I've been using the smartbit api to derive the next receiving address for a while now. However it only works for Legacy addresses and not Segwit addresses. I now have a Ledger Nano s and need a similar api to obtain the next address in my HD wallet without having to open Ledger Live. Is there such a service? If not, how can I calculate a series of addresses using the xpub / ypub only. (Javascript if possible)