In this line the types are defined as a Record<string,number> (pretty much); but from what it seems, all the properties there should be named.
Will this be done? Does it need to be done? That would be the only way to get both types, and auto-completion so it's quite useful.
According to this SO answer. the typeRoots isn't a good way to add the types.
Unsure whether you disagree, since you have it as recommended in the README.md