The evaluation of new network protocols, applications, and architectures, requires the use of many kinds of experimentation environments: simulators, emulators, testbeds, and sometimes, combinations of these. As the functionality and complexity of these tools increases, mastering and efficiently using each of them is becoming increasingly difficult. In this paper, we consider how to make it easier to use multiple tools separately and together to improve the productivity of network researchers. We show how a single object model which encompasses every aspect of a typical experimentation workflow can be used to completely describe experiments to be run within very different experimentation environments. Although Nepi is still in early prototyping stage, we expect that its ability to describe and automate easily complex mixed experiments will enable further experimentation with heterogenous networks.