Spotify is a moving target, however. It may change its API, remove it completely, etc. I think you can only be truly done if you don’t rely on a third party.

> I think you can only be truly done if you don’t rely on a third party.

On a third-party that changes. Making software for a specific hardware like a game console or a specific e-reader may still technically rely on a third-party but doesn’t carry the same risk and you can definitely say you’re done.