NSL recognizes the need within high energy science and inertial fusion to develop ultrafast diagnostics to assess plasma conditions for High Energy Density science and Inertial Fusion experiments. The current limitation of existing measurement tools is in the constraints of streak cameras. Therefore, there is interest in developing ultrafast pixel cameras by reading high speed photodetectors and sensor arrays with compact electronics. Such an approach would facilitate transformative diagnostics at many DOE labs. This new measurement approach is made possible by integrating advances in 1) High-speed multi-channel waveform digitizing chips, 2) ultra-fast photodiode x-ray and particle detector arrays, and 3) advanced packaging and interconnect technologies. The proposed approach allows arrays from 10k of pixels of time-resolving detectors to be easily and cost-effectively integrated into HED experiments, something presently out of reach of the majority of scientists at mid-scale HED facilities and for individual-investigator research projects. The sensor array will be assembled on a separate and removable electronics board to enable customization for specific measurements optimized for x-rays, neutrons, visible light, electrons, or ions. Given recent advances in detectors and electronics, there is a chance to make a 10-20x improvement in performance while lowering the cost. The main goal of this Phase I project is to demonstrate the feasibility of the WURP and de-risk a Phase II project to actually develop a working prototype. In order to achieve this, the main objectives consist in: Understand signal levels and performance of the proposed APDs Understand and design for interfacing requirements between APDs and existing Nalu readout chips.Design and develop a preliminary prototype system, package it and perform laser or other testing. Compare test results with simulations and other calculations for timing and spatial resolution. NSL proposes to design and commercialize the Wideband Ultrafast Recorder for high energy density Plasmas. The WURP as a commercially available camera with common knowledge base, hardware, firmware, and software can be deployed in a variety of experiments and applications from massive projects such as those at the National Ignition Facility, subcritical experiments at the Nevada National Security Site, or Laser Energetics experiments.