I've made substantial contributions to a number of open source projects in several areas. The projects below are some of the more important contributions.
OpenPLC Project is a complete solution for programming programable logic controllers (PLCs) using IEC 61131-3 languages (such as structured text and ladder diagrams).
I am presently active in the project working on code runtime improvements and automated testing. You can usually find me on the Gitter channel.
openfmb-device-simulator is a simple application to bootstrap development of OpenFMB messaging capabilities with NATS. It creates several simple devices that publish and subscribe to NATS channels using the OpenFMB information model and is the fastest way to get started with OpenFMB.
pcb-tools is Python library for parsing and manipulating Gerber (RS-274) and Excellon files that are the defacto standard used for printed circuit board (PCB) manufacturing. I contributed support for aperture macros, drill files, and countless bug fixes.