Meetups have their membership figures, and one way to communicate to a Meetup's members is to arrange for an email to be sponsored. The meetup can have details of the Job and Employer and any requirements for applicants.
Example of an Email but can be customized
A meetup member who came to our meetup has a job available.
"We are from retail fashion and looking for a sales assistant. Any nationality is welcome but have to speak Japanese well. We are a large organisation so if they want to pursue their career in fashion or retail, great opportunity."
Please let me know if you are interested, and I can put you in touch with the member. It was great to meet him and talk about his company's culture.