[wpollock]

> Programming languages used for correct-by-design software (Ada, C++, Rust) ...

A shoutout to Eiffel, the first "modern" (circa 1985) language to incorporate Design by Contract. Well done Bertrand Meyer!

[pjmlp]

With people still paying to get the compiler, https://www.eiffel.com

[wpollock]

eiffel.com is a support tooling company. Eiffel the language has the website <https://www.eiffel.org/>. Both sites are worth a look.