That's awesome. If a PR was opened that added autocomplete and/or finding callers and/or refactoring (and assuming that the code is good), would you guys be open to merging it? Or would it be delayed so that the core functionality can be focused on?
We currently store method/function callers in the sqlite database (see https://github.com/etsy/phan/blob/master/src/Phan/Analyze/Br...), but aren't yet exposing an interface for getting callers. We'll want to store callers for constants, classes, properties and global variables as well.