Meetup users are usually well connected professionals who have a strong interest in the topic of the groups and events at hand. This makes it a great place to find enthusiasts in the domain you are sourcing for.
Meetup is a platform where groups around a certain topic get together and organize events. These interests can be both nonprofessional and professional. There are profiles of individual members but they are usually not very rich in information. The value sits in the groups that an individual user is a member of. Based on those groups (and events) you can learn about their interests and skills.
Basically two things are important in Meetup as source for talent: the groups (including the events) and the profiles.
A: Group title
B: Group location, amount of members and organizers
C: Group description
D: Upcoming and past events within the group
E: Group members
F: Location of individual member
G: Introduction section of member, usually not filled in
H: Other groups the user is a member of
I: Interests based on pre-configured tags
One of the most effective ways of finding talent is to attend the relevant Meetups that you can find. Because profile information is scarce, you would have to cross reference data if you find interesting profiles to enrich the information you can find about the candidate.
You can search Google for Meetup groups that are relevant to your sourcing goals.
Search relevant Meetup groups in Meetup directly.
Recruiting is competitive, if you know how to find talent that is less competed for, you win.
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