We've been storing values on errors using https://github.com/levenlabs/errctx https://github.com/levenlabs/errctx for close to a decade now. We have a separate

We've been storing values on errors using https://github.com/levenlabs/errctx https://github.com/levenlabs/errctx for close to a decade now. We have a separate logging library that stores a KV map but technically you can store anything on errors. I recently just made it unwrap errors to find deeply stored keys.