[eesmith]

> "One thing we thought of was to replace those tests with contributions (or bug/issue fixes) to a company's open-source project."

That sounds like you are saying that job applicants need to do unpaid work which economically benefits the company before being hired.

Do they need to sign a CLA as well, or do they at least get to keep ownership of the copyright?

More specifically, if I contribute something under the AGPL to an otherwise MIT-licensed project, will that count against me?

If the point is to see if my skill set is relevant, then that shouldn't matter, right? Because you can still evaluate it, hire me, and have me redo the work under a standard employee work-for-hire arrangement.