Ionic Angular monorepos with NX

I’m having an immediate problem with the steps in this article. I get as far as creating the Generating Applications section but when I run with: nx serve my-app I get this:

TypeError: _b.flat is not a function

Any clue what’s wrong? I am currently using ionic outside of an nx workspace with no problems at all.

Ionic:

Ionic CLI : 6.11.6

Utility:

cordova-res (update available: 0.15.3) : 0.14.0
native-run : 1.3.0

System:

NodeJS : v10.16.1
npm : 6.9.0
OS : macOS Catalina

UPDATE: apparently something in here doesn’t work on Node 10. Updated to 12.16.3 and it works correctly.