1. A method in a data processing system, comprising the steps of: generating a plurality of individual directed acyclic graphs, wherein each of the plurality of individual directed acyclic graphs comprise a plurality of nodes representing executable tasks and each of the plurality of individual directed acyclic graphs comprise dependencies between the plurality of nodes representing the executable tasks; merging the individual directed acyclic graphs at runtime to create a merged directed acyclic graph, wherein the merged directed acyclic graph includes at least one dependency between nodes from different individual directed acyclic graphs wherein the step of merging the individual directed acyclic graphs at runtime further comprises: comparing a node in a first one of the individual directed acyclic graphs with a node in a second one of the individual directed acyclic graphs to determine if there is a merged dependency between the compared nodes, and creating a directed arc in the merged directed acyclic graph to reflect the merged dependency, wherein the merged dependency did not exist in the first one or the second one of the individual directed acyclic graphs individually; and executing the merged directed acyclic graph while the merged directed acyclic graph is being constructed.