Build Product
Use the product's current identity, storage, job, and event providers. Do not invent a second live writer or hide required durability in process memory. Prove the real user path, not only configuration. A green check that never exercised the user path is not the slice.
Open event contracts when the slice creates, publishes, consumes, delivers, or observes something called an event.
Use prototype-product when the direction is still a probe. Use maintain-product for a live defect. Use finish-product to deepen an already integrated promise.