How to add API key authentication to a Next.js SaaS -- generating keys with crypto.randomBytes, storing only the SHA-256 hash in Drizzle ORM, and validating them in route handlers without ever persisting the plaintext secret.
How to validate all environment variables at startup using Zod in a Next.js App Router SaaS -- a pattern that makes missing secrets fail immediately with a clear error instead of crashing mid-request.
How to add full-text search to a Next.js SaaS using PostgreSQL tsvector, Drizzle ORM sql templates, a GIN expression index, and a URL-driven server component that composes cleanly with pagination.
How to query aggregated data with Drizzle ORM, fetch it in a Next.js server component, and render it with a Recharts area chart that respects dark mode -- the full pattern for a SaaS dashboard.
How to build reusable offset pagination in a Next.js App Router SaaS -- parallel count and rows queries in Drizzle ORM, URL-driven page state in server components, and a shadcn Pagination component wired to search params.
How to wire up Claude API tool use in a Next.js App Router SaaS -- defining tools, running the agentic loop until stop_reason is not tool_use, and keeping the route thin while business logic stays in the service layer.