- Updating the herald rule on server side and the lint on client side is painful
- In theory lint should work reliably and wouldn't have to care about Herald then
- Using grep for linters isn't ideal, because it triggers some false positives
TL;DR: Add a custom field in differential where you run custom rules. It will trigger a bunch of custom PHP code that Dropbox @devd would attach to Phabricator to block reviews. The custom field will get to emit HTML that can be embedded into the diff (like failing the page, emailing someone, show warnings).