Wrangler now uploads source maps by default

Cloudflare announced on 20 October that wrangler deploy, wrangler versions upload and wrangler preview now generate and upload source maps by default, from Wrangler 4.150.0 onwards. Until now you had to set upload_source_maps in your config to get original file names and line numbers in a stack trace rather than minified output.

The same applies to cf deploy when used with the Cloudflare Vite plugin 1.64.0 or later. Remapped traces show up in Workers Logs, real-time logs, Tail Workers and Workers Issues. Cloudflare says source maps are applied after a Worker runs, so they add nothing to CPU time, bundle size or cold starts. Custom builds get the same treatment automatically, though unresolvable maps, such as inline data: source maps, are skipped rather than failing the deploy.

# opt out if you need to
upload_source_maps = false

Why it matters: debugging a production Worker from a minified stack trace is one of the more annoying parts of the platform, and until now it needed an extra config line most people never add. Making it the default means a crash in a live Worker is readable without having gone looking for this setting first.