So I have an existing typescript project, can I still use your software to build the app part of it in a monorepo?

We don't currently have support for editing code directly within a repository, but that's something we're excited about adding.

In the meantime, one thing that's worked well for us is building a component/screen/etc as a standalone piece in bitrig, and then bringing it into a larger project from your computer later. You can easily export the code you make in bitrig for those kinds of workflows.