Function serve 

pub fn serve<C, L>(language: L) -> Result<(), Box<dyn Error + Send + Sync>>
where
    C: Clone + PartialEq + Send + 'static,
    L: Language<C>,

Runs a language server on stdio until the client sends shutdown + exit.

This is the whole integration point:

fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
    increparse_lsp::serve(MyLang { engine: build_engine() })
}