Make a good website; try to get graphic and Ux designers on board so it won’t be fugly; then contact people, one at a time, using personalized emails. They’ll agree to be on there. Eventually you’ll hit enough of a critical mass that people will start signing themselves up somehow, or asking to be on there. How do you verify? How do you keep spam out? You can figure that out next year or the year after.

Then figure out why a person might want to visit your site. Curiosity? Interest in a person? To learn if a foss project is any good? To see who has traction to decide what to contribute to? Something else?

Bonus points: a podcast with interviews with various community leaders; or try to encourage a volunteer to do such a thing. And try to get on other pro open source podcasts. I bet companies like purism would love any free publicity they can get

Then, I’d you catch on, years from now, look out for Microsoft trying to crush you via some competing index tied to GitHub. Try to avoid the temptation to be acquired by Microsoft. Try to set up your company in a way that convinces foss people that this can never happen, Eg, put some fsf people on the board or something?

Lastly, to make the gnu people happy, make your website usable without proprietary JavaScript and consider open sourcing your client and server code. After all, the valuable thing you hold isn’t the site or tech: it’s the network and traction you build