The answer here is so simple, I'm surprised no one mentioned it yet. You attract top talent (of any race, creed, gender) by providing top compensation. For example, the pool of black women who have PHDs in computer science is exceedingly small. I imagine Google has a few of them on their staff but your company doesn't have any. Why do you think that's the case?
Tools and frameworks aren't going to be effective. Have you ever seen something like a company picnic as a perk in a job advertisement? Was it effective on you? It seems like you are trying to create non-monetary incentives like this, but literally, no one cares about non-monetary incentives. If you want a diverse workforce in terms of race, gender, etc., especially if jobs like computer science that don't traditionally have many minorities, the only way is to be a large successful company who can afford to pay your employees top dollar.