Libertarianism it not incompatible with socialism.  It is only incompatible with coercive socialism.

One of core values of socialism is that the rich have a moral obligation to redistribute some of their wealth to the poor.  However, this redistribution doesn't have to happen by coercive means.

There are also non-coercive ways of achieving this: ostracism, shaming, persuasion, education, prizes, fame, social norms, "whuffie", etc 

The crypto economy has the potential to formalize and automate these redistribution mechanisms (see Vitalik Buterin's SocialCoin idea), making them so effective that coercive, tax-based redistribution is no longer necessary.