rem usage breaks styles in RN 62 w TypeScript

Hello - not sure if I'm doing something wrong or if the issue is TypeScript but when I try to use rem in EStyleSheet.create the view using the style will not render and nothing after it will render either. When I change to 34 instead of '34rem' it will render properly.

const styles = EStyleSheet.create({
  title: {
    fontSize: '34rem',
    color: Colors.white,
  },

I'm also trying to use EStyleSheet.build in App.tsx to set a global $rem def but this doesn't seem to fix the issue.

const rem = width / (Platform.OS === 'ios' ? 375 : 0.95)

EStyleSheet.build({
  $rem: rem,
  $backgroundColor: Colors.primaryBlueColor,
})

Any ideas if this is typescript related? I have it working in a different project that's not using TS...

Environment

Android device
VSCode
package.json: "react": "16.11.0", "react-native": "0.62.2", "react-native-extended-stylesheet": "^0.12.0",

vitalets / react-native-extended-stylesheet

rem usage breaks styles in RN 62 w TypeScript #138