  Although OSS development is very popular, ultimately more than 80 percent of
OSS projects fail. Identifying the factors associated with OSS success can help
in devising interventions when a project takes a downturn. OSS success has been
studied from a variety of angles, more recently in empirical studies of large
numbers of diverse projects, using proxies for sustainability, e.g., internal
metrics related to productivity and external ones, related to community
popularity. The internal socio-technical structure of projects has also been
shown important, especially their dynamics. This points to another angle on
evaluating software success, from the perspective of self-sustaining and
self-governing communities.
  To uncover the dynamics of how a project at a nascent development stage
gradually evolves into a sustainable one, here we apply a socio-technical
network modeling perspective to a dataset of Apache Software Foundation
Incubator (ASFI), sustainability-labeled projects. To identify and validate the
determinants of sustainability, we undertake a mix of quantitative and
qualitative studies of ASFI projects' socio-technical network trajectories. We
develop interpretable models which can forecast a project becoming sustainable
with more than 93 percent accuracy, within 8 months of incubation start. Based
on the interpretable models we describe a strategy for real-time monitoring and
suggesting actions, which can be used by projects to correct their
sustainability trajectories.
