On SO, maybe in chat. Otherwise, OP needs to find a place to ask, maybe softwarereqs (but it would have to be changed quite a bit to be on topic there too, and wouldn't really resemble this question) or a forum for tutorials. — CollinD22 secs ago
This week there don't seem to be quite as many suitable candidate questions, but still far enough for the QotW to make sense. I use this search query to home in on possible candidates, maybe you'll find some nice questions as well.
@TinyGiant I can't see that “nice conceptual answer”. All answers fundamentally list one or more technology suggestions. If the question was stripped from all recommendations, it would still be far too broad for either SO or Software Engineering.
The question boils down to “How can I implement a search/show-context/expand-on-demand interactive graph visualization for 3M nodes?”, the request for tech recommendations is just incidental. But it's really not a question that fits well into the Q&A model.
It's time to choose a Question of the Week! The Question of the Week demonstrates what a good on-topic question looks like. Last week, we picked:
What is the importance of the vision document and how it helps development? by user1620696
Suggest the next Question of the Week by answering here wi...
If you don't want programmers to be able to change a variable, then mark it const. I don't really understand your question though. — Rakete111150 secs ago