Callahan Graduated from ASU with a degree in computer science and went on to work in the private sector as a software Consultant. In his role as a consultant, he worked with many different companies to improve their Software ecosystem. He also helped build new Software for many companies.
Callahan joined the Center for Hydrologic innovation to help support the centers software projects. He is currently helping the center with its AWODSS project. The goal of which is to construct a online portal to help increase knowledge and availability of water data in Arizona.