So while the ideas discussed are interesting, the origins are a bit off.

Flow typing, is actually called Flow-sensitive typing.

Contracts were introduced into the industry via Eiffel, which continues to be sold via Eiffel Software company.

By the way, at the recent DConf 2026, during the panel discussion, contracts was actually one of the features that were discussed as something that they would remove from the language, if doing it all over again.

Rust's borrow checker, is based on Affine Types, and the first systems language that looked into it was Cyclone, which AT&T started as research project in colaboration with an university, to eventually replace C.