29":30,"_148":-5,"_32":155},{"_48":140,"_37":141,"_35":62,"_142":-5,"_46":47,"_45":143,"_144":30,"_43":145,"_13":68,"_39":146,"_41":147,"_29":30,"_148":50,"_32":149},"299e3856-df3c-4850-8286-52ae4230c437","index.ts","parentId",1,"latest",["D",1787417498284],"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\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// Add your API routes here\n// app.get(\"/api/data\", c => c.json({ hello: \"world\" }));\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","label",[141],"34aeff79-67ed-4234-85dd-0f01ebb01f91","README.md","01a02a62-92f6-771d-907a-b81da57860c2",["D",1787417498284],"# 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",[151],"4fe8db74-919d-4686-9be5-883aad74c74f","CHANGELOG.md","01a02a62-92f6-771d-907a-b61ebd4f10fe",["D",1787417498284],"# 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

Diff · v3