Sharing types between the main application and functions

Once interfaces ( or other entities ) have been defined inside the main application /src/** and imported from within /functions --> import { InterfaceTest } from '../../src/app/path';, where the path resolves to a file within a sibling of /functions, the folder structure of compiled output generated by tsc in the /functions folder changes to reflect the "touched" structure of the imports from /src/app.

Is there a method i'm missing for using types within both projects? Aside from adding more build steps or a type file.