Weak lensing directly probes the distribution of matter in our Universe, and we can use observations of this lensing to constrain cosmological properties. Many widefield surveys, such as the Dark Energy Survey (DES), have carried out such efforts and set ever-more-precise constraints on cosmology. I will present our current efforts on using existing DECam data to construct an independent, 7000 square degrees survey of the northern sky, and extract weak lensing cosmology from it. This dataset will be highly complementary to current wide-field photometric surveys, and provide a useful playground for testing methodologies for LSST-esque data. I will describe the general procedures required to extract a weak lensing catalog from these data, how our work here will inform LSST methodologies, and finally touch on the specific cosmological and astrophysical science cases we will explore with this data.