Hackathons are short design events at which participants collaboratively progress through the entire design process. They pose opportunities for design research, but the existing research is limited, as is the understanding of design activity at hackathons. In our study, we summarize the hackathon design process of 10 interview participants from varying disciplines, levels of experience, and hackathon events. The summarized account reveals a decreased emphasis on the beginning phases of the design process, mainly problem definition, but an increased emphasis on the end, specifically the pitch portion of the event. These differences are mainly due to the limited time frame. We further assess the effect of time limitations at hackathons by comparing hackathons to other instances of design, emphasizing the impact of time constraints on iteration. We conclude our discussion with an exploration of the role expertise has on the design process by comparing the accounts of designers and developers.