I was thinking about something similar the other day when I was setting up a language server in my IDE for a non-mainstream programming language.

What if there was a language we could develop APIs / libraries with that would automatically work with any other language / runtime? I guess I'm describing C interop, but that's too low level. C stands on it's own. I have no idea how to solve this but there would have to be some standard interface that the C interopt is developed against to provide additional context / metadata to allow more native interoperability.

I don't know if I'm doing a good job explaining it. But, the idea is just like a language server. A server is implemented by a specific runtime and it can automatically interop with any client-library written in any other language, natively. This just sounds like wishful thinking.