Protected Source Maps: Ship browser source maps securely
By Steven Van ·
Protected Source Maps gates production .map files behind Vercel Authentication on all plans, with no redeploy needed to enable it.
Production source maps on Vercel can now be restricted to authorized viewers with Protected Source Maps. When enabled, a deployment serves its .map files only to users who can already access it, such as team members with at least viewer access; everyone else gets a 404 instead of the file.
Source maps give readable stack traces and original file names and line numbers for minified production code, so restricting them lets a team and its error trackers debug without publishing source code to anyone who requests it. New projects have Protected Source Maps enabled by default; existing projects can turn it on from Settings → Deployment Protection, with no redeploy needed. The Vercel Toolbar can be used to view protected source maps in the browser.