That is not possible. You get no usage data if someone uses your open source library, and the maintainer of the library that depends on you could be dead. Thi

That is not possible. You get no usage data if someone uses your open source library, and the maintainer of the library that depends on you could be dead. This is a fine approach when you mail your API users an invoice every month, just tack on "hey start using v2". But open source libraries don't have that invoice cycle. The most you can do is tack on a warning in a future patch version, but they would have to update to that first.