Release announcement is at https://dantti.wordpress.com/2020/02/17/cutelyst-2-10-0-and-simplemail-v2-released/ It just says "many important bugfixes", though. No details. While here, I've enabled two plugins in cutelyst, CSRF protection and static compression support. This isn't at the BUILD_ALL level, but should make cutelyst more useful in its default package state.