Developing power and thermal models in Python to support hardware development.

I was personally in charge of location services at ZipRecruiter for over seven years, designing several generations of geolocation microservices, writing all code and documentation, and supporting all users.Designed, wrote, and maintained a location resolver REST microservice called "locres". Using Python and a database file, locres parses location strings and returns information about the location. It also has "reverse lookup" and other features.Designed, wrote, and supported a geographic location autocomplete REST microservice called "geoac". Using Python and a database file, returns a list of possible completions to a string, sorted so the most likely result is at the top of the list.These two services serve up hundreds of millions of requests per week. They run in Docker under Kubernetes on Amazon Web Services (AWS) cloud infrastructure.Wrote a thorough unit test suite for both microservices using pytest, with hundreds of test cases to assure quality and prevent regressions.Wrote a PySpark application to clean and organize gigabytes of location data and write the database files for the two services, and to publish location data tables to the datalake.Contributed a great deal of Python code to the common code libraries, including a microservice framework implemented on top of Flask and some custom wrappers around LMDB (the Symas Lightning Memory-mapped Database) for Python use.

Developed and maintained Python code used for REST web services in Disney's IT department, working out of Disney's offices in Seattle.

Hired to assist James D. "JJ" Johnston in audio R&D. Designed and wrote a DSP engine in C, improving upon similar work I did for JJ while he was at Microsoft. The engine had a custom scripting language to configure it and JJ was able to rapidly try new ideas using it. We developed audio processing prototypes that ran at production speed.I built a complete unit test suite using Python and pytest, and heavily tested with Valgrind to make sure that there were zero memory leaks. I built and tested on Linux, Mac OS X, and Linux.DTS got two US patents from this work: 8908874, 9728181I ported the DSP engine to both TI and Analog Devices DSP chip architectures and worked on some hardware prototypes using it.I did all the embedded software development work on the "FuzeBox", a demo platform that could be controlled with an iPad or Android tablet over WiFi. I designed a JSON control protocol, and wrote a serial port ISR and a JSON parsing library for the DSP chip.Also, I designed and wrote a Digital Rights Management system called "DSEC", which used OpenSSL to generate license files; and a C library that used libtomcrypt to check the signature on the license files and decide if the software using DSEC should run.Also, I worked on Android app development for a few months, including some automated app testing.

Developed embedded Python for a consumer electronics video player device code-named "Facet" that was planned to be released under the name "RealDVD". This would have been an Internet-connected streaming video player that also had a feature of playing back the consumer's own DVDs, live or from a hard drive.Wrote metadata handling code using Python, SQLite, and a Python ORM library called Autumn. Added multithreaded support to Autumn. With permission from RealNetworks, I contributed my changes to the Autumn ORM library.Designed and wrote a REST web service for identifying DVDs and serving up metadata about them, using Python and Django. This downloaded data from Gracenote, cleaned and organized it, and served it up. Also added debugging/monitoring code.RealNetworks included an idea from the above work in a US patent: 9536557I built the development servers, installing CentOS, MySQL, Django, and Memcached; and supervised the deployment of the production servers. The short-lived "RealDVD for Windows" software program used the REST service in production.

Designed and built a DSP engine and research tools in C to support research by James D. "JJ" Johnston in the Core Media Product Team. I was hired to help code up a few prototypes but instead I made a custom, scriptable tool for general audio processing.Once I had the DSP engine working, I spent the rest of the time adding features as requested by JJ Johnston. We were able to expand the scope of work beyond what was originally planned.