Manu Cornet worked at Google for 14 years and recently moved to Twitter (he’s since been caught up in the great Twitter purge) and has an interesting discussion of the differences in the companies’ cultures as seen from a staff engineer’s perspective.
The differences aren’t particularly profound and probably reflect Google’s larger size and older age. I’m not sure Cornet would agree but to me it seems as if Twitter is less bureaucratic. Again, that probably reflects smaller size and younger age.
His discussion covers such things as outsourcing, use of open source software, remote friendliness, gender diversity, managerial technical ability, documentation, code ownership, code reviews, and a few other items.
My career was spent mostly with comparatively smaller companies so I always find these sorts of discussion interesting: a peek into another dimension. If you’re interested in different work cultures, Cornet’s discussion is a worthwhile read. It’s not too long so it’s easy to find time for it.