Authentication

A practical guide to authentication in 2026 — passkeys as the primary factor, OAuth 2.1 + OIDC for federation, sessions vs JWTs, the right stack for FastAPI / Django / Hono / Next.js, and the security mistakes I keep seeing.

An end-to-end JWT auth walkthrough for FastAPI: bcrypt password hashing, access + refresh tokens, dependency-injected current user, and how to avoid common pitfalls.