How many Claude Codes do you run in parallel?

A couple weeks ago, Boris Cherny (the creator of Claude Code) shared a bunch of really useful tips on getting the most out of Claude Code. #1 at the top of the list: do more in parallel. He himself runs 10-15 Claude codes in parallel.

His advice and practice makes sense: coding agents give us the ability scale infinitely. At this point, the only real limiter is our own ability to manage all of these agents.

How many Claude Codes do you run in parallel? And what are your tips for setting things up to maximize this?