  Game theory is often used as a tool to analyze decentralized systems and
their properties, in particular, blockchains. In this note, we take the
opposite view. We argue that blockchains can and should be used to implement
economic mechanisms because they can help to overcome problems that occur if
trust in the mechanism designer cannot be assumed. Mechanism design deals with
the allocation of resources to agents, often by extracting private information
from them. Some mechanisms are immune to early information disclosure, while
others may heavily depend on it. Some mechanisms have to randomize to achieve
fairness and efficiency. Both issues, information disclosure, and randomness
require trust in the mechanism designer. If there is no trust, mechanisms can
be manipulated. We claim that mechanisms that use randomness or sequential
information disclosure are much harder, if not impossible, to audit. Therefore,
centralized implementation is often not a good solution. We consider some of
the most frequently used mechanisms in practice and identify circumstances
under which manipulation is possible. We propose a decentralized implementation
of such mechanisms, that can be, in practical terms, realized by blockchain
technology. Moreover, we argue in which environments a decentralized
implementation of a mechanism brings a significant advantage.
