A collection of solutions leveraging the power of ZK bounties. ZK bounties are a way of privately trading sensistive information on a public blockchain such as Bitcoin. Besides providing privacy they also ensure atomicity of the transaction so none of the involving parties can cheat. It ensures that the seller of the information cannot cheat by taking the reward without delivering the correct information. Adversely it also ensures that the buyer cannot get the information without paying and equally cannot simply waste the sellers resources by ordering say a solution to a hard problem and then simply abandoning[1].
[1] This is a fatal drawback with the old way of doing Zero Knowledge Contingent Payments (ZKCP).