Audience asks whether reusable test-only objects (fake dice, fake current-time) should live with production files so they can be shared across tests. Rodzik never keeps them with production code — he would rather duplicate a rarely-changing fake than risk test code leaking into production. Suggests helpers or factories if deduplication is needed. A follow-up audience comment recommends running the same behavior suite against both real and fake implementations (an approach covered in 99 Bottles and POODR by Sandi Metz), ideally with the team that owns the real class also owning the fake. Another attendee suggests RBS to keep signatures aligned automatically.