Deprecated API versions keep answering

You shipped v3 of your API in March. Forty customers are still on v1. Every quarter someone proposes the sunset email, not because v1 is broken but because v1's deployment is a line item and someone has to defend it.

On Hoody, v1 is a container. So is v2. So is v3. Three aliases, three containers, one bare metal box. v1 gets a few thousand requests a day and otherwise sits idle, sharing most of its disk blocks with the others copy-on-write. It costs the box nothing measurable to keep answering.

So you stop sunsetting versions on a cost schedule. You sunset them when the last customer leaves, or never. The integration a customer built in 2023 keeps working in 2028, and they notice that about you.

On per-app pricing, backward compatibility is a cost; on a flat-rate box, it's a default.