Next.js

Getting Started

1. What is Next.js?Why React alone isn't enough for most apps, and what a meta-framework like Next.js adds on top of it.
2. Creating a Next.js ProjectScaffolding a new app with create-next-app and a first look at what it generates.
3. The App Router File SystemHow folders and special files inside app/ turn into real URLs, with no router configuration to write.

Routing & Layouts

1. Nested LayoutsHow layouts stack inside each other by folder depth, and why that keeps state alive across navigations.
2. Dynamic RoutesGenerating routes from data with bracketed folder names, and why params arrives as a Promise.
3. Route Groups and Project OrganizationUsing (parentheses) and _underscore folders to organize routes and colocate files without changing any URLs.
4. Linking and NavigationWhy next/link isn't just a styled anchor tag, and when to reach for the useRouter hook instead.

Server & Client Components

1. Server vs. Client ComponentsThe mental model behind React Server Components — why every component is server-only until you say otherwise.
2. Using "use client" EffectivelyWhere to place the use client boundary so you don't accidentally turn your whole app into a client bundle.
3. Composing Server and Client ComponentsPassing data across the server/client boundary safely, and the patterns that keep the split from becoming awkward.

Data Fetching & Mutations

1. Data Fetching in Server ComponentsFetching with async/await directly in components, and the difference between sequential and parallel requests.
2. Caching and RevalidationWhy fetch isn't cached by default, and the three ways to control how long data sticks around.
3. Server ActionsRunning server-side mutations directly from a component with the use server directive, no separate API route required.
4. Forms with Server ActionsShowing pending state and validation errors for a Server Action using React's useActionState hook.

Rendering & Performance

1. Static and Dynamic RenderingHow Next.js decides whether a route is prerendered once or rendered fresh on every request.
2. generateStaticParams and Incremental Static RegenerationPre-rendering specific dynamic routes at build time, and refreshing them later without a full redeploy.
3. Loading States and StreamingUsing loading.tsx and Suspense to show something useful while slow data is still on its way.

Error Handling & SEO

1. Error HandlingCatching render-time crashes with error.tsx, and showing custom 404s with not-found.tsx and notFound().
2. The Metadata APISetting page titles, descriptions, and social preview data with the static metadata export and generateMetadata.
3. Image Optimization with next/imageWhy a plain img tag is a performance trap at scale, and what the Image component does about it automatically.

Backend Features

1. Route HandlersBuilding actual API endpoints inside the App Router with route.ts and the Web Request/Response APIs.
2. Proxy (formerly Middleware)Running code before a request completes to redirect, rewrite, or inspect it — and why it's now called Proxy.
3. Environment VariablesKeeping secrets out of your bundle while still making the values you actually need available in the browser.

Shipping to Production

1. Deployment and Best PracticesShipping a Next.js app to production, and the habits worth carrying forward from this course.