Authentication Strategies in NestJS with JWT

Stateless authentication lets your API verify users without server-side sessions. JWT is the standard way to do it.

How JWT works

A token carries a signed payload — user id, roles, expiry. Your server verifies the signature on each request, so no session store is needed.

Implementing login and validation

Issue a token when credentials check out, and validate tokens on protected routes with a Passport strategy backed by an AuthGuard.

Keeping it secure

Sign tokens with a strong, secret-held key, set sensible expiry, and protect refresh flows. Never trust unsigned or expired tokens.

Wrapping up

JWT + guards gives you clean, stateless security that integrates naturally into NestJS's architecture.