  We present a search for sterile neutrino dark matter decay signals in the
Milky Way's dark matter halo by considering the entirety of the Swift-XRT data
archive. After filtering the raw archive, we analyze a $\sim$77 Ms data set
containing the full field of view, as well as a $\sim$41 Ms data set with
point-sources excised using the Swift-XRT Point Source catalog. We report
non-detections of emission lines across the 3--6 keV continuum in both data
sets, including at and around 3.5 keV. The point-sources excised data set is
found to have higher sensitivity to faint dark matter decay signals due to its
freedom from point-source contamination and is thus used to set constraints.
Non-detections across the total data set's continuum are used to constrain the
sterile neutrino dark matter parameter space, marginally strengthening existing
X-ray constraints. Non-detections at $\sim$3.5 keV in data subsets grouped by
angular distance from the galactic center are used to constrain the 3.5 keV
line's galactic intensity profile, providing the strongest constraints to date
across $\sim$1/4 of the galaxy.
