Add initial llms.txt

Author: lucperkins

.npmrc

@@ -1,2 +1 @@
-auto-install-peers = true
 shamefully-hoist = true

package.json

@@ -34,6 +34,7 @@
     "astro-expressive-code": "^0.38.3",
     "astro-icon": "^1.1.5",
     "astro-seo": "^0.8.4",
+    "handlebars": "^4.7.8",
     "marked": "^12.0.2",
     "posthog-js": "^1.266.0",
     "react": "^18.3.1",

pnpm-lock.yaml

@@ -15,3 +15,11 @@ export const startPagePath = (slug: string): string => {
 const pagePath = (collection: string, slug: string): string => {
   return `/${collection}/${slug}`;
 };
+
+export const formatDate = (date: Date): string => {
+  return date.toLocaleDateString("en-us", {
+    year: "numeric",
+    month: "long",
+    day: "numeric",
+  });
+};

src/lib/utils.ts

@@ -0,0 +1,56 @@
+import { conceptPagePath, startPagePath } from "../lib/utils";
+import { site } from "../site";
+import type { APIRoute } from "astro";
+import { getCollection } from "astro:content";
+import Handlebars from "handlebars";
+import fs from "node:fs";
+import path from "node:path";
+
+const { url: root, title, description: tagline, llms } = site;
+
+const templateFile = fs.readFileSync(
+  path.join(process.cwd(), "src/templates/llms.txt.hbs"),
+  "utf-8",
+);
+
+const template = Handlebars.compile(templateFile);
+
+export const GET: APIRoute = async () => {
+  const startPages = await getCollection("start");
+  const conceptPages = await getCollection("concepts");
+
+  const content = template({
+    root,
+    title,
+    tagline,
+    description: llms.description,
+    startPages: startPages.map(({ data: { title }, slug }) => ({
+      title,
+      href: `${root}/${startPagePath(slug)}`,
+    })),
+    conceptPages: conceptPages.map(({ data: { title }, slug }) => ({
+      title,
+      href: `${root}/${conceptPagePath(slug)}`,
+    })),
+    otherFormats: [
+      {
+        root,
+        file: "llms-small.txt",
+        description: "compact structure-only version",
+      },
+      {
+        root,
+        file: "llms-full.txt",
+        description: "complete content in one file",
+      },
+    ],
+  });
+
+  return new Response(content, {
+    headers: {
+      "Content-Type": "text/plain; charset=utf-8",
+    },
+  });
+};
+
+export const prerender = true;

src/pages/llms.txt.ts

@@ -32,7 +32,11 @@ type Language =
 
 type Site = {
   title: string;
+  url: string;
   description: string;
+  llms: {
+    description: string;
+  };
   githubUrl: string;
   languages: Language[];
   defaultLanguage: Language;
@@ -49,7 +53,12 @@ type Site = {
 
 export const site: Site = {
   title: "Zero to Nix",
+  url: "https://zero-to-nix.com",
   description: "Your guide to learning Nix and flakes",
+  llms: {
+    description:
+      "Zero to Nix is an opinionated learning resource for Nix created by [Determinate Systems](https://determinate.systems/llms.txt). It takes you on a [learning journey](#start-pages) from installing Nix to exploring Nix development environments to building Nix packages and more. It also offers a series of [concept pages](#concept-pages) covering some of the trickier corners of Nix.",
+  },
   githubUrl: "https://github.com/DeterminateSystems/zero-to-nix",
   languages: ["C++", "Go", "Haskell", "JavaScript", "Python", "Rust", "Scala"],
   defaultLanguage: "JavaScript",

src/site.ts

@@ -0,0 +1,25 @@
+# {{title}}
+
+> {{tagline}}
+
+{{description}}
+
+## Start pages
+
+{{#each startPages}}
+- [{{this.title}}]({{this.href}})
+{{/each}}
+
+## Concept pages
+
+{{#each conceptPages}}
+- [{{this.title}}]({{this.href}})
+{{/each}}
+
+## Other formats
+
+For more detailed documentation, see also:
+
+{{#each otherFormats}}
+- [`{{this.file}}`]({{root}}/{{this.file}}) ({{this.description}})
+{{/each}}