fhirclient

I'm trying to utilize smart on fhir's fhirclient in my nativescript app, but after I install fhirclient using:
npm i fhirclient

I'm getting the following error:
ERROR in node_modules/fhirclient/index.d.ts(4,21): error TS2503: Cannot find namespace 'fhirclient'.

I get this same error if I use nativescript-nodeify or not. Please help! I'm sure it's something easy I'm missing, as I'm still a newbie.