Keep in mind that one can create most if not all of the bower.json file by using spago bump-version. You might need to do some editing after that, but it’ll get you 80-100% there. After that, you can run pulp publish as normal.
Note: this is not directed at Harry, but more at the general audience of those who are reading through this thread, assuming they are wondering how they can still use spago to publish their library to Pursuit.