Since the behaviour of CRNs is asynchronous, a fact evident through their equivalence with Petri net models (Cook et al. 2009), the main difficulty with programming them is the need to control the order of reactions. In Cook et al. (2009) it is suggested that this “uncontrollability” can be handled by changing rate constants, an idea followed up in Napp and Adams (2013), where CRN designs for basic arithmetic are given based on two rate constants, “fast” and “slow”. Our designs, on the other hand, exploit the asynchrony of the underlying CRN model and work with uniform rates.