A walkthrough of building an open-source SaaS landing page template using Next.js 16, React 19, shadcn/ui with the new base-nova style, Tailwind CSS v4, and TypeScript. Covers eight practical lessons learned during the build: shadcn/ui's shift from Radix to Base UI primitives (where ARIA state replaces parallel JS state), Tailwind v4's CSS-first theme configuration via @theme inline, OKLCH colors for predictable dark mode contrast, flat page architecture for easy customization, staggered animations with motion/react's staggerChildren, CSS-only infinite marquee without third-party packages, CSS subgrid for cross-card row alignment in pricing layouts, and inline SVG paths for brand logos. Also includes three retrospective improvements the author would make if starting over.
