I'm thinking of promoting ELL to Japanese programmers who use the programming language Ruby.
If I wanted to promote a Stack Exchange site to Australian programmers, I'd say "[IT security Stack Exchange] is like Stack Overflow, but for [security issues]". But I don't know whether if I did that with Japanese programmers, I'd get a response of "What's Stack Overflow"?
I'm pretty sure that native speakers of Japanese who are living in Japan aren't very active on Stack Overflow, and possibly don't even have accounts. However, I don't know whether that means they don't use it at all, or that they're "read only" users.