I like the idea - but you need hiring managers to post jobs before it will be worthwhile. What is in it for them? Because it sounds to me like a way to voluntary have talent filter my jobs out of their search.
I honestly think a lot of hiring managers don’t know what is the best way to hire. So many things in life are based on copycat culture (every NBA team shoots 3s now like the Warriors all of a sudden for example), and every software company now needs to make sure all their candidates know how to write optimal algorithms like Facebook/google candidates. But a lot of these companies are not google or Facebook or amazon, so they rely on stuff like Codality to essentially copy the hiring process of a top company when they really don’t even solve the kinds of problems google engineers deal with.
Basically need a Codality for normal companies with reasonable mixture of real world practical problems, and reasonable algorithm questions. Then hopefully the copy cat culture can pick up on that and we’ll have an organic fix to the shitty programming interview puzzle garbage filtering out decent developers who are just fine for most companies.
I agree on your first point - it's like building a social network and having no users (chicken and the egg problem). There's a lot in it for the company / hiring manager, I think I've answered this question in the FAQs on the site but long story short: companies will also benefit from having candidates doing an interview that they feel shows their full potential.
Basically need a Codality for normal companies with reasonable mixture of real world practical problems, and reasonable algorithm questions. Then hopefully the copy cat culture can pick up on that and we’ll have an organic fix to the shitty programming interview puzzle garbage filtering out decent developers who are just fine for most companies.