Computational research and data analytics increasingly relies on complex
ecosystems of open source software (OSS) "libraries" -- curated collections of
reusable code that programmers import to perform a specific task. Software
documentation for these libraries is crucial in helping programmers/analysts
know what libraries are available and how to use them. Yet documentation for
open source software libraries is widely considered low-quality. This article
is a collaboration between CSCW researchers and contributors to data analytics
OSS libraries, based on ethnographic fieldwork and qualitative interviews. We
examine several issues around the formats, practices, and challenges around
documentation in these largely volunteer-based projects. There are many
different kinds and formats of documentation that exist around such libraries,
which play a variety of educational, promotional, and organizational roles. The
work behind documentation is similarly multifaceted, including writing,
reviewing, maintaining, and organizing documentation. Different aspects of
documentation work require contributors to have different sets of skills and
overcome various social and technical barriers. Finally, most of our
interviewees do not report high levels of intrinsic enjoyment for doing
documentation work (compared to writing code). Their motivation is affected by
personal and project-specific factors, such as the perceived level of credit
for doing documentation work versus more "technical" tasks like adding new
features or fixing bugs. In studying documentation work for data analytics OSS
libraries, we gain a new window into the changing practices of data-intensive
research, as well as help practitioners better understand how to support this
often invisible and infrastructural work in their projects