seo: sitemap, robots, og tags

frontend/src/app/layout.tsx

@@ -7,10 +7,40 @@ import "@fontsource/inter/700.css";
 import { Providers } from "./providers";
 import "./globals.css";
 
+const siteUrl = process.env.NEXT_PUBLIC_SITE_URL || "https://codetutor.example.com";
+
 export const metadata: Metadata = {
-  title: "CodeTutor - Coding Interview Preparation",
+  title: {
+    default: "CodeTutor - Coding Interview Preparation",
+    template: "%s | CodeTutor",
+  },
   description:
-    "Master coding interviews with curated questions, detailed explanations, and optimal solutions.",
+    "Master coding interviews with curated questions, detailed explanations, and optimal solutions. Practice 400+ problems with interactive code editor.",
+  keywords: [
+    "coding interview",
+    "leetcode",
+    "algorithm",
+    "data structures",
+    "programming practice",
+    "software engineering",
+  ],
+  authors: [{ name: "Kai Chappell" }],
+  openGraph: {
+    type: "website",
+    locale: "en_US",
+    url: siteUrl,
+    siteName: "CodeTutor",
+    title: "CodeTutor - Coding Interview Preparation",
+    description:
+      "Master coding interviews with curated questions, detailed explanations, and optimal solutions.",
+  },
+  twitter: {
+    card: "summary_large_image",
+    title: "CodeTutor - Coding Interview Preparation",
+    description:
+      "Master coding interviews with curated questions, detailed explanations, and optimal solutions.",
+  },
+  metadataBase: new URL(siteUrl),
 };
 
 export default function RootLayout({

frontend/src/app/patterns/[slug]/page.tsx

@@ -1,13 +1,39 @@
+import type { Metadata } from "next";
 import { getPattern, getQuestions } from "@/lib/api";
 import { QuestionCard } from "@/components/questions/question-card";
 import { Card, CardHeader, CardTitle, CardContent } from "@/components/ui/card";
 import { notFound } from "next/navigation";
 
-export default async function PatternDetailPage({
+interface PageProps {
-  params,
-}: {
   params: Promise<{ slug: string }>;
-}) {
+}
+
+export async function generateMetadata({ params }: PageProps): Promise<Metadata> {
+  const { slug } = await params;
+
+  try {
+    const pattern = await getPattern(slug);
+    const description =
+      pattern.description ||
+      `Learn the ${pattern.name} pattern with ${pattern.question_count} practice problems.`;
+
+    return {
+      title: `${pattern.name} Pattern`,
+      description,
+      openGraph: {
+        title: `${pattern.name} Pattern | CodeTutor`,
+        description,
+        type: "article",
+      },
+    };
+  } catch {
+    return {
+      title: "Pattern Not Found",
+    };
+  }
+}
+
+export default async function PatternDetailPage({ params }: PageProps) {
   const { slug } = await params;
 
   let pattern;

frontend/src/app/questions/[slug]/page.tsx

@@ -1,13 +1,40 @@
+import type { Metadata } from "next";
 import { getQuestion } from "@/lib/api";
 import { QuestionDetail } from "@/components/questions/question-detail";
 import { ProblemWorkspace } from "@/components/editor";
 import { notFound } from "next/navigation";
 
-export default async function QuestionDetailPage({
+interface PageProps {
-  params,
-}: {
   params: Promise<{ slug: string }>;
-}) {
+}
+
+export async function generateMetadata({ params }: PageProps): Promise<Metadata> {
+  const { slug } = await params;
+
+  try {
+    const question = await getQuestion(slug);
+    const description = question.description
+      .replace(/[#*`]/g, "")
+      .substring(0, 160)
+      .trim();
+
+    return {
+      title: question.title,
+      description,
+      openGraph: {
+        title: `${question.title} | CodeTutor`,
+        description,
+        type: "article",
+      },
+    };
+  } catch {
+    return {
+      title: "Question Not Found",
+    };
+  }
+}
+
+export default async function QuestionDetailPage({ params }: PageProps) {
   const { slug } = await params;
 
   let question;

frontend/src/app/robots.ts

@@ -0,0 +1,14 @@
+import { MetadataRoute } from "next";
+
+const BASE_URL = process.env.NEXT_PUBLIC_SITE_URL || "https://codetutor.example.com";
+
+export default function robots(): MetadataRoute.Robots {
+  return {
+    rules: {
+      userAgent: "*",
+      allow: "/",
+      disallow: ["/api/"],
+    },
+    sitemap: `${BASE_URL}/sitemap.xml`,
+  };
+}

frontend/src/app/sitemap.ts

@@ -0,0 +1,65 @@
+import { MetadataRoute } from "next";
+import { getQuestions, getPatterns } from "@/lib/api";
+
+const BASE_URL = process.env.NEXT_PUBLIC_SITE_URL || "https://codetutor.example.com";
+
+export default async function sitemap(): Promise<MetadataRoute.Sitemap> {
+  const entries: MetadataRoute.Sitemap = [
+    {
+      url: BASE_URL,
+      lastModified: new Date(),
+      changeFrequency: "weekly",
+      priority: 1,
+    },
+    {
+      url: `${BASE_URL}/questions`,
+      lastModified: new Date(),
+      changeFrequency: "daily",
+      priority: 0.9,
+    },
+    {
+      url: `${BASE_URL}/categories`,
+      lastModified: new Date(),
+      changeFrequency: "weekly",
+      priority: 0.8,
+    },
+    {
+      url: `${BASE_URL}/patterns`,
+      lastModified: new Date(),
+      changeFrequency: "weekly",
+      priority: 0.8,
+    },
+  ];
+
+  try {
+    // Fetch all questions for individual pages
+    const questionsResponse = await getQuestions({ limit: 1000 });
+    for (const question of questionsResponse.items) {
+      entries.push({
+        url: `${BASE_URL}/questions/${question.slug}`,
+        lastModified: new Date(),
+        changeFrequency: "monthly",
+        priority: 0.7,
+      });
+    }
+  } catch {
+    // Continue without question pages if API fails
+  }
+
+  try {
+    // Fetch all patterns for individual pages
+    const patternsResponse = await getPatterns();
+    for (const pattern of patternsResponse.items) {
+      entries.push({
+        url: `${BASE_URL}/patterns/${pattern.slug}`,
+        lastModified: new Date(),
+        changeFrequency: "monthly",
+        priority: 0.6,
+      });
+    }
+  } catch {
+    // Continue without pattern pages if API fails
+  }
+
+  return entries;
+}