What would you have done differently in retrospect?

What I would tell my younger self:

Only listen to your users and customers, ignore everyone else.

Don't hire an external CEO unless you're ready to leave. Hiring a CEO will not fix the loneliness of not having a co-founder.

Having haters is part of success. Accept it, and try to not let it get to you.

Don't partner with Red Hat. They are competitors even though they're not honest about it.

Not everyone hates you even though it may seem that way on hacker news and twitter. People actually appreciate your work and it will get better. Keep going.