Add docs for leveraging outputStandalone config

docs/advanced-features/output-file-tracing.md

@@ -18,7 +18,26 @@ Next.js' production server is also traced for its needed files and output at `.n
 
 To leverage the `.nft.json` files emitted to the `.next` output directory, you can read the list of files in each trace which are relative to the `.nft.json` file and then copy them to your deployment location.
 
+## Automatically Copying Traced Files (experimental)
+
+Next.js can automatically create a `standalone` folder which copies only the necessary files for a production deployment including select files in `node_modules`.
+
+To leverage this automatic copying you can enable it in your `next.config.js`:
+
+```js
+module.exports = {
+  experimental: {
+    outputStandalone: true,
+  },
+}
+```
+
+This will create a folder at `.next/standalone` which can then be deployed on it's own without installing `node_modules`.
+
+To make leveraging this output easier a minimal `server.js` file is also output which can be used instead of `next start`. This minimal serer does not handle serving the `static` directory as this should be handled by a CDN instead.
+
 ## Caveats
 
+- While tracing in monorepo setups, the project directory is used for tracing by default. For `next build packages/web-app`, `packages/web-app` would be the tracing root and any files outside of that folder will not be included. To include files outside of this folder you can set `experimental.outputFileTracingRoot` in your `next.config.js`.
 - There are some cases that Next.js might fail to include required files, or might incorrectly include unused files. In those cases, you can export page configs props `unstable_includeFiles` and `unstable_excludeFiles` respectively. Each prop accepts an array of [globs](<https://en.wikipedia.org/wiki/Glob_(programming)>) relative to the project's root to either include or exclude in the trace.
 - Currently, Next.js does not do anything with the emitted `.nft.json` files. The files must be read by your deployment platform, for example [Vercel](https://vercel.com), to create a minimal deployment. In a future release, a new command is planned to utilize these `.nft.json` files.