1. A method for moving a message transform from a source broker to a target broker in a distributed messaging system, wherein the distributed messaging system includes a network of broker machines, wherein a plurality of message transforms are deployed in the network of broker machines, and wherein the plurality of message transforms take as input one or more sequences of messages and produce as output one or more sequences of messages, the method comprising: starting on the target broker a copy of a given message transform from the source broker; duplicating all inputs into the given message transform on the source broker to additionally go to the copy of the given message transform on the target broker; and duplicating all outputs of the given message transform on the source broker to also go from the copy of the given message transform on the target broker to appropriate children nodes within the distributed messaging system.