Examples & Use CasesPractical integrations of UsefulKey with frameworks and auth systems.Explore end-to-end examples: Example — Next.js Example — Hono Use Case — Backend API Use Case — Authentication Systems Use Case — Service-to-Service Usage Limits per KeyEnforce and decrement per-key usage counters. Provide helpers to manage remaining uses.Use Case — Authentication SystemsCombine UsefulKey with your auth system to gate access and enrich identities.