  This paper presents LAGOON -- an open source platform for understanding the
complex ecosystems of Open Source Software (OSS) communities. The platform
currently utilizes spatiotemporal graphs to store and investigate the artifacts
produced by these communities, and help analysts identify bad actors who might
compromise an OSS project's security. LAGOON provides ingest of artifacts from
several common sources, including source code repositories, issue trackers,
mailing lists and scraping content from project websites. Ingestion utilizes a
modular architecture, which supports incremental updates from data sources and
provides a generic identity fusion process that can recognize the same
community members across disparate accounts. A user interface is provided for
visualization and exploration of an OSS project's complete sociotechnical
graph. Scripts are provided for applying machine learning to identify patterns
within the data. While current focus is on the identification of bad actors in
the Python community, the platform's reusability makes it easily extensible
with new data and analyses, paving the way for LAGOON to become a comprehensive
means of assessing various OSS-based projects and their communities.
