Dev Guide: Secure JWT Auth Flow for React Native and FastAPI in Production

A developer has published a detailed guide covering a production-ready JWT authentication system that integrates React Native (via Expo) with a FastAPI backend. The setup issues two tokens on login — a short-lived access token and a longer-lived refresh token — both stored securely using expo-secure-store on iOS and Android devices. API requests automatically attach the access token via an Axios interceptor, while a response interceptor silently refreshes expired tokens without logging users out. A key security detail highlighted is the use of a 'type' claim to prevent refresh tokens from being replayed as access tokens, a step the author notes most tutorials omit. The guide uses PyJWT and bcrypt directly, deliberately avoiding the passlib library due to ongoing maintenance concerns.