What's the libertarian / ancap solution to scammers?

Yelling and pointing them out is only partially effective because it's not possible to warn (or even convince) the whole world.

Ostracizing has the same issue - there are always more fools in the sea for scammers to harvest.

Civil lawsuits are similarly flawed because the successful scammer will be better funded than the victims.

Seems like an opportunity for a̶s̶s̶a̶s̶s̶i̶n̶a̶t̶i̶o̶n̶ prediction markets...