Uploaded May 2025 | Updated September 2026, 3 weeks ago

---

Middleware allows you to customize the behavior of server functions created with createServerFn with things like shared validation, context, and much more. Middleware can even depend on other middleware to create a chain of operations that are executed hierarchically and in order.

More in the official docs: tanstack.com/start/latest/docs/framework/react/middleware

TanStack Router Tutorial: youtube.com/playlist?list=PLOQjd5dsGSxJilh0lBofeY8Qib98kzmF5
TanStack Start Tutorial: youtube.com/playlist?list=PLOQjd5dsGSxIEKFg4dnSQ4zQkmTktfszp

_______________________________
Support my work: github.com/sponsors/Balastrong ❤️

Hit like and subscribe for more content! :D

Beginner-Friendly Open Source Projects: github.com/DevLeonardoCommunity
Join the Discord community! Here's the invite: discord.gg/bqwyEa6We6

You can also follow me on the other platforms:
Twitter: twitter.com/Balastrong
dev.to: dev.to/balastrong
GitHub: github.com/Balastrong
Home: https://leonardomontini.dev/
TikTok: tiktok.com/@balastrong
Instagram: instagram.com/devbalastrong

_______________________________
TIMESTAMPS

00:00 Introduction
00:19 Server Middleware
01:24 Client Middleware
02:25 Passing data between multiple middlewares
03:51 Full Demo
05:05 Returning an error from a server middleware
05:45 Global Middleware
06:18 TanStack Start + Query data loading

#tanstack #react #nextjs