This is really interesting and I hope it does well! Are you considering refining the domains at all, like say splitting development and technology into machine learning, devops, webdev, etc?
What are my future plans in this regard though? When the site gets past 1K users, I will start brainstorming and developing a new way for users to select their categories. Likely through a textbox vs multiple checkboxes, where people could type the areas they are into and they would autocomplete. I'd like to also let users suggest categories, eventually maybe even let them create their own interests. Could be exciting!