Parsing is definitely a big part of it, and it's a fair point that for search-based Code Navigation, we don't have to do any real heavy lifting on the analysis side. That said, I think the article describes our non-functional requirements well (zero-config, incremental, language-agnostic). It's those non-functional requirements which are most important for the “at scale” part. I'd go so far as to suggest that any static analysis implementation that can't meet those requirements would be nigh impossible for us to roll out across the entire GitHub corpus.