Polymers such as DNA, RNA and polypeptides are essential for information storage, replication, and catalysis, and fundamental to life as we know it. We can assume that earlier, or other, forms of life also require some form of polymers to perform these vital functions. Two of several unknowns in prebiotic chemistry are how 1) information-storing polymers can develop through abiotic chemical processes, and 2) under which chemical conditions (i.e., where in the Universe) such processes may occur. The first biomolecular building blocks may have originated through chemical processes native to the early Earth, or they may have been exogenously delivered, e.g., via asteroids and comets. Both scenarios imply that precursor molecules or polymers are subsequently able to transform into biologically relevant structures. In this work, we use quantum chemistry to map the thermodynamics of one such family of proposed precursors: hydrogen cyanide (HCN) and HCN-derived molecules and polymers.