The cosmic microwave background (CMB) provides a powerful tool for study of the history and evolution of the universe. Several decades of CMB measurements have yielded an increasingly clearer picture of the contents, structure, history, and fate of the cosmos. While some information channels in the CMB have been measured to their fundamental sensitivity limit, a host of physics remains to be extracted from the faint polarization anisotropies and small-scale angular correlations of the CMB. To such an end, a vibrant field of complementary measurements has developed over time. Adding to these is the Simons Array, a new ground-based telescope array in the Chilean Atacama desert designed to simultaneously search for signatures of cosmic inflation and precisely characterize the gravitational lensing of the CMB by large-scale cosmic structure.

This thesis describes the Simons Array design as well as several developments that have enabled its sensitivity and their implementation in the experiment. After a brief overview of the scientific motivations and measurement strategies of CMB polarization imaging surveys, an overview of the design and construction of the Simons Array instruments is given. The development of optimized packaging and assembly of close-packed detector hardware and developments in the cryomechanical support of large cryogenic detector arrays are then described. Additionally, advances in the frequency division multiplexed readout of CMB detector arrays representing a factor of several increase in multiplexing capability are presented. Finally, the integration and field commissioning of the first Simons Array telescope is described, and a summary of its initial performance during observations is given.