Probably not a big thing.. but just let you know that
Line 7 in (https://github.com/geocortex/vertigis-web-samples/tree/master/samples/commands-and-operations/src)/index.ts
getService: () => new CustomService()
there is no config as parameter which is correct
however, in tutorial of developer center the code is: getService: (config) => new CustomService(config) which is not right
Couple of inconsistencies have been noted between github and tutorial