`map[string]interface{}` is just a map with string keys and `any` as a value, and is commonly used as the type for a JSON object. Unless you have a completely specified type for your JSON object (at that point might as well use a `struct` with all of the fields defined), the best you _could_ do would be something like a recursive type `type JSON = bool | string | []JSON | map[string]JSON` in some hypothetical version of Golang with recursive types and unions.

Also, if you're making a set, use `map[string]struct{}` instead of `map[string]interface{}` as `struct{}` takes 0 bytes whereas `interface{}` takes 8.