DCompTB is a network testbed facility that allows researchers to rapidly design, deploy and execute complex experimental networked systems. Experiments involving hundreds of nodes can be materialized in minutes. The compute and network platforms provided by the testbed are open source hardware, providing maximum flexibility as an experimental platform. All nodes are have remotely accessible UART consoles for low-level systems development. The testbed provides advanced network modeling and emulation capabilities, allowing researchers to deploy systems in high operational-fidelity environments.