Although based on the well-tested and officially-maintained Ractive-Backbone adapters, there are some important differences in this implementation that warrant dedicated unit tests.
I merged the adapters into a single npm module, wrote tests, and donated it to the Ractive.js team. This project now includes that code via npm (see commit a3541a0f6a47956841273333e448a4c008f5ac06).
Although based on the well-tested and officially-maintained Ractive-Backbone adapters, there are some important differences in this implementation that warrant dedicated unit tests.