As the sole software and electrical engineer at the company, I built many critical components that enable our DNA sequencer to automatically collect data:

* I rewrote drivers for our existing hardware from scratch in C++ (17) and Python with NumPy and PySide (Qt), which include high-power LEDs for TIRF microscopy and PID temperature control.

* I implemented support for a wide range of camera sensors, including both purpose-built microscope cameras and inexpensive bare sensors like the Raspberry Pi HQ camera. To synchronize the latter with the TIRF flashes, I heavily optimized the imaging pipeline and built the ability to arbitrarily start and stop camera exposures at any time. This required reverse engineering the behavior of the sensors’ undocumented vertical sync pins and digging deep into libcamera and V4L2 in the Linux kernel.

* I added support for automatic focus control and lens filter selection, including a custom motor driver circuit and the corresponding control software.

* I assembled and reworked PCBs as needed to build and maintain our sequencing instruments.

I also contributed beyond the data collection instrument:

* I implemented analysis tools in Python, including a method for deduplicating data points and a color transformation that mitigates crosstalk between wavelengths.

* I overhauled our website as we released the hardware models, driver software, and analysis tools as open source.

Throughout this, I worked directly with our stakeholders -- leadership and biochemical engineers -- to gather and refine requirements.

While on the hardware test team, I developed efficient, automated solutions to ensure that MEMS ultrasound transducers, PCBs, and assembled probes were fully functional prior to delivery to customers:

* I was primarily responsible for the design and implementation of the test software, which is mostly written in Python with NumPy and PyQt and C++ (17).

* I maintained the Linux systems it ran on using Ansible and helped design the associated test boards and hardware fixtures.

* I frequently worked cross-functionally with hardware teams, including electrical, mechanical, FPGA, and semiconductor engineers, towards these and other goals.

* I deployed and maintained these solutions, sometimes going abroad to visit our contract manufacturers onsite.

In between hardware releases, I contributed to other parts of the company:

* iOS DevOps: I added automatic end-to-end testing of imaging, probe configuration, and firmware upgrades to the Buildkite CI/CD pipeline. To do this, I designed and deployed a custom test harness that integrates iPhones and ultrasound probes, including the iOS build target, example tests, control API, and hardware fixtures, to our on-premises fleet of physical Macs.

* Firmware: I greatly improved our production yield by implementing on-probe calibration storage, which allowed us to correct CMOS and transducer imperfections in software.

* Analytics: I enabled FDA compliance over time by implementing continuous monitoring of probe health with logging in firmware and the iOS and Android apps, which includes generalized device usage, battery statistics, and self-diagnostic tests.

* Linux DevOps: I improved the security and ease of deployment of our test software by writing a tool to package it as a compiled binary containing its wide-ranging dependencies in the AppImage format. Because we used this deployment method at a new CM, our source code was not exposed when their network was compromised.

While working on the Microsoft Word and Mail for Windows 10 teams, I focused on improving email reading and authoring, especially around accessibility, HTML rendering fidelity, and automated integration testing.

During my internship, I extended APIs to an internal version control system, providing a unified way to view and manage changelists. These APIs are used to test and search Google’s codebase.