[yazaddaruvala]

> trying to figure out how to write generic traits using higher ranked trait bounds with understanding variance sufficiently

I agree! You’re currently dealing with writing non-ergonomic Rust.

I’d argue your domain is missing a fundamental reusable library/framework or the framework is currently missing a piece. Once someone publishes the needed library (hopefully it’ll be you) then everyone consuming it can just Lego block multiple crates together. Lego blocking crates together (barring heavy macro crates) is very ergonomic.

95% of all new code written is Lego blocking other crates. 5% of new code written is to build new or improve/patch crates.