If you are libertarian, you have to be a prison abolitionist. The prison system is modern day slavery, the antithesis of liberty. 1 out of every 110 adults in America is incarcerated. Many of them are enslaved for having committed non-violent and victimless "crimes."
If we free all those people, there won't be enough jobs for them. This means that when we free them they must either be employed by the State or provided with a basic income in order to survive. And if you are libertarian, it is clear that basic income is the most libertarian of the two options. But it would be preposterous to give a basic income just to ex-convicts, giving them an advantage over everyone else. No, we must go for a universal basic income, providing everyone with the minimum necessary for survival.
This wouldn't just liberate prisoners and eliminate modern slavery. It would liberate all people from wage-slavery. It's impossible to be libertarian without advocating universal basic income. If you're not a UBI supporter, you're not libertarian. The hierarchy and domination of workers by bosses, as well as domination of tenants by landlords, within our society is fundamentally non-libertarian. This anti-libertarian aspect of capitalism can easily be eliminated by a universal basic income in conjunction with land value tax. Land value tax and universal basic income in the form of a citizen's dividend as a share of ground-rent is the bedrock, the foundation, of true libertarianism.
But liberty also requires access to affordable and reliable healthcare to the greatest extent feasible. If you can easily be enslaved by debt because of medical bills, then you are not actually free. Certain welfare measures, like single-payer healthcare and universal basic income, lay the foundation for a truly libertarian society. This is what I call libertarian social democracy—social democracy reoriented towards human liberation.