  NASA's Neutron Star Interior Composition Explorer (NICER) observed X-ray
emission from the pulsar PSR J0030+0451 in 2018. Riley \textit{et al.} reported
Bayesian parameter measurements of the mass and the radius of the star using
pulse-profile modeling of the X-ray data. In this paper, we reproduce their
result using the open-source software \textit{X-PSI} and the publicly available
data. We reproduce the main result within the expected statistical error. We
note the challenges we faced in reproducing the results. We demonstrate that
not only that the analysis can be reproduced, it can also be reused in future
works by changing the prior distribution for the radius, and by changing the
sampler configuration. We find no significant change in the measurement of the
mass and radius, demonstrating that the original result is robust to these
changes. Finally, we provide a containerized working environment that
facilitates third-party reproduction of the measurements of mass and radius of
PSR J0030+0451 using the NICER observations.

High Energy Astrophysical Phenomena;Instrumentation and Methods for Astrophysics;Distributed, Parallel, and Cluster Computing