I use a combination of tag search, ack, and glean (https://github.com/silentbicycle/glean https://github.com/silentbicycle/glean), a search tool I've been worki

I use a combination of tag search, ack, and glean (https://github.com/silentbicycle/glean https://github.com/silentbicycle/glean), a search tool I've been working on. All three have good Emacs integration.