So, I've added Cauldron.Interceptors.Fody 3.2.3 and Fody 4.2.1 (I'm still using MSBuild 15) to my project via Nuget.
My FodyWeavers.xml file looks like:
<?xml version="1.0" encoding="utf-8"?>
<Weavers>
<Cauldron.Interception />
</Weavers>
However, when I try to build, I get the following error:
Fody: No weavers found for the configuration entries Cauldron.Interception. Add the desired weavers via their nuget package.