Tera-X has decades of experience in the design of GaAs-based pulsed circuits. We validate and optimize our designs with both circuit (SPICE) and full-wave simulations. These designs are laid out for our in-house GaAs fabrication process, but can also be modified for external foundry process. These monolithic microwave integrated circuits enable the generation of ultrafast transient waveforms with picosecond duration. As an all-electronic process, complete systems are compact, lightweight, and efficient.