CRNs can also be viewed as computing functions over reals or Booleans. A single CRN computes a function over a finite domain, which is analogous to Boolean circuits in the sense that any given circuit computes only on inputs of a particular size (Soloveichik et al. 2008). An implementation of dual-rail logic gates that are rate-independent is given in Chen et al. (2014). In contrast, our designs are composable and capable of performing non-trivial computation.