Nim: `Unable to process type: nnkBracketExpr` when unmarshal to type with Table[string, seq[string]]

Question

The following type Response:

type
  Response* = object
    name: string
    vers: string
    features: Table[string, seq[string]]

which I'm trying to unmarshal a json to:

  let json = parseJson(text)
  let test = to(json, Response)

However to(json, Response) is throwing the following exception:

Error: unhandled exception: false Unable to process type: nnkBracketExpr

Can't figure out what I'm doing wrong, do I need to specify the features Table in another way?

Thanks