How I wire Mux video into a Next.js + Sanity CMS upload workflow

Adding Mux video to a Sanity + Next.js project sounds straightforward until you hit the sharp edges: the Sanity Mux plugin needs a server-side proxy to keep your token secret, signed playback URLs require a short-lived JWT on every render, and the poster frame you pull from Mux directly affects LCP. Here is the exact setup I use in production.

Installing the Sanity Mux plugin

Start in your Sanity Studio project:

npm install sanity-plugin-mux-input

Enter fullscreen mode