His particular expertise is UNIX programming, databases, server-side programming and scripting, which he has applied to the creation of a number of projects in both the commercial and art domains. Feinberg directed the back-end programming of Martin Wattenberg & Marek Walczak's "Apartment" project, which has been shown at the Whitney Museum and the Ars Electronica Center, Austria. He has also developed client-side and server-side utilities for commercial organizations including Smartmoney.com and Linkbank.