We recently pushed a change that updates Vitepress (used for the Codex docs site) to `v1.0.0-alpha.47`. It looks like this latest version of Vitepress requires Node `v16.6.0` or greater due to use of `Array.prototype.at` in its internals (parsing filenames). See the compatibility table for this method here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/at#browser_compatibility
PatchDemo is still running Node 14. This means that all attempts to build Codex inside of a PatchDemo instance now fail with the following error:
```
build error:
TypeError: filename.split(...).at is not a function
```
There are also a lot of "unsupported engine" warnings in the console output.
### Proposed Solution
We should revert the Vitepress update in our code until we can update PatchDemo to use Node 16 LTS.