  This paper presents the latest improvements introduced in Version 4 of the
UQpy, Uncertainty Quantification with Python, library. In the latest version,
the code was restructured to conform with the latest Python coding conventions,
refactored to simplify previous tightly coupled features, and improve its
extensibility and modularity. To improve the robustness of UQpy, software
engineering best practices were adopted. A new software development workflow
significantly improved collaboration between team members, and continous
integration and automated testing ensured the robustness and reliability of
software performance. Continuous deployment of UQpy allowed its automated
packaging and distribution in system agnostic format via multiple channels,
while a Docker image enables the use of the toolbox regardless of operating
system limitations.
