Open-source projects do not exist in a vacuum.
% Besides being developed by the project community,
They benefit from reusing other projects and themselves
are being reused by others, creating complex networks of
interdependencies, i.e., software ecosystems.
Therefore, the sustainability of projects comprising
ecosystems may no longer by determined solely by factors
internal to the project, but rather by the ecosystem context
as well.

In this paper we report on a mixed-methods study of
ecosystem-level factors affecting the sustainability of
open-source Python projects.
Quantitatively, using historical data from 46,547 projects in
the PyPI ecosystem, we modeled the chances of project development
entering a period of dormancy (limited activity) as a function
of the projects' position in their dependency networks, organizational
support, and other factors.
Qualitatively, we triangulated the revealed effects and
further expanded on our models through interviews with
project maintainers.
Results show that the number of project ties and the
relative position in the dependency network have
significant impact on sustained project activity, with
nuanced effects early in a project's life cycle and later on.