Explains OAuth 2.0 (delegated authorization) and OpenID Connect (authentication/identity) as standards for secure third-party access in SPAs and microservices; details flows and tokens (access/refresh vs ID), contrasts purposes, shares best practices (choose flow, validate and securely store tokens, handle revocation), illustrates with a FitBuddy–Spotify integration, and advises combining both for a robust, seamless user experience.
Guide for full stack devs to master client-side routing in React SPAs with React Router: why it matters (speed, UX, performance), core features (declarative routes, history, rendering), setup example, and best practices (params, nested routes, redirects, SSR, code splitting). Includes a fitness app use case and tips for scaling, state integration, and SEO.
